WATER RESOURCES PLAN
SCOTT COUNTY
MAY 2006
AMENDED OCTOBER 2007
AMENDMENT APPROVED
AUGUST 2008
Table of Contents
Executive Summary/Acronym List................................................................... Pages i - ii
Introduction ......................................................................................................Pages 1-7
Section 1 Land and Water Resource Inventory.............................................Pages 8-40
Section 2 Impacts on Other Units of Government .......................................Pages 41-49
Section 3 Background and Assessment of Issues ......................................Pages 50-85
Section 4 Goals and Policies.....................................................................Pages 86-123
Section 5 Administration..........................................................................Pages 124-132
Appendix A – Glossary
Appendix B – Scott County Proposed Work Plan
Appendix C – Vermillion River Watershed Supplementation Information
Vermillion River Watershed Joint Powers Organization Goals, Policies and
Standards, and the Scott County Water Resources Plan
Executive Summary
Page i
EXECUTIVE SUMMARY
The purpose of the Scott County Water Resources Plan (Water Plan) is to serve as the basis for
managing surface and groundwater within the unincorporated areas of Scott County. Scott
County is responsible for completing a Local Water Plan for the unincorporated areas within the
Scott Watershed Management Organization (WMO), the Lower Minnesota River Watershed
District (LMRWD), the Prior Lake – Spring Lake Watershed District (PLSLWD), and the
Vermillion River Watershed Joint Powers Organization (VRWJPO). This Water Resources Plan
will serve as the County’s Local Water Plan upon approval by the respective Watershed
Organizations and adoption by the Scott County Board of Commissioners. This Water Plan has
been completed in accordance with MN Statute 103B.235, MN Rules Chapter 8410, and the
various Watershed Organization Comprehensive Water Resource Management Plans.
The statute and rule listed in the above paragraph were used to formulate a set of overall water
resource management goals for Scott County. These overall goals are provided below, with more
specific management objectives provided later within this document.
1. To manage the quantity and to improve the quality of runoff entering rivers, streams,
lakes, wetlands, and groundwater within the Scott County.
2. To protect and enhance wetland ecosystems by managing contributing watersheds,
and to ensure/encourage a measurable net gain of wetland functions and acreage
throughout Scott County.
3. To preserve and enhance surface water quality in Scott County’s water bodies and
watersheds, commensurate with the eco-region and desired uses.
4. To protect groundwater quality and improve groundwater supplies through the
effective implementation of this Water Resources Plan and the Scott County
Groundwater Protection Plan, which is incorporated by reference into this Plan.
5. To reduce, to the greatest extent possible, non-point source pollution from
agricultural activities, development, and other land disturbing activities.
6. To protect human life, property, and surface water systems that could be damaged by
flood events.
7. To implement the County’s current Comprehensive Plan as a guide for development
within the County by providing policies, objectives, and ordinances to support
Scott County Water Resources Plan –Amendment 1
October 2007
Executive Summary
Page ii
development while at the same time protect and manage the County’s water
resources
8. To inform, educate and involve individuals, groups, businesses, industry and
government in the protection and cleanup of Scott County’s water resources, thereby
increasing the understanding of water resource management and creating a long-term
commitment to improve and protect the County’s water resources.
This Water Plan incorporates the majority of the Scott WMO’s Comprehensive Water Resource
Management Plan, both in style and content, as most of the unincorporated areas of the County
fall within the WMO’s jurisdiction. Therefore, the County is adopting similar goals, policies, and
objectives to address the water management issues that affect the unincorporated areas of the
County, as identified by the WMO. However, this plan does acknowledge that the County must
recognize and administer ordinances that address the standards and rules that other watersheds
administer in their jurisdictions where they affect the unincorporated areas of the County. Scott
County will actively work with the Lower Minnesota River Watershed District, the Prior Lake –
Spring Lake Watershed District, and the Vermillion River Watershed Joint Powers Organization
to ensure compliance with their respective standards and rules under the Scott County Water
Resources Plan.
This plan does not purport to identify all water resource management issues the County may face.
The plan is proposed to be a dynamic document which will undergo future updates as other water
resource management issues are identified as a result of continued land use and cultural changes
in a rapidly developing County.
Scott County Water Resources Plan –Amendment 1
October 2007
Introduction
Page 1
INTRODUCTION
I.
Plan Purpose
The Scott County Water Resources Plan (Water Plan) fulfills the requirements of MN
Statute 103B.235 – Local water management plans, MN Rules Chapter 8410, and the
Scott WMO Comprehensive Water Resource Management Plan. The overall purpose of
this Plan is to protect, preserve and manage surface and groundwater systems within the
unincorporated areas of Scott County in the face of rapid urban growth and intensive
agricultural activity.
The Plan also presents sustainable and equitable means to
effectively reach this purpose by providing guidance and specific standards for decisionmakers, residents, landowners, educators, and implementing staff at the local level.
II.
Regulated Areas
The Scott County Water Resources Plan addresses stormwater management strategies for
the unincorporated areas of the County.
This includes the following eleven (11)
townships; Belle Plaine, Blakeley, Cedar Lake, Credit River, Jackson, Helena, Louisville,
New Market, St. Lawrence, Sand Creek, and Spring Lake.
III.
Compatibility with Other Jurisdictions
This Water Plan has been completed to meet the minimum requirements of the Scott
WMO Comprehensive Water Resource Management Plan adopted in February 2004.
Portions of unincorporated Scott County fall within the jurisdictional boundaries of three
other watersheds; Lower Minnesota River Watershed District (LMRWD), Prior LakeSpring Lake Watershed District (PLSLWD), and the Vermillion River Watershed Joint
Powers Organization (VRWJPO).
It is important that the County’s Water Plan be
coordinated with the standards and rules of these three watershed jurisdictions as well as
the Scott WMO.
The Scott WMO attempted to maintain consistency with these
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
Page 2
watershed jurisdictions when the WMO drafted and adopted their Comprehensive Water
Resource Management Plan. Therefore, by meeting the minimum requirements of the
Scott WMO, the County feels that this Water Plan will be consistent with the
management goals of the other watershed districts. However, the other watersheds may
have different standards and rules to meet these common goals. Therefore, the County
will revise the existing Zoning Ordinance so that land development/alterations in areas
outside of the Scott WMO will have to meet the rules of the other watersheds where more
stringent rules would apply.
For example, if a parcel of land is developed within the VRWJPO and the VRWJPO
establishes larger buffer widths than the minimum requirements of the Scott WMO, the
developer will be required to meet the requirements of the VRWJPO.
The County is also working with the PLSLWD to administer permitting of water resource
management for the unincorporated areas of the County that fall within the watershed
district. Therefore, the PLSLWD would not need to issue a separate permit for land
disturbing activities that also receive a grading permit from the County. The County
would be responsible for ensuring that an applicant not only meet the regulations of the
County, but also the minimum requirements of the watershed district.
This Water Resources Plan has been reviewed and approved by the PLSLWD and the
Scott WMO, and reviewed by the LMRWD as of the date of this amendment (October
2007). This amendment is being completed primarily to demonstrate equivalency with
the VRWJPO Plan and Standards. There are minor changes in the Executive Summary,
the Introduction and Sections 2, 4 and 5 of this plan. However, the primary amendments
are incorporated with the addition of a new appendix to the plan.
This appendix
(Appendix C) is specific to the VRWJPO requirements and benchmarks the Scott County
Water Resources Plan components with the requirements of the VRWJPO Watershed
Plan.
Where gaps are identified actions by the County are detailed or equivalent
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
Page 3
approaches described. This appendix is an extension of the plan specific to the resources,
goals, policies, and actions of the County as they apply to areas in the Vermillion River
Watershed.
IV.
Management Goals, Objectives and Policies
Scott County adopts the Management Goals of the Scott WMO through the adoption of
this Water Plan. The Scott WMO followed the guidelines established in State Statute to
develop a set of overall water management goals, which are listed in the Executive
Summary and Section 4 of this Water Plan. These goals provide recognition of the
County’s and WMO’s water resources and guidance for managing those resources.
Based on these goals, this Plan identifies those priority issues that require appropriate
action.
The Scott WMO planning process included reviewing the existing first generation
watershed plans, citizen and landowner surveys, focus groups, and several issue
identification and prioritization sessions with the Citizen Advisory Committee (CAC) and
Technical Advisory Committee (TAC) to identify and prioritize issues. High priority
issues identified by the Groundwater Advisory Committee in 1999 were also included.
As a result of this process during 1999 through 2001, issues requiring action were
identified. The County’s Water Plan identifies policies and implementation objectives
for each of these issues, as summarized below:
A.
Stormwater Management Objectives
1. Establish, evaluate, refine, and implement stormwater management, erosion
control, and wetland protection rules and ordinances for land disturbing
activities, including National Pollutant Discharge Elimination System
(NPDES) Phase II.
2. Establish stormwater management system maintenance standards and identify
public management responsibilities.
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
Page 4
3. Encourage restoration on damaged/susceptible stream banks/corridors for
erosion control.
4. Develop stormwater management plans that identify capital and operational
costs for and methods to address fees to new development for stormwater
management.
5. Develop
a
regional
stormwater
management
strategy
using
hydrologic/hydraulic modeling.
6. Mitigate and reduce the impact of localized flooding when feasible.
7. Mitigate and reduce the impact of stormwater discharge on downstream
conveyance systems.
B.
Wetland Management Objectives
A County-wide Level III wetland inventory has been completed by the Scott Soil
& Water Conservation District (SWCD). This data can be viewed as a layer on
the County’s GIS program. The following objectives also need to be met.
1. Develop and implement a Comprehensive Wetland Management Plan, to
include a wetland protection program.
2. Establish wetland buffer requirements for structures, land disturbing activities,
and adjacent uses in new developments based on wetland function levels.
C.
Surface Water Quality Objectives
1. Support the WMO’s objective to develop and implement water quality
monitoring and diagnostic programs to preserve, protect and improve the
water quality of the County’s surface waters.
2. Support the WMO’s objective to analyze monitored data, identify trends,
identify data gaps, and target areas with water quality issues.
3. Support the WMO’s objective to establish implementation programs through
the establishment of water quality goals and the evaluation of the
effectiveness of management activities on the affected water bodies.
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
Page 5
4. Minimize water quality impacts from new development and land disturbing
activities by requiring the use of best management practices and by providing
rules and ordinances to implement erosion/sedimentation control practices.
5. Maintain active involvement with the NPDES Phase II program.
D.
Groundwater Objectives
1. Implement the strategies and objectives of the Scott County Groundwater
Protection Plan.
2. Provide
education
on
the
hydrologic
cycle,
groundwater
and
groundwater/surface water interactions.
E.
Agricultural Uses Objectives
1. Reduce soil erosion (sheet and rill, wind erosion, gully and streambank
erosion) on agricultural land to the recommended "T" value (the maximum
rate of soil erosion that will maintain a high level of long-term crop
production) or below.
2. Protect to the greatest extent possible all surface and groundwater resources
from agricultural soil erosion, sedimentation, nutrient and chemical
contamination.
3. Preserve and protect all agricultural wetland areas to improve water quality,
prevent flooding and erosion from surface flows, protect fish and wildlife
habitat and promote groundwater recharge.
4. Protect to the greatest possible extent all existing wildlife habitat areas and
promote the development of additional wildlife habitat on agricultural lands.
F.
Flooding Objectives
1. Manage runoff from development/redevelopment through stormwater rate and
volume control techniques and optimize site design practices to alleviate
downstream flooding.
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
Page 6
2. Cooperate with Minnesota Department of Natural Resources (MnDNR) to
ensure that water body control structures and outlets are in good working
condition and that they remain in good working condition within shoreland
areas and public water bodies.
3. Limit floodplain alterations in order to obtain “no net loss” of floodplains;
including the preservation, restoration and management of floodplain
wetlands.
4. Mitigate or reduce the impact of localized flooding when feasible and ensure
that structures are properly located relative to the floodplain.
5. Work with the Federal Emergency Management Agency (FEMA) to complete
floodplain mapping under their Cooperating Technical Partners (CTP)
program.
G.
Urban Development Objective
1. Coordinate the implementation of the Scott County Water Resources
Management Plan with the implementation of the current Scott County
Comprehensive Plan Update.
H.
Education Objective
1. Implement the Education Strategy activities.
V.
Plan Overview
The Plan is comprised of five main sections including a section containing pertinent
definitions and acronyms, and several appendices. The main sections are briefly outlined
below.
A.
Section 1: Land and Water Resource Inventory
This section summarizes information and presents data sources characterizing
Scott County’s land and water resources. Important points include:
•
Glacial deposits cover bedrock geology throughout the county.
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
•
Page 7
Groundwater aquifers are highly susceptible to contamination along the
Minnesota River valley.
•
Prior to Euro-American settlement circa (1850) the majority of Scott County
was forested, but today the county is urban and agricultural. Continued rapid
urbanization will place more pressure on Scott County resources.
•
Scott County provides numerous recreational opportunities, with the
Minnesota River, lakes, parks and historic/cultural sites, in addition to
providing habitat for rare and endangered species.
B.
Section 2: Impacts on Other Units of Government
This section characterizes the role of the Scott County Natural Resources
Department and Community Development Division, County administrative tasks,
and intergovernmental and institutional relationships.
C.
Section 3: Assessment of Issues
This section discusses the concerns related to water resources in Scott County.
Key issues include:
•
Lakes and streams with water management concerns.
•
Stormwater rate and volume control and impacts of discharges.
•
Soil erosion in urban, rural, and agricultural areas.
•
Impacts on groundwater from feedlots, landfills, mining operations, and other
land disturbing activities.
•
Coordination/communication between the County, cities, townships, and the
County’s Public Works Division.
D.
Section 4: Goals and Policies
Section 4 outlines specific policies, objectives, and implementation activities for
the main issue areas, including stormwater management, wetland management,
surface water quality, ground water, agricultural uses, flooding, urban
Scott County Water Resources Plan – Amendment 1
October 2007
Introduction
Page 8
development and education. The section also includes implementation action
tables with specific priorities, projects, participants, timelines, and costs.
E.
Section 5: Administration
This section outlines the organization of the Scott County and the Community
Development Division, along with its responsibilities, development review
process and administration, funding mechanisms, and Plan adoption and
implementation procedures.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 8
Section 1
Land and Water Resource Inventory
I.
Introduction
Scott County was established and organized by an Act of the state legislature on March 5, 1853.
The County, with an area of 375 square miles, is comprised of 11 townships and eight cities.
The County was the fastest growing county in Minnesota during the decade of the 1990s.
During that period the County’s population grew almost 55 percent from 57,846 persons in 1990
to 89,498 in the 2000 Census. Scott County has the 9th largest population out of the 87 counties
in Minnesota and was named the 8th fastest growing county in the U.S in 2003. A detailed
discussion of the Scott County history and population trends can be found in the Scott County
2020 Comprehensive Plan Update and on the County’s web site at www.co.scott.mn.us.
The majority of Scott County falls within the jurisdiction of the Scott WMO which is comprised
of portions of five watersheds: Sand Creek, Southwest, Shakopee Basin, Credit River and Prior
Lake Spring Lake (Map 1). The remainder of the unincorporated areas of the County is within
one of three other watershed jurisdictions: the Lower Minnesota River Watershed District, the
Prior Lake Spring Lake Watershed District, or the Scott County portion of the Vermillion River
Watershed District Joint Powers Organization (Map 2). The maps referred to within the text of
this document can all be found at the end of Section 1. Appendix C contains additional maps
showing greater detail for the Vermillion River watershed portion of the County.
Prior to settlement by Euro-American pioneers, Scott County had large areas of hardwood forests
with some pockets of prairie land (Map 3). Today most of that land has been cleared for
farming and human settlement. Land use and land cover across Scott County is diverse and
ranges from urbanized areas to agricultural operations.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
II.
Section 1, Page 9
Climate and Precipitation
The hydrologic cycle describes the movement of water through the environment. Beginning
with precipitation as the first of four major phases of the hydrologic cycle, the other phases are
infiltration, evaporation, and transpiration. Records of precipitation will be essential or useful as
supplements to specific investigations of water resources.
Various hydrologic and hydraulic design models require different climatic information.
Depending on the model used, the climatic variables needed include rainfall amount, annual
average precipitation, temperature, precipitation frequency, and snowmelt. This section provides
information that is basic to most hydrologic and hydraulic design models, as well as information
that may be useful in responding to questions about rainfall and runoff.
Monthly precipitation records from the Minneapolis/St. Paul International Airport weather
station from 1940 to 2000 are shown in Table 1.1. This station is located about 10 miles
northeast of the County. The Minneapolis/St. Paul records were chosen because this station has
the longest continuous record for the region. As indicated in this table, the long term average
annual precipitation is 27.8 inches per year. Of this, 85 percent falls between March and
October, and 15 percent falls between November and February, mostly in the form of snow.
Most rainfall occurs in June. Average snowfall in this area is approximately 49.6 inches per year
(http://climate.umn.edu.) The State Climatologist’s office also maintains volunteer precipitation
records for most of Minnesota. Volunteer observations for Scott County for years 1980 through
2000 are summarized in Figure 1.1.
TABLE 1.1 Minneapolis/St. Paul Monthly Precipitation Summary, 1940-2000
Year
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
Jan
0.37
0.74
0.15
0.91
0.24
0.63
0.94
0.71
0.15
1.65
1.27
0.44
Feb
0.91
0.89
0.45
0.57
1.10
1.84
1.15
0.20
1.37
0.14
0.68
1.71
Mar
2.16
0.77
1.74
0.81
1.20
1.95
1.20
0.47
1.43
3.37
2.20
3.00
Apr
1.21
1.87
3.41
0.98
2.24
2.95
0.66
2.44
1.77
1.89
4.39
4.86
May
1.64
2.91
6.78
4.27
6.15
3.09
3.04
2.57
0.74
0.90
2.87
4.14
Jun
7.10
3.29
2.69
4.23
6.69
5.57
7.80
5.30
2.58
2.74
1.26
5.50
Jul
2.46
1.98
3.80
3.78
4.39
4.13
2.76
0.96
1.34
6.01
3.74
5.44
Aug
4.54
3.66
2.11
1.75
3.65
2.27
0.43
2.41
3.37
2.64
1.84
1.94
Scott County Water Resources Plan – Amendment 1
Sep
0.41
3.47
7.53
2.47
0.97
2.13
6.58
1.48
1.04
2.67
1.46
5.80
Oct
1.57
5.52
0.78
1.30
0.26
0.30
2.51
1.10
0.60
1.72
1.22
1.44
Nov
5.15
1.05
0.27
1.64
2.10
0.93
1.22
2.85
1.89
0.42
0.89
2.12
Dec
1.02
0.85
0.85
0.00
0.09
1.41
0.68
0.60
0.67
0.99
1.99
1.21
Total
28.54
27.00
30.56
22.71
29.08
27.20
28.97
21.09
16.95
25.14
23.81
37.60
Avg./year
2.38
2.25
2.55
1.89
2.42
2.27
2.41
1.76
1.41
2.10
1.98
3.13
October 2007
Land and Water Resource Inventory
Section 1, Page 10
Year
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
Jan
1.05
0.55
0.25
0.47
0.48
0.32
0.21
0.11
0.68
0.28
0.55
0.46
0.47
0.47
0.95
3.63
0.71
2.05
0.47
1.22
0.84
0.92
0.17
2.82
0.87
0.65
0.38
1.09
0.94
0.30
2.45
0.67
0.88
0.87
0.90
0.63
1.37
0.52
0.10
0.49
0.66
1.25
1.17
0.36
1.87
1.71
1.64
2.67
0.90
Feb
1.20
1.23
0.32
1.54
0.20
0.83
0.24
0.61
0.22
0.89
2.07
0.41
0.06
1.59
1.55
1.59
0.13
0.31
0.16
1.74
0.49
0.84
1.06
0.79
0.59
0.93
0.24
1.39
0.67
2.14
0.43
1.19
1.64
0.50
0.84
0.13
0.30
1.04
0.77
1.03
0.57
0.39
0.78
0.25
0.24
0.30
0.80
0.40
1.08
Mar
3.09
1.51
2.10
0.52
1.62
1.31
0.32
0.59
0.81
2.81
1.87
1.18
1.35
4.75
2.48
0.96
1.89
0.90
2.05
1.21
1.25
1.12
1.00
1.67
2.83
2.66
0.79
2.55
1.12
0.71
2.09
3.22
1.47
4.48
2.03
0.64
1.33
2.19
3.66
2.29
1.56
1.25
0.32
2.11
1.39
1.18
4.56
1.86
1.12
Apr
0.59
3.55
5.63
1.44
0.67
2.54
2.31
1.23
2.04
5.20
3.18
3.25
2.98
3.52
0.89
4.07
2.94
1.55
3.55
1.11
1.69
2.32
2.42
5.40
0.80
1.84
3.63
0.66
0.83
2.17
1.62
3.97
3.86
1.81
5.88
0.16
1.58
2.66
3.80
3.58
1.99
1.99
3.77
1.90
0.76
1.01
1.56
3.43
1.12
May
2.86
1.92
2.54
0.69
1.96
3.13
1.39
5.03
3.19
3.48
8.03
5.06
3.44
7.86
1.46
0.61
3.74
1.98
4.77
3.14
2.18
2.48
2.08
3.81
1.13
2.86
3.79
4.55
2.29
2.18
4.99
6.20
2.29
3.65
3.48
1.88
1.70
3.38
3.36
6.35
1.15
4.02
2.21
2.43
2.37
1.70
4.40
6.56
4.56
Jun
3.98
7.10
4.71
1.53
6.58
4.12
2.01
4.07
3.08
1.87
1.48
1.91
2.18
4.01
3.51
7.53
6.78
2.93
1.27
3.52
3.31
1.06
5.21
7.99
3.86
3.57
7.09
4.78
5.52
4.42
1.44
5.22
7.95
2.18
5.34
1.95
0.22
3.50
9.82
2.57
3.68
6.28
3.09
3.38
4.76
3.70
6.52
3.68
4.55
Jul
4.56
6.81
1.33
7.10
5.18
6.31
3.15
2.60
1.93
2.94
5.12
1.53
2.02
4.69
2.47
1.36
6.46
2.95
3.66
3.94
5.12
2.90
1.14
0.58
2.45
3.72
3.19
2.34
2.30
4.09
0.92
3.07
3.03
2.20
4.11
17.90
1.17
3.50
5.06
2.95
5.21
5.58
4.12
2.72
2.09
12.60
2.63
4.55
6.10
Aug
4.18
2.75
3.08
2.15
5.22
5.75
3.03
6.60
3.99
2.38
3.47
1.55
5.42
4.04
4.40
2.79
0.75
0.99
2.19
1.78
2.48
3.05
2.75
4.92
1.39
9.31
5.77
7.04
3.26
4.73
3.80
3.12
5.15
5.02
4.44
3.67
4.29
2.92
1.71
3.14
4.54
6.50
2.90
4.59
1.43
6.01
5.99
2.64
3.19
Sep
0.42
0.55
3.65
0.99
0.79
1.65
1.09
2.29
3.79
3.01
2.46
3.47
5.21
4.90
1.69
0.63
6.16
0.49
3.19
2.73
1.96
2.08
0.58
1.31
1.42
4.43
2.47
2.20
3.68
1.46
1.50
3.34
2.65
4.37
6.90
1.28
2.79
1.28
1.88
5.43
5.20
2.04
4.74
2.21
1.30
3.19
1.32
2.73
2.15
Oct
0.01
0.15
1.23
2.21
1.95
1.40
1.55
2.43
0.31
3.03
1.69
0.81
0.57
0.90
3.53
1.73
5.62
2.53
4.97
5.68
1.77
1.29
1.69
0.27
0.49
2.34
0.19
3.16
0.66
2.69
3.45
2.61
5.48
3.66
1.77
0.60
0.80
0.53
1.23
2.52
2.11
0.79
4.65
3.68
3.01
2.03
2.19
0.92
1.09
Nov
1.28
1.54
0.61
1.04
1.35
1.56
1.01
0.63
0.87
1.06
0.52
0.52
1.19
1.98
0.39
0.09
0.54
0.65
3.82
2.67
1.11
1.97
0.66
4.80
0.16
1.42
1.84
0.98
0.26
2.16
3.27
4.93
0.31
1.72
0.62
2.07
2.86
1.38
0.65
5.29
1.95
1.57
1.39
0.88
5.08
0.69
1.32
0.77
3.26
Dec
0.45
1.76
0.33
1.26
0.20
0.24
0.21
1.28
0.55
1.60
0.26
0.60
1.08
1.23
1.02
0.45
2.21
2.06
0.43
0.70
1.57
1.10
0.35
0.79
0.51
1.15
0.88
0.33
0.24
0.92
4.27
1.53
2.24
1.20
0.31
1.25
0.67
0.42
1.01
1.05
1.05
0.55
0.53
1.15
1.75
0.31
0.46
0.33
0.93
Total
23.67
29.42
25.78
20.94
26.20
29.16
16.52
27.47
21.46
28.55
30.70
20.75
25.97
39.94
24.34
25.44
37.93
19.39
30.53
29.44
23.77
21.13
19.11
35.15
16.50
34.88
30.26
31.07
21.77
27.97
30.23
39.07
36.95
31.66
36.62
32.16
19.08
23.32
33.05
36.69
29.67
32.21
29.67
25.66
26.05
34.43
33.39
30.54
30.05
Min
Max
Avg
0.10
3.63
0.88
0.06
2.14
0.82
0.32
4.75
1.77
0.16
5.88
2.45
0.61
8.03
3.27
0.22
9.82
4.19
0.58
17.90
3.84
0.43
9.31
3.56
0.41
7.53
2.67
0.01
5.68
1.94
0.09
5.29
1.63
0.00
4.27
0.94
16.50
39.94
27.96
Avg./year
1.97
2.45
2.15
1.75
2.18
2.43
1.38
2.29
1.79
2.38
2.56
1.73
2.16
3.33
2.03
2.12
3.16
1.62
2.54
2.45
1.98
1.76
1.59
2.93
1.38
2.91
2.52
2.59
1.81
2.33
2.52
3.26
3.08
2.64
3.05
2.68
1.59
1.94
2.75
3.06
2.47
2.68
2.47
2.14
2.17
2.87
2.78
2.55
2.51
For current data see:
http://climate.umn.edu
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 11
The factors affecting the fate of
precipitation are complex.
FIGURE 1.1: Monthly Precipitation for Scott County, 1980-2000
10
Local
9
seasonal
precipitation,
variations
temperature,
in
and
vegetation, in addition to cultural
and physical features can affect how
a
watershed
precipitation.
responds
to
8
Precipitation (inches)
and
7
6
5
4
3
The University of
2
Minnesota estimates that 76 percent
1
of precipitation is returned to the
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
Month
atmosphere by evapotranspiration,
Max.
Min.
Mean
22 percent is included as runoff, and
2 percent is recharged into the groundwater. Using these figures, of the 27.8 inches of annual
precipitation in Scott County, approximately 21.1 inches is returned to the atmosphere through
evapotranspiration, 6.1 inches runs off, and 0.6 inches is recharged to the groundwater.
Runoff occurs when soils are sufficiently saturated and surface storage conditions are exceeded.
Volumes of runoff vary according to storm event, storm topography, storm intensity, land cover,
temperature, etc.
High-volume, short-duration, high-intensity storms, in addition to rapid
snowmelt, tend to result in greater runoff than storms of similar magnitude extended over longer
periods. Additionally, greater volumes of runoff occur in areas where most precipitation falls
from late fall to early spring, or areas with many impermeable surfaces. In Scott County, most
runoff occurs as a result of snowmelt combined with rainfall on frozen or saturated soil in the
spring, as well as rainfall on saturated soils in the autumn months of September and October.
Significant rainfall events are usually classified as 1-, 2-, 5-, 10-, 25-, 50- and 100-year, 24-hour
storm events. These terms do not mean that a “100-year” storm event occurs only once every
100 years. Rather, each event has a certain probability of occurring in any given year. For
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 12
example, a 2-year storm event has a 50 percent chance to occur in a given year, a 5-year event
has a 20 percent chance to occur, a 100-year event has a 1 percent chance, and so forth.
Rainfall intensity during a particular period can vary significantly throughout the County, since
storm events in this region are often
extremely localized. It is not unusual to
have 100-year and 2-year storm events
occurring in different parts of the County
at the same time. More often than not,
many
storm
events
of
FIGURE 1.2: Precipitation Events Used in Modeling
24-hour
Event
Rainfall
(inches)
1-year
2.33
2-year
2.78
different
5-year
3.58
probabilities can occur in the County in
10-year
4.20
any given year. Figure 1.2 summarizes
25-year
4.83
50-year
5.35
100-year
6.00
the typical precipitation events used for
hydrologic and hydraulic design within
Scott County.
The typical growing season in Scott County is about 139 days. The average date of the first
killing frost is September 29 and the average date of the last killing frost is May 13 (USDA
1959). The average temperature in the County is about 45° F.
Additional information or updated information can be accessed at the “Climatology Working
Group” homepage, run by the Minnesota Department of Natural Resources, University of
Minnesota Extension Service and the University of Minnesota, at: http://climate.umn.edu .
III.
Geology and Topography
Portions of this section were taken from the “Scott County, Minnesota Groundwater Protection
Plan”, adopted March 23, 1999 by the Scott County Board of Commissioners. Please see the
Groundwater Plan for additional information. In addition, the Geologic Atlas for the County was
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 13
updated in 2006. The following discussion does not include this more recent information. The
new information is available from the County and the University of Minnesota.
The groundwater we use is contained in the rocks, soils, and minerals of our area. That is, the
geology of the County forms the entry points, exit points and pathways of water in the
groundwater system. The purpose of this section is to convey a general understanding of Scott
County geology.
Like other counties of the metropolitan area, Scott County has three basic geologic units, which
are as follows from top to bottom:
FIGURE 1.3: General Scott County Geology
1.
Glacial deposits.
2.
Bedrock formed in shallow marine
sediments deposited between 480 million
and 950 million years ago.
3.
Bedrock of volcanic of metamorphic
origin.
Figure 1.3 shows the geologic layers underlying
Scott County.
The origin of the geologic
material, how it was deposited, and how it was
subsequently re-worked determine the properties
of these three geologic units.
The material
within the three units may be thought of as water
bearing (porous and permeable enough to
contain
and
transmit
water
in
pumpable
quantities) or as confining (not permeable
enough). Porosity can occur as fractures in solid
material, as sand and gravel deposits, or as a
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 14
combination of the two.
The combined characteristics of the water-bearing and confining geologic materials determine
the location and flow of groundwater aquifers. Groundwater flow may be thought of as having a
vertical component and a horizontal component.
Vertical water movement characteristics are determined by the flow pathways available to water
in the geologic structure, as well as the time necessary for water to move downward to a zone of
saturation.
Geological structure also defines the horizontal movement of groundwater and the size of the
groundwater units. The rate of horizontal movement reflects the rate of potential contaminant
spread in an aquifer system once the contaminant has found its way to the aquifer.
The re-working of geologic material over time creates factors important to infiltration and
recharge, affecting groundwater vulnerability. For example: today’s topography and drainage
network are the result of long-acting forces that have produced features such as lakes, wetlands,
streams, and rivers.
Soil properties are also affected by geologic re-working. The soils we have today are the
originally deposited geologic material modified by five soil forming factors: parent material,
climate, biota, topography, and time. The effects of the soil forming factors on the soil vary with
the soil’s location in the landscape (e.g.: ridge top, slope, toe, basin, etc.).
Infiltration characteristics at the land surface and shallow subsurface areas primarily depend
upon soil characteristics, geology, and surface drainage. These first layers of soil, and the
topography on which they lay, are the gateway to our groundwater. Once water has found its
way into the subsurface, its movement is governed by the confining or water bearing materials it
encounters.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
A.
Section 1, Page 15
Surficial Geology
Approximately 2 million years ago the topography of Scott County was formed in
sedimentary rock, consisting of broad, rolling plateaus divided by sharply cut valleys. An
artist’s sketch of that pre-glacial landscape is shown in the Scott County Geologic Atlas
series available from the University of Minnesota (http://www.geo.umn.edu/mgs/)
Today,
that landscape is buried and referred to, informally, as bedrock. It is covered by material
deposited by glaciers, known collectively as glacial drift.
A series of glacial advances and retreats deposited the drift by a combination of ice and
water action. Drift deposited by ice action alone is referred to as till. Drift deposited by
water action is outwash. Till may also be reworked by water after deposition by ice to
become outwash as well.
Drift thickness varies, from over 300 feet thick in the southern part of the County to
extremely thin near Savage. This glacially deposited material is very heterogeneous,
ranging from boulders and gravel to clay. Highly porous and permeable drift deposits
near the surface, such as sand and gravel, can become surficial aquifers when underlain
by less permeable clay-rich drift deposits. Clay-rich deposits impede downward water
movement, confining water to the porous drift material. Below the clay-rich deposits,
material that is more permeable may once again occur. These deposits often contain
groundwater under confined conditions. The glacial material is highly variable in its
water bearing characteristics, even over short distances and small changes in depth.
This variability in deposits resulted from several glacial advances and retreats over Scott
County and the mixture of till and outwash deposits. Outwash deposits are the result of
water running out from melting glacial ice, similar to the material deposited in street
gutters during the spring thaw every year. Usually, outwash consists of porous sands and
gravels containing today’s glacial drift aquifers.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 16
The County’s Geologic Atlas shows the results of a transect taken on a line from east of
New Prague to just south of Murphy Lake. The mixture of layers shown and the
accompanying description illustrate the complex mixture of material composing the
glacial drift of Scott County.
B.
Bedrock Geology
Beneath the glacial deposits lie a series of layered sedimentary rocks. The youngest
layers are on top and the oldest at the bottom. Beneath the sedimentary rock is volcanic
(igneous) rock.
The County Geologic Atlas shows a stratigraphic section that describes the different
layers of bedrock that are found beneath the glacial drift. Map 4 shows locations of these
bedrock formations in Scott County. The general process that resulted in these bedrock
layers is described below.
About 1,100 million years ago, molten volcanic rock in our area solidified. These lava
flows are known as the Chengwatana Volcanic Group. They are believed to be thousands
of feet thick and underlie the other sedimentary bedrock formations in the County, except
for an area west of Belle Plaine, trending south to north. There, the sedimentary deposits
are worn away and a segment of the volcanic rock is exposed directly to the glacial drift.
Over the next 100 million years or so, the Chengwatana Volcanic Group was subjected to
faulting, uplifting and weathering forces which lead to erosion and subsequent deposition
of thick layers of reddish colored muds and sands. The deposits are known as the Solor
Church Formation and are the oldest sedimentary layer in the County.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 17
On this formation sits the bedrock of most groundwater interest.
A very general
description of the process that produced it follows.
From 950 million years to 470 million years ago, the area encompassing Scott County
was the bottom of a large inland sea. The portion of the sea that covered Scott County
and southern Minnesota is known today as the Hollandale Embayment. Over millions of
years this sea expanded and reduced in size. These changes had profound effects on the
nature of the deposited sea bottom sediments.
During periods when the sea was shallow, coarse-grained sediments were deposited.
These sediments form today’s water bearing bedrock aquifers.
In the same period, when the area of Scott County was farthest from shore, mudstones,
siltstones, and other fine-grained sandstones were deposited. These deposits today form
confining layers to the aquifers. At times, the inland sea became dry and the sediments
deposited to that point were exposed to long periods of weathering. The sea advanced
again and deposited new sediments on the weathered surface.
With the historical chronology of sediment deposition in mind, there are additional
geologic influences that affected this entire layered structure. The top (or youngest) eight
layers, deposited after 520 million years, have been tilted by subsidence and faulting of
the Chengwatana and Solor Church Formations. The bedrock layers run downslope from
SW to NE with an overall drop of up to 300 ft. This slope is part of a larger geologic
structure called the Twin Cities basin, which underlies the seven-county metropolitan
area. Scott County lies on the southwest flank of this geologic structure.
C.
Major Aquifers
There are four major aquifers in Scott County. They are, from newest to oldest, the
Glacial
Drift
Aquifer,
the
Prairie
Scott County Water Resources Plan – Amendment 1
du
Chien-Jordan
Aquifer,
the
October 2007
Land and Water Resource Inventory
Section 1, Page 18
Franconia-Ironton-Galesville Aquifer, and the Mt. Simon-Hinckley-Fond du Lac Aquifer.
Figure 1.4 describes the water quality of the three bedrock aquifers.
FIGURE 1.4: Groundwater Chemistry in Scott County
General description of water quality for the bedrock aquifers found in Scott
County (Woodward 1986)
Prairie du Chien – Jordan Aquifer
The Prairie du Chien Group and the Jordan Sandstone are hydrologically connected, because there is no regional
confining bed between them, and the common constituents in the water in both are quite similar. Local, small
hydrogeochemical differences may exist, however, due to the presence of some relatively impermeable beds of limited
extent.
The proportion of calcium-magnesium bicarbonate and the amount of total dissolved solids are strongly influenced by
the type and thickness of the overlying deposits. In the east, where the aquifer crops out or is overlain by thin Quaternary
deposits, the percentage of ions that is calcium-magnesium bicarbonate is highest and the total dissolved solids content is
the lowest. Here the downward and lateral movement of water is rapid and is in contact with the rocks rather briefly.
Toward the west, the total dissolved solids content increases as a result of recharge through thick Quaternary deposits and
younger bedrock aquifers. Here the predominant constituents calcium, magnesium, and bicarbonate are partially replaced
by sodium, potassium, and sulfate.
Franconia-Ironton-Galesville Aquifer
The ground water in the Franconia-Ironton-Galesville Aquifer is similar to that in the overlying Prairie du Chien-Jordan
aquifer. However, water percolating through the intervening St. Lawrence confining bed undergoes minor changes as
contact with its dolomitic shale and siltstone leads to further replacement of calcium, magnesium, and bicarbonate ions by
sodium, potassium, and sulfate ions. Like the Prairie du Chien-Jordan aquifer, this aquifer has lowest total dissolved solids
content in the east where the dominance of calcium, magnesium, and bicarbonate ions is greatest.
Data are lacking in the southern part of the aquifer and the pattern shown in this part of the map for distribution of
common hydrochemical constituents is an approximation.
Mt. Simon-Hinckley-Fond du Lac Aquifer
The ground water in the Mt. Simon-Hinckley-Fond du Lac aquifer is of the calcium –magnesium bicarbonate type. An
area where calcium, magnesium, and bicarbonate are a high percentage of the total ions and total dissolved solids content
is low occurs north of the Twin Cities as a result of rapid migration of ground water through sandy Quaternary deposits and
through unsaturated surface exposures of the aquifer. The lower percentage of calcium, magnesium, and bicarbonate
north of this area may reflect the relative lack of calcareous material in the overlying glacial deposits of the Superior lobe.
South and southwest of the Twin Cities, the percentage of calcium, magnesium, and bicarbonate ions decreases and
the amount of total dissolved solids increases, because the aquifer dips beneath the younger bedrock aquifers, and the
water has traveled through a thicker sequence of overlying materials. The high percentage of bicarbonate ions at the
junction of Waseca, LeSueur and Rice Counties probably is caused either by rapid lateral movement of water within the
aquifer itself or by relatively rapid downward circulation of water from the upper aquifers.
Two anomalies occur along the Mississippi River, where calcium, magnesium, and bicarbonate ions decrease below
70 percent of common constituents, and sodium, potassium, sulfate, and chloride ions together make up the remaining 30
percent. The change in chemical composition may reflect movement of ground water through the overlying shaly Eau
Claire confining bed or the presence of shaly material within the aquifer fabric.
Data for the southern part of the aquifer are lacking and this part of the map is more general than the maps presented
for the other Paleozoic aquifers in southern Minnesota.
The Scott County Geologic Atlas shows glacial drift and bedrock transects as described
in the previous section. These cross-sections illustrate how several bedrock aquifers,
through contact with glacial drift aquifers, could be contaminated if infiltrating water
from the surface traveled downward and made contact with the exposed end of a bedrock
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 19
aquifer. Glacial material is mostly pervious and thus most likely to allow pollutants to be
carried downward to bedrock aquifers.
D.
Groundwater and Surface Water Connections
1.
Flow Direction – Groundwater flow direction was determined from static water
levels that were recorded when wells were installed.
Groundwater flows
downhill, or, down a gradient, just as surface water does. Therefore, groundwater
flows from areas of high static water levels to areas of low static water levels.
There are two types of static water levels. In the first type, the water table is the
actual water surface (or static water level) in an unconfined aquifer. Lake levels
and wetlands are sometimes expressions of the water table. The unconfined
aquifers in Scott County are typically composed of shallow sand and gravel
deposits. The bedrock aquifers in Scott County usually have impermeable rock
above them, which confines the water in the aquifer. The elevation to which
water rises in a well that taps a confined aquifer is called the potentiometric
surface or the piezometric head and is the second type of static water level. Water
rises in the well above the top of the confined aquifer due to the internal water
pressure.
Maps in the Scott County Geologic Atlas, as amended, show transmissivity,
potentiometric surface, direction of groundwater flow in major aquifers, and a
general description of water chemistry of County’s bedrock aquifers. Additional
sources of geologic information for Scott County are the Minnesota Geological
Survey (MGS), United States Geological Survey (USGS), Minnesota Pollution
Control Agency (MPCA), and the County’s Community Development Division.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
2.
Section 1, Page 20
Geologic Sensitivity – Surface water and groundwater are part of a hydrologic
single system. If not sited or maintained properly, surface water management
structures, such as infiltration basins, holding ponds, reclaimed gravel pits, or
wetland replacements, may adversely affect groundwater quality.
Map 5
illustrates where bedrock formations are susceptible to contamination in Scott
County.
Stormwater runoff poses a threat to groundwater contamination. As stormwater
runs through streets, parking lots, outdoor storage areas, and lawns, it collects an
entire spectrum of organic and non-organic substances. Oils, heavy metals, lawn
chemicals, and animal wastes are a few of the substances carried in stormwater
runoff. Stormwater runoff in urban areas can contain bacteria, nitrates, chlorides,
lead, chromium, and other contaminants.
Stormwater that is discharged into holding ponds or infiltration basins can seep
into surficial aquifers or bedrock aquifers where the bedrock is near the surface.
Integrating groundwater protection with surface water management will help
prevent groundwater contamination and reduce the potential cost of remedial
action.
E.
General Topographic Relief
The advance and retreat of glacial ice sheets, the remnants of terminal moraines, and
subsequent dissection by streams and rivers has left much of the present day topography
in Scott County rolling to strongly rolling.
The rolling topography provides for generally good drainage throughout most of the
County. However, due largely to the advance and retreat of glacial sheets, the geology of
the area is extremely complex and contains areas of fine textured soils, clay lenses and
high or perched water tables. Consequently, there are many small closed basins with
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 21
small ponds or wetlands throughout the County. These are especially prevalent in the
lower elevation portions of the County such as Savage, and the northern part of Credit
River Township. In the past, the principal land use in this part of the watershed was
small subsistence farms.
F.
Bluff Features
Centuries of erosive actions by the Minnesota River and its tributaries have left unique
bluff features across areas of Scott County, most notably in the southwest corner of the
County in Blakely Township. These bluff areas offer unique views of the County and
contain the majority of the natural communities and rare species identified in the County
Biological Survey (Map 16).
These bluff features present many challenges for
stormwater management and erosion control as the areas around them become developed.
It is important that these areas are managed appropriately to preserve the unique features
including the natural communities and rare species.
IV.
Soils
A.
General Soils
Soil associations represent several soil series having similar characteristics on a
countywide basis. In 1980, a revised soil association map for Scott County was
published (USDA 1980) delineating 10 soil associations (Map 6).
Several
changes have been made from the 1959 soil association map due to more recent
investigations and interpretations.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 22
FIGURE 1.5: Soil Associations in Scott County
(from the USDA SCS, 1980)
General characteristics of the ten soil
associations are shown in Figure 1.5. A
soil series is a more detailed soil
classification than a soil association.
Individual soil series for Scott County
were published in 1959 (USDA 1959) as
part of the Scott County Soil Survey.
Scott County, like any other county in the
State, has its share of erosion prone areas.
The Scott SWCD and the Natural
Resources
Conservation
Services
(NRCS) have spent considerable efforts
to characterize erosion prone areas. For
the most part, defining erosion prone area
begins with a soils map. Steep slopes are
susceptible to erosion and some soil
types are more erodible than others are.
Map 7 shows erosion prone areas within
Scott County.
B.
CORDOVA (WEBSTER)LESTER-CLARION:
Fertility, organic matter
content, and available water
capacity are high. The main
concern of management is
improvement of drainage and
erosion control.
COPASTON (COPAS)FAXON:
Shallow soil limits rooting
depth. Fertility is low and
organic matter content is high.
Available water capacity is low
for Copaston and the water
table is high in Faxon.
LESTER-CORDOVA
(WEBSTER)-HAYDEN:
Fertility and organic matter
content are moderate to high.
The available water capacity is
high. The main concerns of
crop management are control
of erosion and drainage of wet
areas
ALLUVIAL LANDDORCHESTER:
Wetness and flooding cause
this association to be high risk
for cultivated crops. Main
concerns of management are
wetness, flooding, and
sedimentation.
HAYDEN-LESTER-CARON:
Fertility and organic matter
content are high to low. The
available water capacity is
high. The main concerns of
management are control of
erosion on slopes and
drainage of low areas.
HEYDER (HAYDEN)KINGSLEY-MAHTOMEDI
(SCANDIA):
Organic matter content is low
on all upland soils. The main
concerns of management are
control of erosion and
adaptation to droughtiness.
HAYDEN-LESTER-TERRIL:
Organic matter content and
fertility are low. Available
water capacity is high. Main
concerns of management are
control of sheet and gully
erosion
ESTHERVILLE-BURNSVILLELESTER:
Organic matter content is
medium to low. Groundwater
pollution is a severe hazard on
the Estherville and Burnsville
soils where onsite sewage
systems are used.
HUBBARD-DAKOTAESTHERVILLE:
Fertility, organic matter
content, and available water
capacity are medium to low.
Main concerns of management
are droughtiness, control of
wind erosion, and improving
fertility.
ERIN-KILKENNY-CARON:
Fertility and organic matter
content are medium to high.
The available water capacity is
high. The main concerns of
crop management are control
of erosion, drainage of wet
areas, and maintenance of
surface tilth.
Prime Farmland
Prime farmland is defined as land that has the best combination of physical and chemical
characteristics for producing crops.
The soil has acceptable acidity or alkalinity,
acceptable salt and sodium content and few or no rocks.
Scott County Water Resources Plan – Amendment 1
The farmlands are not
October 2007
Land and Water Resource Inventory
Section 1, Page 23
excessively erodible or saturated with water for long periods. Examples of soils that
qualify are Clarion loam, Webster clay loam, and Tama silty clay loam. In Scott County,
there is a total of 110,000 acres of prime farmland, which represents 46 percent of the
County’s acreage.
C.
Hydric Soils
The location and extent of hydric soils in Scott County is shown on Map 8. Hydric soils
are soils that formed under conditions of saturation, flooding, or ponding long enough to
develop anaerobic conditions in the upper part of the soil profile. They are used as one
component (out of three) in identifying wetland areas.
Hydric soils have specific
indicators that are used for identification in the field, although many soil series are
designated as hydric. The County has used hydric soil classifications in its development
regulations related to density.
V.
Surface Water Resource Data
A.
Public Waters
Public waters are defined in Minnesota Statues, Chapter 103G.005 to include:
1)
water basins assigned a shoreland management classification by the
Commissioner of Natural Resources under MN Statutes, Chapter
103F.201 to 103F.221, except wetlands less than 80 acres in size that are
classified as natural environment lakes;
2)
waters of the state that have been finally determined to be public waters or
navigable waters by a court of competent jurisdiction;
3)
meandered lakes, excluding lakes that have been legally drained;
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
4)
Section 1, Page 24
waterbasins previously designated by the Commissioner of Natural
Resources for management for a specific purpose such as a trout lakes and
game lakes pursuant to applicable laws;
5)
waterbasins located within and totally surrounded by publicly owned
lands;
6)
waterbasins where the State of Minnesota or the federal government holds
title to any of the beds or shores, unless the owner declares that the water
is not necessary for the purposes of public ownership;
7)
waterbasins where there is a publicly owned or controlled access that is
intended to provide public access to the water basin;
8)
natural and altered watercourses with a total drainage area greater than
two square miles;
9)
natural and altered water courses designated by the Commissioner of
Natural Resources as trout streams; and
10)
public waters wetlands, unless the statute expressly states otherwise.
A public water designation does not:
1)
grant the public additional or greater right of access to the waters;
2)
diminish the right of ownership or usage of the beds underlying the
designated public waters;
3)
affect state law forbidding trespass on private lands; and
4)
require the commissioner to acquire access to the designated public waters
under MN Statutes, Section 97A.141.
Not withholding specific exceptions related to wetlands (MN Statutes, Sections
103G.221-103G.235), public waters may not be drained, and a permit authorizing
drainage of public waters may not be issued, unless the public waters to be drained are
replaced by public waters that will have an equal or greater public value.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 25
Penalties may be imposed if:
1)
the course, current, or cross-section of public waters of the state are altered
or appropriated without previously obtaining a permit from the
Commissioner of Natural Resources;
2)
if the course, current, or cross-section of public waters of the state are
altered or appropriated in violation or in excess of a permit issued by the
Commissioner of Natural Resources;
3)
if the course, current, or cross-section of public waters of the state are
altered or appropriated after a permit to undertake such activities are
denied by the Commissioner of Natural Resources; or
4)
if any other provision of MN Statutes, Chapter 103G are violated.
Maps of public waters in Minnesota counties are filed with the auditors of the respective
counties.
B.
Public Ditch Systems, Dams, and Control Structures
Public ditch systems include ditch systems, tile systems, judicial ditches, county ditches,
and joint county ditches provided for under MN Statutes, Chapter 103E. This chapter
does not include authorities for ditches created for roadway drainage, private ditches, or
ditches created as part of a municipal stormwater conveyance system. Map 9 shows
public ditches in the County.
The MnDNR Division of Waters maintains a dam inventory list for all of Minnesota.
Table 1.2 lists the dams in Scott County listed in this inventory.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 26
TABLE 1.2: Scott County Dam Inventory (taken from MnDNR-Waters "MN Inventory of Dams", 10/06/97)
Dam Name
Cedar Lake
Dvorak Wildlife Pond
Henry Pond
Hilgenberg Pond
Jeffers Fish Pond
Jeffers Wildlife Pond
Maxa Pond
Pettit Wildlife Pond
Ruehlings Pond
Sand Creek
C.
National
ID
MN00399
MN00276
MN00639
MN00636
MN00285
MN00284
MN00840
MN00280
MN00283
MN00535
Nearest
Town
TR-Sand Creek
Helena
TR-Sand Creek, Offstream Jordan
TR-Vermillion
Farmington
TR-Minnesota Lake
LakeviIlle
TR-Pikes (sic) Lake
Prior Lake
TR-Pikes (sic) Lake
Prior Lake
TR-Vermillion
Farmington
TR-Vermillion, Offstream Farmington
TR-Minnesota River
Belle Plaine
Sand Creek
Jordan
River or Stream
Owner Name
State of MN
Anton Dvorak
Wallace Henry
Wally Hilgenberg
Robert Jeffers
Robert Jeffers
Steve Maxa
Duane Petit
Earl Ruehling
City of Jordan
Downstream
Last
Hazard
Inspected
Low
Low
Low
Significant
6/28/95
Low
Low
Low
Low
Low
Significant
6/28/95
Wetlands
Wetland rules and regulations are contained in Minnesota Statutes, Chapter 103G.2212373 (Wetland Conservation Act) and in Minnesota Rules, Chapter 8420. Additional
wetland regulations apply as they relate to federal programs and authorities including
those administered by the COE, United States Fish and Wildlife Service (USFWS), and
USDA.
These regulations outline permitted activities, limitations, exemptions, and
replacement requirements for activities impacting wetlands.
Local governmental units (LGUs) are responsible for making exemptions and no-loss
determinations and approving replacement plans. MN Rules Chapter 8420.0200, para. B,
provides that within the seven-county metropolitan area, cities, townships, or watershed
management organizations can be delegated the enforcement responsibilities of the
Wetland Conservation Act (WCA). Within the unincorporated area of Scott County, the
townships, with the exception of Sand Creek, are the delegated authorities for local
activities related to the WCA. Sand Creek Township has transferred authority to the
Scott WMO.
Wetlands located by the SWCD within Scott County are shown in Map 10, with the
exception of the Minnesota River valley. Future mapping projects within the County will
provide more accurate locations of these wetlands. Wetlands are regulated and protected
under Minnesota Statute and Rule.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 27
The USFWS has defined eight types of wetlands. All eight types are known to occur in
Scott County. The following are descriptions for the eight types:
Type 1. Seasonally Flooded Basins or Flats
The soil is covered with water, or is waterlogged, during variable seasonal periods, but
usually is well drained during much of the growing season. This type is found both in
upland depressions and in overflow bottomlands. In the uplands, basins or flats may be
filled with water during periods of heavy rain or melting snow. Vegetation includes
smartweeds, wild millet, fall panicum, tealgrass, ragweed, and cockleburs.
Type 2. Inland Fresh Meadows
The soil usually is without standing water during most of the growing season, but is
waterlogged within at least a few inches of its surface. Meadows may fill shallow lake
basins, sloughs, or farmland sags, or these meadows may border shallow marshes on the
landward side. Vegetation includes grasses, sedges, rushes, and various broad-leaved
plants such as carex, prairie cordgrass, and mints. Wild hay oftentimes is cut from such
areas.
Type 3. Inland Shallow Fresh Marshes
The soil is usually waterlogged during the growing season; often covered with as much as
six inches or more of water. These marshes may nearly fill shallow lake basins or
sloughs, or they may border deep marshes on the landward side. They may contain water
up to midsummer, at which time they may dry up completely or remain waterlogged for
the rest of the season. Vegetation includes grasses, bulrushes, spikerushes, and various
other marsh plants such as cattails, arrowheads, pickerelweed, and smartweeds. In some
cases, cattails or bulrushes completely vegetate a marsh area. Other times, a narrow
fringe of cattails runs around a small open water area. In “dry” years these areas are
sometimes cropped.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 28
Type 4. Inland Deep Fresh Marsh
The soil is covered with six inches to three feet or more of water during the growing
season. These deep marshes may almost completely fill shallow lake basins, potholes,
limestone sinks, and sloughs, or they may border open water in such depressions.
Vegetation includes cattails, reeds, bulrushes, spikerushes, and wild rice. In open areas,
pondweeds, naiads, coontail, water milfoil, duckweed, water lilies, or spatterdock may
occur. Scattered clumps of cattails and bulrushes are common throughout a deep fresh
marsh.
Type 5. Inland Open Fresh Marsh
Shallow ponds and reservoirs are included in this type. Water is usually less than ten feet
deep and is fringed by a border of emergent vegetation. Vegetation includes pondweeds,
naiads, wild celery, coontail, water milfoil, muskgrass, water lilies, and spatterdock.
Type 6. Shrub Swamps
The soil usually is waterlogged during the growing season, and is often covered with as
much as six inches of water. Shrub swamps occur mostly along sluggish streams and
occasionally on flood plains.
Vegetation includes alders, willows, buttonbush,
dogwoods, and swamp-privet.
Type 7. Forested Swamps
The soil is waterlogged to within a few inches of the surface during the growing season,
and can be covered with as much as a foot of water. Typical trees include tamarack,
white cedar, black spruce, balsam, red maple, and black ash.
Type 8. Bogs
The soil is waterlogged and supports a spongy covering of mosses. This type occurs
mostly in shallow basins, on flat uplands, and along sluggish streams. Vegetation is
woody or herbaceous or both.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 29
In 2003, the SWCD completed an inventory of drained and altered wetlands in Scott
County. The data is available through the SWCD office and on the Scott County web
site.
D.
Flooding
FEMA provides flood insurance to citizens living in communities that participate in the
National Flood Insurance Program (NFIP). Communities enrolled in the NFIP must
adhere to certain standards and guidelines aimed at mitigating damages from flood
events. Once the community adopts these standards, citizens of that community may
then purchase flood insurance from the federal government via the NFIP.
FEMA contracts to have Flood Insurance Rate Maps (FIRM) created for these
communities, outlining which portions of the community are at high risk for flood
damage. Map 11 outlines these high-risk portions of the County.
All unincorporated areas within Scott
County, as well as most cities, are
currently enrolled in the NFIP. Figure
1.6 lists these communities, as well as the
date of their most current FIRM. Major
flood events in Scott County have
occurred along the Minnesota River
FIGURE 1.6: Communities in the NFIP
Community Name
City of Belle Plaine
City of Jordan
City of New Prague
City of Prior Lake
City of Savage
City of Shakopee
Scott County
Effective Map Date
Dec. 18, 1986
Jan. 6, 1982
July 21, 1999
Nov. 19, 1997
June 18, 1980
Sept. 29, 1978
Feb. 19, 1987
Elko and New Market are not in the NFIP.
For the most up-to-date list, please see:
http://www.fema.gov/fhm/tsdindex.shtm
several times in the past 60 years. Most
of these events occur in early spring, due to snowmelt and rainfall upon frozen or
saturated soils. Figure 1.7 illustrates the discharge history of the Minnesota River at
Jordan since 1935. Current streamflow data is available from USGS at:
http://waterdata.usgs.gov/mn/nwis/current/?type=flow
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 30
FIGURE 1.7: Minnesota River Discharge at Jordan, MN (data from USGS Gaging Station #05330000)
120000
117,000 cfs (4/12/65)
100000
90,900 cfs
(6/25/93)
81,900 cfs
(4/12/97)
84,500 cfs (4/14/69)
Discharge (cfs)
80000
72,200 cfs
(4/19/01)
62,900 cfs (4/11/51)
60000
59,100 cfs (4/16/52)
40000
20000
0
Oct-01
Oct-97
Oct-93
Oct-89
Oct-85
Oct-81
Oct-77
Oct-73
Oct-69
Oct-65
Oct-61
Oct-57
Oct-53
Oct-49
Oct-45
Oct-41
Oct-37
Oct-33
VI.
Land Use and Public Utility Services
A.
Existing Land Uses
Before pioneer settlement, the majority of land in Scott County was forested.
A
pre-settlement vegetation map (Map 3), has been compiled by the MnDNR based on
survey descriptions from approximately 1855. While Scott County is now predominately
agricultural, the northern cities along the Minnesota River are experiencing rapid urban
development.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Today, there are many competing land uses in the County.
Section 1, Page 31
As the Twin Cities
Metropolitan Area continues to grow, more development pressure will be placed on the
resources within Scott County, necessitating increased awareness of development effects.
Map 12 illustrates current land use in Scott County and Map 13 shows current Scott
County Zoning.
B.
Land Cover
The Minnesota Land Cover Classification System (MLCCS) is a relatively new tool that
fills an important information niche of great utility to natural resource managers and
planners. Developed by the Minnesota Department of Natural Resources in conjunction
with other state, federal, and local agencies, the system is unique in that it categorizes
urban and built up areas in terms of land cover, rather than land use. Land cover data
provides useful information about the vegetation and amount of impervious surface for a
given parcel of land. This information can be used in various analyses such as calculating
total impervious surface in a sub-watershed for rate and volume control or identifying
ecologically sensitive corridors for protection and restoration.
MLCCS data has been collected throughout Scott County. The information is currently
being analyzed for accuracy so that the data can be used by County staff as well as the
general public. Scott County will provide this information as part of its web based
Geographic Information System (GIS) tool that is available to the general public via the
County’s web site. This will allow users to access multiple layers of information such as
MLCCS, wetlands, hydric soils, etc.
C.
Anticipated Land use
Scott County 2020 Comprehensive Plan Update was adopted and approved by Scott
County in May 2001. The Comprehensive Plan addresses issues on future land use in the
11 townships, population projections, and plans for roads, parks and open space, and
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 32
other public services (Map 14). The County’s Planning Department is in the initial
stages of the 2030 Comprehensive Plan Update which is scheduled for adoption in 2007.
Any updates to the Comprehensive Plan that may affect water resource management will
be incorporated into future updates of this Local Water Plan.
VII.
Water-based Recreation Areas and Land Ownership
A.
Existing and Proposed Local, Regional, State, and Federal Parks,
Preserves, Wildlife Areas, and Recreational Areas
Scott County offers numerous opportunities for outdoor recreation. Parks, recreation
areas, and wildlife refuges abound throughout the County. Many of the lakes within the
unincorporated areas of the County are accessible to boats (see Table 1.3), increasing the
already abundant recreation choices for residents of this area.
TABLE 1.3: Public Boat Accesses and Fishing Piers (from MnDNR’s “Twin Cities Water Recreation Map”)
Water Body
Cedar
Cedar
Cedar
Cleary
Parking
Spaces
10
30
35
198
Park
Permit
no
no
no
permit
24 hours
24 hours
Carry in
Fishing
Amenity
shore
shore
pier
pier
Concrete
shore
12
no
24 hours
Concrete
Asphalt
Concrete
shore
shore
shore
shore
shore
pier
shore
shore
6
9
10
20
12
15
4
26
no
no
no
no
no
no
no
No
24 hours
24 hours
24 hours
shore
15
No
pier
15
no
Concrete
Concrete
♦
Fish
McMahon
MN River
MN River
MN River
O’Dowd
O’Dowd
Pleasant
Spring
Access
♦
Concrete
Earth
Concrete
♦
Spring
Thole/Schneider
♦
Concrete
Hours
24 hours
24 hours
24 hours
24 hours
Operating
Agency
MnDNR
MnDNR
MnDNR
Three Rivers
Park District
MnDNR
Phone
Number
651-772-7935
651-772-7935
651-772-7935
763-559-9000
651-772-7935
MnDNR
Shakopee
MnDNR
Shakopee
MnDNR
Shakopee
MnDNR
MnDNR
651-772-7935
952-445-2742
651-492-6400
952-445-3650
651-772-7935
952-445-2742
651-772-7935
651-772-7935
MnDNR
651-772-7935
MnDNR
651-772-7935
( Surface water management for these water bodies currently provided by the respective Watershed District)
There are two Regional parks within the unincorporated areas of Scott County: MurphyHanrehan Park Reserve and Cleary Lake Regional Park, which are managed by the Three
Rivers Park District. Murphy-Hanrehan Park Reserve is a 2,536-acre facility located in
the northeast part of the County. The Credit River flows through the western portion of
the park reserve. There are three lakes within the park, the largest being Hanrehan Lake.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 33
Cleary Lake Regional Park is a 1,048-acre natural area also located in the northeast part
of the County. The central feature of the park is the 137-acre Cleary Lake. The County
is also in the process of acquiring property for the Doyle-Kennefick Regional Park. The
park is not currently open to the public. In addition to the Regional Parks, numerous other
areas in the County provide recreation opportunities (Map 16). Figure 1.8 lists these
areas in the County.
FIGURE 1.8: Recreational/Wildlife/Scientific Areas
FEDERAL-USFWS:
MN Valley National Wildlife Refuge
STATE - MnDNR:
St. Lawrence State Wayside
Blakeley State Wayside
Clarks Lake Wildlife Management Area (WMA)
Habitat Module WMA
Mahoney WMA
Raven WMA
PF Module #3 WMA
Michel WMA
Karnitz WMA
STATE–MnDNR (con’t):
Marsh WMA
Bradshaw Lake WMA
St. Patrick WMA
Spartina WMA
REGIONAL–THREE RIVERS PARK DISTRICT:
Murphy-Hanrehan Regional Park
Cleary Lake Regional Park
TOWNSHIP PARKS
The MnDNR – Metro Wildlife Corridors has identified significant portions of Scott
County as having potential to become part of a regional Greenways system. The primary
purposes of the regional Greenways system are to conserve native landscapes,
ecosystems, and their species and to link parks, open spaces, wildlife corridors and
recreational trails.
By doing this, the ecological resources, the outdoor recreation
amenities, and the open-space character of the Twin Cities Metropolitan Region are
preserved and enhanced (Map 17).
B.
Fish and Wildlife Habitat
Twenty major lakes and numerous water basins are located within Scott County. In
general, most lakes in the County are considered eutrophic. The MnDNR, the MPCA,
and the Metropolitan Council have monitored several water bodies for fisheries success
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 34
and water quality information. Table 1.4 lists priority water bodies and summarizes
available monitoring information.
Please refer to Appendix E, Lake Water Quality
Report, of the Scott WMO Comprehensive Water Resource Plan (2004) for detailed
results of the monitoring activities. (♦Surface water management for these water bodies
currently provided by the respective Watershed District)
TABLE 1.4: Water Body Information
Water Body
Information Available
Cedar Lake
•
•
Fisheries Report
Water Quality
Cleary Lake
•
•
Fisheries Report
Water Quality
Credit River
•
•
Streamflow
Water Quality
Cynthia Lake
•
•
Water Quality
Fisheries Report
East Branch Raven Stream
•
Streamflow
Fish Lake♦
•
Gifford Lake♦
Monitoring Agencies
•
•
•
•
•
•
•
•
MnDNR
MPCA
Metropolitan Council
MnDNR
MPCA
Metropolitan Council
USGS
Metropolitan Council
•
•
•
•
MnDNR
MPCA
Metropolitan Council
USGS
Water Quality
•
•
•
•
•
Fisheries Report
•
MnDNR
MPCA
Metropolitan Council
Prior Lake-Spring
Lake WD
MnDNR
Markley Lake
•
Water Quality
•
•
Metropolitan Council
MPCA
McMahon Lake
•
•
Water Quality
Fisheries Report
Minnesota River
•
•
Streamflow
Water Quality
•
•
•
•
•
•
MnDNR
MPCA
Metropolitan Council
USGS
Metropolitan Council
US Army Corps of
Engineers
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Water Body
Section 1, Page 35
Information Available
Monitoring Agencies
Murphy Lake
•
•
Fisheries Report
Water Quality
•
•
MnDNR
MPCA
O’Dowd Lake
•
•
Fisheries Report
Water Quality
Pleasant Lake
•
•
Water Quality
Fisheries Report
Raven Stream (trib.)
•
Streamflow
•
•
•
•
•
•
•
MnDNR
MPCA
Metropolitan Council
MnDNR
MPCA
Metropolitan Council
USGS
Sand Creek
•
•
Streamflow (trib.)
Water Quality
•
•
USGS
Metropolitan Council
Thole / Schneider Lake
•
•
Water Quality
Fisheries Report
Unnamed Lake(MnDNR #70-11)
[Credit River Twp., Sec. 10]
•
Water Quality
•
•
•
•
•
MnDNR
MPCA
Metropolitan Council
MnDNR
MPCA
Vermillion River
•
•
•
Geomorphology
Water Quality
Flow
•
•
Scott County
VRWJPO
VIII. Unique Features
A.
Cultural Sites
St. Lawrence Project
Specifically, the project addressed transportation, settlement, ghost towns, and social and
economic conditions as they unfolded in the St. Lawrence town site. Central to the
project is the restoration of the Strait House in St. Lawrence as an interpretive center of
the dramatic history that occurred in the lower Minnesota River Valley. The MnDNR
and Scott County Historical Society collaborate with these special plans for the Lawrence
Wayside of the Minnesota Valley State Recreation Area. The Minnesota River Valley
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 36
Historic Restoration Project has been funded by a federal grant under the Intermodal
Surface Transportation Enhancement Act. State and local funding has been raised to
secure the grant. This project, which brings together the cooperative efforts of the
Minnesota Department of Natural Resources, Minnesota Department of Transportation,
and the Scott County Historical Society, is located in St. Lawrence Township, between
Belle Plaine and Jordan, north of U.S. Highway 169 and a mile west of the County Fair
Grounds on County Road 57.
B.
Critical Habitats and Scenic Areas
Hill’s Thistle, Cirsium Hillii, Prairie Site in Belle Plaine
A dry prairie remnant of the original expansive prairies that once covered the areas in and
around the city of Belle Plaine. This site has been identified as containing the Hills
Thistle, an endangered plant species.
Murphy-Hanrehan Park
The Murphy-Hanrehan Park Reserve and adjacent Cam Ram City Park are significant for
their natural characteristics. The park is home to several endangered species of animals
and plants. The most significant area of native vegetation in the park is large oak forest
on the rolling terrain that extends southeastward from Hanrehan Lake to the eastern
boundary of the park just north of Orchard Lake. The Minnesota County Biological
Survey has recently inventoried the natural communities in the park.
Louisville Swamp
This 2,600-acre unit has a unique mix of old fields, prairie remnants, oak savanna,
floodplain forest, and stone farmsteads. Historically, elk and buffalo grazed the oak
savannas, waterfowl filled the surrounding marshes, and the lakes teemed with fish.
Today, the most visible species is the beaver. Beavers have changed the landscape of this
area by damming and holding water, consequently hundreds of acres of trees have been
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 37
killed. Thirteen miles of trails cross through Louisville Swamp, favored by hikers in the
warmer months and cross-country skiers in the winter. There are four established trails:
Mazomani Trail, Mazomani Trail/Little Prairie Loop, Johnson Slough, and the State
Corridor Trail.
IX.
Pollutant Sources and Related Water Quality Information
Portions of this section were taken from the “Scott County, Minnesota Groundwater Protection
Plan”, adopted March 23, 1999 by the Scott County Board of Commissioners. Please see the
Groundwater Plan for additional information.
A.
Monitoring
Many different agencies perform a multitude of different monitoring activities in Scott
County.
In addition to the monitoring activities listed in Table 1.4, several other
agencies are involved in tracking different sources of pollution. The Scott SWCD in
Jordan monitors feedlot activity, the State Climatologist’s office maintains a network of
volunteer precipitation observers, and the U.S. Environmental Protection Agency (EPA)
monitors a variety of different pollutant quantities and sources.
B.
Feedlots
The MPCA defines a feedlot as “a lot or building or combination of lots and buildings
intended for the confined feeding, breeding, raising, or holding of animals and
specifically designed as a confinement area in which manure may accumulate, or where
the concentration of animals is such that a vegetative cover cannot be maintained within
the enclosure. For purposes of these parts, open lots used for the feeding and rearing of
poultry (poultry ranges) shall be considered animal feedlots.
Pastures shall not be
considered feedlots.”
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 38
As of January 2001, 271 feedlots over 10 animal units were inventoried by Scott SWCD.
See Map 18 for their general locations. There are 160 feedlots with 50 or more animal
units (10 or more units on shoreland) registered with MPCA. The County’s most recent
feedlot inventory (10 animals units or more) shows a total of 287 feedlots, however this
total is changing due to rapid development in many areas of the County.
C.
Unused, Unsealed Wells
Unused, unsealed wells are a major concern due to the ease with which contaminants can
enter the groundwater system. Unused, unsealed wells can act as direct channels for
surface pollutants to enter groundwater; bypassing the natural filtration and degradation
processes provided by soil and rock. Old well pits or dug wells have been used for the
disposal of chemicals and other hazardous substances. The top of smaller diameter
unused wells may be covered over, allowing contaminants to enter the groundwater
unnoticed. Unused, unsealed wells also constitute a physical danger. Mortgage lenders
and the State of Minnesota require disclosure of active, unused, and/or unsealed wells as
part of the disclosure statement for property transfers. At the time of property transfer, an
unsealed well must be properly sealed, brought back into use, or an annual unused well
permit must be obtained from the MDH.
Contamination can occur in an active well by improper construction or by back siphoning
of a contaminant. An improperly abandoned well can lead to issues due to improper
sealing around the outside of the casing, which leads to direct introduction of
contamination into the well, or by contamination leaking through rusted or corroded
casing and/or joints.
The proper maintenance and operation of wells and appropriate housekeeping in the areas
surrounding the wells are generally not considered by well owners/ operators. Proper
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 39
management of the well and surrounding area can prevent pollution from the surface
even if a well is not properly constructed.
The MDH requires notification or permitting of well construction and sealing and
regulates well drilling contractors. The program requires water well records and the
Minnesota Department of Health may inspect wells for proper construction, including
proper grouting, to ensure that wells are constructed according to the MDH Water Well
Code (MN Rules, Chapter 4725). The State of Minnesota regulations no longer allow the
construction of wells with an open annular space or a well screened through multiple
aquifers.
D.
Registered Storage Tanks
The MPCA Hazardous Waste Division-Tanks and Spills Section database is the most
current and accurate inventory of Underground Storage Tanks (USTs) in Minnesota. The
database is an inventory of tanks required to be reported by State rules and that tank
owners have voluntarily reported. MPCA reports that there are 45,000 USTs registered
in the state, but estimates that reported USTs represent only 75 percent of those installed
in the state. USTs that contain heating oil and are less than 1,100 gallons or USTs that
contain any other petroleum product or any other regulated substance and are less than
110 gallons are not required to be registered. The number of small unreported tanks is
unknown.
As of January 2001, the MPCA inventory reported that Scott County had approximately
911 active USTs and 600 inactive USTs. The registered USTs are distributed between
365 sites and are included in the database of the County’s Geographic Information
System (GIS).
Approximately 43.7 percent of all registered USTs are owned and
operated by service stations or bulk storage facilities. Approximately 31.1 percent of all
registered USTs contain gasoline, 29.4 percent contain diesel oil, 11 percent contain fuel
oil, and 29 percent contain other or unknown substances.
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
E.
Section 1, Page 40
Permitted Wastewater Discharges
The MPCA permits wastewater discharges. NPDES wastewater permit information can
be obtained from the MPCA.
F.
Individual Sewage Treatment Systems
In 1981, Scott County adopted the MPCA rules pertaining to individual sewage treatment
system (ISTS) construction. However, MPCA rules have essentially been enforced in the
County since 1978. Scott County also requires that compliance inspections be performed
whenever a building permit is applied for to expand an existing structure or add an
accessory building. As a result of these requirements, non-complying on-site systems are
being brought up to code.
ISTSs that are constructed too close to saturated soil conditions may threaten ground
water. Low infiltration rate soils are common within many areas of the County, holding
seasonal precipitation within the top ten feet of the soil profile.
ISTSs that are
constructed too close to perched water tables within these saturated soils also have the
potential to fail. There are also areas with highly permeable soils in close proximity to
limestone aquifers. Older type ISTSs, where deep cesspools had been used, are suspected
of causing nitrate and other contamination in these aquifers.
The County’s ISTS
ordinance specifies that ISTSs which pose a potential threat to groundwater be replaced
within specified time periods.
In May 2001, Scott County amended its land use philosophy to encourage Community
Sewage Treatment Systems (CSTS) that are managed by a public entity.
Public
management of CSTS is a positive step to ensure ongoing management of onsite
treatment.
G.
Cropland Erosion: Highly Erodible Lands
Scott County Water Resources Plan – Amendment 1
October 2007
Land and Water Resource Inventory
Section 1, Page 41
Several agricultural areas within Scott County are considered to be highly erodible,
according to the Scott County Soil Survey (USDA 1959), See Map 19 for location of
these areas.
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
Section 2, Page 43
Section 2
Coordination With Other Units of Government
I.
Scott County
Scott County, through its Natural Resources Department, Community Development Division,
Planning Commission, and County Board plans for the management, policies and
implementation for the protection of water and related land resources in the unincorporated areas
of Scott County including support for orderly annexation agreements. The Scott County Board
of Commissioners is the governing body for Scott County.
II.
Townships
A partnership arrangement has been in existence since 1969 between the 11 townships and Scott
County. The County has adopted a Comprehensive Plan and is the land use/zoning authority.
The townships are the road and stormwater authorities within their respective boundaries. Four
townships (Jackson, Credit River, Spring Lake, and Louisville) are also designated by the MPCA
as MS4 communities. The townships and the county collaborate on planning and operational
issues include erosion control programs.
III.
Scott County Role
In compliance with state law, the role of Scott County will be to set the standards for water
resource management that will be used to develop and implement their ordinances and plans.
The Scott County Water Resources Plan will provide management for the township areas within
the County. The County will coordinate implementation and permitting necessary to implement
this Plan.
Scott County will also be responsible for ordinance revisions, amendments, and
updates pertaining to the Scott County Water Resources Plan.
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
Section 2, Page 44
Scott County has entered into a Joint Powers Agreement with Dakota County to operate the
Vermillion River Watershed Joint Powers Organization. As a part of this agreement staff from
the County help administer the organization, and one of the Scott County Commissioners serves
on the Joint Powers Board along with two Commissioners from Dakota County.
A.
Planning
Scott County is committed to the preservation, improvement, management, and
development of water resources and related land resources. The County will promote the
goals and policies set forth in this Plan to preserve and enhance water quality, control
volumes and rates of runoff, and minimize, to the extent possible, the long-term cost of
managing water and related land resources.
The County encourages joint and
collaborative planning for the Urban Expansion Area around incorporated cities including
support for orderly annexation agreements. The County supports a seamless transfer of
authority related to water resource planning and management as annexation occurs.
B.
Impact of Implementation Programs
Scott County will develop a capital improvements program (CIP) to fund projects within
the County. The County will regulate (to the extent water resources are impacted) the use
and development of land through a review and permitting process managed by the
Planning Department. The Water Resources Plan shall be used as the minimum standard
for water planning within Scott County’s rural areas.
The County will provide implementation and enforcement in the township areas that are
under the land use authority of the County. This will be accomplished through the
adoption of amendments to the County Zoning Ordinance, and adoption of other
programs that support the goals and objectives within this Water Resources Plan. These
jurisdictions include:
the Scott WMO, Prior Lake-Spring Lake Watershed District
(PLSLWD), Lower Minnesota River Watershed District (LMRWD), and the Vermillion
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
Section 2, Page 45
River Watershed Joint Powers Organization (VRWJPO). It is the intention of Scott
County to work closely with the watershed jurisdictions in the County to avoid conflicts
and provide water management that is consistent and streamlined across jurisdictional
boundaries.
This Water Resources Plan has been reviewed and approved by the PLSLWD and the
Scott WMO, and reviewed by the LMRWD as of the date of this amendment (October
2007). The County has also updated its ordinances and official controls necessary to
implement the plan , and began implementation in 2006. Review of ordinances and
permitting and inspection procedures used by the County had been completed by the
PLSLWD who found them to be equivalent with PLSLWD procedures. A brief review
of ordinances was also completed by BARR Engineering on behalf of the VRWJPO. A
copy of their findings is included in Appendix C. As discussed in Appendix C the
County will address the findings of the BARR review and update ordinances within 120
days of approval of this plan by the VRWJPO. Changes necessary to address the gaps
may be completed as a county-wide ordinance or as an overlay district where Standards
are different from those of other watersheds.
The County anticipates using alternative approaches to satify some fo the ordinance gaps
identified.
Specific proposals and the rationale for equivalency are presented in
Appendix C.
C.
Review
Scott County will review development plans, erosion and sediment control plans, and
resource management plans to assess the effect to the water and associated land resources
in each watershed and ensure conformance with the Water Resources Plan. The Scott
County Development Review Team (DRT) will meet as needed to review proposed
development projects and is composed of members of the following groups: Natural
Resources Engineer, Environmental Health, Highway, Planning & Zoning, Building,
Township official, and occasionally a Township consultant.
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
IV.
Section 2, Page 46
Scott County Administrative Tasks
Scott County’s overview responsibility includes the following tasks (pursuant to MN Statutes
103B.211, 103B.231, 103B.235, and 103B.3369).
•
The County shall prepare, adopt, implement, and amend a plan consistent with the
requirements set forth in MN Statutes 103B.235 and MN Rules Chapter 8410. The Plan
period shall be five (5) years, commencing with the County’s water plan adoption. Plan
revision will begin at four (4) years after the date of adoption.
.
•
Scott County shall review and approve ordinances with respect to the following general
guiding principles:
1.
Protection of drinking water.
2.
Control and limit erosion and sedimentation.
3.
Promotion of natural infiltration of precipitation and stormwater.
4.
Control rates and volumes of runoff to specified standards.
5.
Protection and enhancement of recreational water uses and facilities.
6.
Protection of fish and wildlife habitat.
7.
Management of capital expenditures to be as effective and efficient as possible for
management of water and related land resources.
8.
Secure other benefits associated with proper surface and groundwater
management.
V.
Intergovernmental and Institutional Relationships of Scott
County
Scott County’s plan applies to the unincorporated areas of Scott County which is comprised of
four watershed jurisdictions. Watershed jurisdictions include the Scott WMO, the two watershed
districts (Lower Minnesota River and Prior Lake-Spring Lake), and a portion of the Vermillion
River Watershed.
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
A.
Section 2, Page 47
Scott WMO
Scott County will work with the Scott WMO to provide the necessary water management
and enforcement to areas that are under the County’s jurisdictions.
B.
Watershed Districts
Scott County will coordinate with the PLSLWD and LMRWD on CIPs and permit
programs to avoid duplication and promote joint cooperation and communication across
the County. Table 2.1 compares the various watershed jurisdictions in Scott County.
Table 2.1: Comparison of Scott County Watershed Jurisdictions
Scott Water
Management
Organization
Area (sq. miles)
in Scott County
Plan date
287.1
287.1
February 2004
Lower
Minnesota
River
Watershed
District
64
27.8
September 1999
Established
October 1996
March 1960
March 1970
Management
Scott County Board of
Commissioners as the
Scott WMO
Southwest, Sand
Creek, Shakopee
Basin, Credit River,
Prior Lake-Spring
Lake not in WD
5 managers
appointed by
County Boards
Areas directly
tributary to the
Minnesota River
5 managers
appointed by
County Board
Prior Lake and
Spring Lake
watersheds
Watersheds
served
C.
Prior LakeSpring Lake
Watershed
District
Vermillion River
Watershed Joint
Powers
Organization
42
42
February 1999
335
18.1
November 2005
Joint Powers
Organization 8/02
Joint Powers Board
(Scott & Dakota
Counties)
Vermillion River
watershed
Vermillion River Watershed
The Vermillion River Watershed covers a large portion of Dakota County and an area in
southeastern Scott County within New Market Township, which includes portions of the
Cities of Elko and New Market. In August 2002, Scott County and Dakota County
agreed on the joint administration and implementation of the former Vermillion River
WMO Watershed Management Plan. A Joint Powers Agreement is in place and a Joint
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
Section 2, Page 48
Powers Board, comprised of one Scott County Commissioner and two Dakota County
Commissioners provides for joint management of this watershed. A Watershed Planning
Commission was appointed for the Vermillion River Joint Powers Organization at the
end of 2002, which consists of nine members; eight from Dakota County and one from
Scott County. The VRWJPO Watershed Plan was approved November, 2005.
D.
Townships
Scott County will update it’s ordinances upon the adoption of this Water Resources Plan
and Rules and enforce ordinance standards on proposed developments. The County will
collaborate with all townships, who are the local stormwater authority in their respective
areas. The County will also collaborate with the Townships on wetland related issues for
those Townships who retain the WCA LGU authority.
E.
Cities
Scott County will work with Cities and Townships with annexation agreements to
evaluate the potential for downstream impacts resulting from development occurring
within a City and discharging into the unincorporated areas of the County.
F.
Cannon River Watershed
The Cannon River originates in Steele County and enters the Mississippi River in
Goodhue County at Red Wing. A small portion of its physical watershed (approximately
two square miles) is located within extreme southeastern portion of Scott County in New
Market Township. The Scott WMO will work with the Cannon River Watershed to
protect the headwaters of Cannon River. It should be noted, however, that the portion of
the North Cannon River Watershed that is in Scott County has been incorporated into the
political boundary of the Scott WMO according to historical documentation from BWSR,
the SWCD, and the former Sand Creek WMO.
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
G.
Section 2, Page 49
Shakopee Mdewakanton Sioux Community (SMSC)
The SMSC is a federally recognized Indian Tribe with sovereign control over its tribal
lands that are in trust and an inherent police power separate and distinct from that of the
State of Minnesota and its political subdivisions. The SMSC is required to manage its
tribal waters in accordance with federal regulations and tribal needs while coordinating
its monitoring and enforcement with applicable watershed authorities where necessary
and appropriate. The County will promote coordination with the SMSC for land in the
SMSC trust for mutual benefit whenever possible and will consider the SMSC’s concerns
in all projects that may affect their water resources, particularly with regard to stormwater
management and groundwater (drinking water supplies).
H.
NPDES MS4 Communities
Credit River, Jackson, Louisville, and Spring Lake Townships, along with Scott County,
have been identified by the MPCA as NPDES Phase II Municipal Separate Storm Sewer
System (MS4) communities. The MPCA has previously reviewed and approved the
Stormwater Pollution Prevention Plans (SWPPPs) for each of these communities. The
County worked with the Townships during the development of the SWPPPs by sharing
resources and may continue to do so in the future.
However, each township is
responsible for the material contained within their respective SWPPP. Each township has
designated a responsible party to ensure the minimum control measures are implemented
in accordance with the SWPPP. Each township is also responsible for submitting the
annual reports to the MPCA. The County does not enforce the implementation of the
township’s SWPPPs. In cases where the County does have involvement pertaining to the
Township’s MS4 SWPPP there shall be a written agreement between the two parties.
VI.
Regulatory Agencies
Several state and federal agencies are responsible for administering State or Federal laws and
regulations associated with water resources.
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
A.
Section 2, Page 50
Minnesota Board of Water and Soil Resources (BWSR)
BWSR is a state agency that assists local governments to manage and conserve their
irreplaceable water and soil resources.
BWSR provides local governments with
guidelines, training, and technical assistance in developing and administering resource
management plans and programs and provides state funding for water and soil
management carried out by local government. Through legislative initiative, the Board of
Water and Soil Resources seeks policies supportive of soil and water resource
management and encourages implementation of those policies through local units of
government. BWSR oversees WMOs, WDs, SWCDs, and administers the rules for the
Minnesota Wetland Conservation Act.
B.
Minnesota Department of Natural Resources (MnDNR)
The mission of the Minnesota Department of Natural Resources is to work with citizens
and local government to protect and manage the state’s natural resources, to provide
outdoor recreation opportunities, and to provide for commercial uses of natural resources
in a way that creates a sustainable quality of life. The DNR has many divisions, however
the Waters division is responsible for issues such as local water planning, the Protected
Waters Inventory, groundwater (including water appropriation), floodplains, shoreland
areas, and dam safety. In addition the Division of Ecological Services collects and
disseminates ecological information to provide decision makers with tools for making
informed resource decisions.
C.
Minnesota Pollution Control Agency (MPCA)
The MPCA was established in 1967. Its purpose is to protect Minnesota's environment
through monitoring environmental quality and enforcing environmental regulations. The
MPCA administers, among other things, the NPDES permit program, the Stormwater
Phase II NPDES rules, the NPDES General Construction Stormwater permit program,
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
Section 2, Page 51
ISTS regulations, feedlot regulations, and composes the list of the state’s impaired waters
for the EPA.
D.
Minnesota Department of Health (MDH)
The MDH administers several water-related programs including wellhead protection,
well management, and drinking water protection.
E.
Minnesota Department of Agriculture (MDA)
The MDA's mission is to work toward a diverse agricultural industry that is profitable as
well as environmentally sound; to protect the public health and safety regarding food and
agricultural products; and to ensure orderly commerce in agricultural and food products.
MDA helps farmers and homeowners by developing guidelines for soil amendments and
nutrient management to prevent excessive applications. MDA samples well water to
check for pesticides and contamination and tests soils to analyze their composition.
F.
Environmental Quality Board (EQB)
The EQB at Minnesota Planning draws together five citizens and the heads of 10 state
agencies that play a vital role in Minnesota’s environment and development. The Board
develops policy, creates long-range plans and reviews proposed projects that would
significantly influence Minnesota's environment.
The EQB administers Minnesota’s
environmental review program including Environmental Assessment Worksheets (EAW)
and Environmental Impact Statements (EIS).
The county supports area wide
environmental review to identify environmental and development issues and solutions
prior to major changes in land use, consistent with state law.
G.
U.S. Army Corps of Engineers (COE)
Scott County Water Resources Plan – Amendment 1
October 2007
Impacts on Other Units of Government
Section 2, Page 52
The mission of the COE is to provide quality, responsive engineering services to the
nation including planning, designing, building and operating water resources and other
civil works projects (navigation, flood control, environmental protection, disaster
response, etc.). The COE administers Section 10 of the Rivers and Harbors Act permit
program and Section 404 of the Clean Water Act (wetlands permit program).
H.
U.S. Environmental Protection Agency (EPA)
EPA's mission is to protect human health and to safeguard the natural environment — air,
water, and land — upon which life depends. EPA works closely with other federal
agencies, state and local governments, and Indian tribes to develop and enforce
regulations under existing environmental laws. EPA is responsible for researching and
setting national standards for a variety of environmental programs and delegates to states
and tribes responsibility for issuing permits, and monitoring and enforcing compliance.
Where national standards are not met, EPA can issue sanctions and take other steps to
assist the states and tribes in reaching the desired levels of environmental quality. The
Agency also works with industries and all levels of government in a wide variety of
voluntary pollution prevention programs and energy conservation efforts.
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
Section 3, Page 53
Section 3
Background and Assessment of Issues
I.
Introduction
As listed in the Executive Summary of this document and described in detail in Section 4, there
are eight goals associated with the Scott County Water Resources Plan.
While the goals
themselves are quite broad, the policies and objectives under each goal in Section 4 address
specific concerns for water resources. A list of specific issues of concern is provided below (in
no particular order), however it should be noted that, due to the universal nature of water, these
issues are interrelated with all of the goals.
•
•
•
•
•
•
•
Non-point source pollution
Erosion control
Groundwater preservation
Wetlands protection
Flooding
Feedlots
Education
The focus of this section is on the assessment of current issues within Scott County. The
assessment process, if done correctly, is first and foremost viewed as an on-going activity. It is
important to utilize existing data sources and evaluate existing data, but it is also necessary to
determine data needs as technology improves.
Second, a continual reassessment of data
collection opportunities and emerging methodologies is essential to providing the information
needed to make intelligent management and policy decisions.
Discussions regarding issues and on-going data collection and evaluation are important for the
County to gain understanding of the processes and external forces that affect our water resources.
However, it is critical that the general population within the County be apprised of and
understand the issues that are affecting their resources. The success of a water program will be
dependent upon the teamwork and communication of all parties. Therefore education at all
levels is an overall theme throughout this Water Plan.
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
II.
Background Information
A.
Sources of Pollutants
Section 3, Page 54
Pollutants originate from a variety of sources including but not limited to:
Urban sources:
•
•
•
•
•
•
Erosion from construction sites
Runoff from lawns and streets from residential development
Runoff from parking lots and streets from commercial development
Runoff, pollutant discharges, and air pollutant deposition from industrial development
Faulty ISTS
Impervious surfaces
Agricultural sources:
•
•
•
Discharges from known surface and subsurface tile drainage systems
Erosion or runoff from cropland, range land, feedlots, animal waste lagoons,
barnyards and pastures
Faulty ISTS
Other sources:
•
•
•
•
•
•
B.
Increased runoff and flow duration causing bank and bed degradation of
waterways/drainageways
Abandoned well contamination
Leaking hazardous materials and fuel storage tanks
Air pollutant deposition (e.g., acid rain), which includes sources outside the region
Salt and sand from winter street treatment; salt storage areas and snow storage areas
Excrement from wildlife and waterfowl (based on agency and university research)
Types of Pollutants
Pollutants that have a significant impact on the water quality of the County consist of several
specific types.
Sediment:
Sediment causes higher turbidity in water and causes a decrease in photosynthetic activity
in plants and aquatic life. Turbidity can be measured by the amount of light scattered or
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
Section 3, Page 55
blocked by suspended sediment and organic particles. Sources of suspended sediment
can include cropland erosion, construction site erosion, drainage ditch, stream, and
riverbank erosion, and stream and river channelization. Sediment is also a carrier for
nutrients flushed into the water due to erosion.
Nutrients:
The primary nutrients are phosphorus and nitrogen, but any element that is vital to plant
growth is considered a nutrient. Excessive amounts of nutrients in water can lead to
eutrophication. Eutrophication is caused by an increase in algal growth that causes a
decrease in oxygen concentration and an increase in turbidity. A significant decrease in
oxygen can kill fish and result in an increase in turbidity and can impair aquatic plant
growth. An example of oxygen depletion is the hypoxia area in the Gulf of Mexico, an
area of low dissolved oxygen (<2.0mg/l) spreading from the delta of the Mississippi
River along the Louisiana coast. Over time this area of water has become so depleted in
oxygen that little life is supported within the water column, with bottom-dwelling
organisms that can not leave the zone being affected most significantly due to stress
and/or death.
Sources of nutrients include fertilizers, detergents, leaves and grass clippings, feedlots,
pets, faulty ISTS, barnyards, pastures, manure storage facilities and waste lagoons,
wildlife, and waterfowl. Phosphorus compounds tend to bind to soil particles, therefore
controlling erosion will decrease the amount of phosphorous found in water bodies.
Nitrogen compounds are highly soluble and can quickly contaminate the groundwater if
excessive watering is used after fertilizing. Nitrogen compounds such as nitrate and
nitrite can be toxic to humans if contaminated runoff leaches into the groundwater. The
MDH’s web site, specifically the Drinking Water Protection page, has additional
information available on contaminant standards, contaminant health effects, drinking
water advisories, public water supply systems, as well as fact sheets on various other
water-related topics.
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
Section 3, Page 56
Pathogens:
The presence of pathogenic microorganisms is often characterized by determining the
population of fecal coliforms in water quality monitoring samples. Fecal coliforms are a
type of bacteria that are commonly found in the digestive tracks of most warm-blooded
animals and are used to identify water that is contaminated with fecal material. Sources
of fecal material include feedlots, pets, faulty ISTS, barnyards, pastures, manure storage
facilities and waste lagoons, wildlife, and waterfowl. State standards for fecal coliform
levels in water are 200 organisms per 100 ml of water (MN Rules Chapter 7050).
Pathogens have also been an issue in drinking water supplies due to inadequate filtration
within municipal water supply systems and in contaminated groundwater wells.
Organic material:
Large quantities of oxygen-demanding substances, such as pet wastes, street/lawn litter
and organic matter from urban runoff following a rainfall can be deposited in lakes or
streams as part of surface runoff. The potential for oxygen depletion is estimated by
using the 5-day biochemical oxygen demand (BOD5). BOD5 is a measure of the amount
of oxygen required by aerobic microorganisms to decompose the organic matter in a
sample of water. The resulting BOD5 value can be used as a measure of the degree of
water pollution.
Example sources of organic material that microorganisms use oxygen to decompose
include plant matter, animal waste, and discharges from faulty ISTS and wastewater
treatment plants.
With the increased food supply provided in organic matter,
microorganisms flourish. This increase in microorganisms depletes the oxygen level in
the water body more quickly than it can be replaced. Oxygen depletion as a result is a
common cause of fish kills.
Toxic Substances:
Certain types of industry release chemicals into the atmosphere that travel and disperse
over large areas.
Thus, contamination from Polychlorinated Biphenyls (PCBs) and
mercury is an issue throughout Minnesota lakes. The vast majority of mercury released
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
Section 3, Page 57
to the atmosphere comes from coal burning power plants and trash incinerators. This
elemental mercury enters the water supply and then is reduced by bacteria to methyl
mercury. Methyl mercury binds to fish gills and over time accumulates in their tissue.
Methyl mercury damages the central nervous system, especially in developing children
and infants, and can ultimately lead to death. PCBs were produced as an industrial
product until evidence was found that they accumulated in the environment, were
potential carcinogens, and disrupted the reproductive cycles of plants and animals. Due
to the PCBs not being readily biodegradable, they are still found in the environment
today although they have not been produced since the late 1970’s. PCBs are fat soluble
due to their hydrophobic characteristics and will build up in the fat stores of fish, making
them dangerous to eat.
Another source of toxic substances from industrial and commercial sites is petroleum
products from leaking USTs.
USTs have been used to store petroleum and other
hazardous substances since the early 1900’s.
Older USTs were subject to product
releases caused by inadequate corrosion protection.
Many of these releases went
unnoticed for long periods of time until the USTs were removed from the ground. State
law required that most USTs be upgraded to include leak detection monitors, spill
prevention equipment and corrosion resistance as of the year 2000; however, petroleum
and hazardous materials from historical releases or from unregulated or non-conforming
tank systems still have the ability to seriously impact groundwater.
In addition to the above sources, historical practices of disposal of chemicals directly
onto the soil surface, into soil pits, or floor drains, etc., has allowed solvents and other
hazardous materials to enter the soil and groundwater environment and has caused
contamination of these resources.
Although these types of practices are primarily
associated with older urbanized areas, old farm dumps are also common areas of
contamination.
Pesticides
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
Section 3, Page 58
Pesticides are widely used to manage unwanted plants, insects, and fungi.
While
pesticides are labeled for use and extensively field tested prior to commercial use, they
are, at times, used contrary to their labeling. If used unwisely, pesticides are known to be
toxic to humans and the environment.
Pesticides are generally considered nonpoint source contamination and are typically the
result of combined activities of many landowners within a watershed area and rarely can
be attributed to any single source. The MDA adheres to the Comprehensive Ground
Water Protection Act of 1989 (MN Statute Section 103H) and the Pesticide Control Law
(MN Statute Section 18B), which together require that MDA work to properly manage
pesticides and adequately protect groundwater from agricultural pesticides. This also
includes the development of Integrated Pest Management (IPM) programs. IPM is an
approach that first assesses the pest situation, evaluates the merits of pest management
options and then implements a system of complementary management actions within a
defined area. The goal of IPM is to mitigate pest damage while protecting human health,
the environment and economic viability. Therefore, IPM is a dynamic system that is
adaptable to diverse management approaches. Pest management decisions are made by
the individual producer, business entity or government agency but are influenced by the
diversity of public and private values (MDA, 2002).
The MDA is also charged with the development of management practices and regulatory
rules in the event that groundwater quality monitoring indicates significant degradation
trends. The agency is guided by a Pesticide Management Plan (PMP) to address impacts
to the state's water resources and guide development of Pesticide Best Management
Practices for the prevention, evaluation and mitigation of nonpoint source occurrences of
pesticides.
Accordingly, MDA pesticide management programs are intimately linked to the
Groundwater and Surface Water Monitoring Programs. The MDA’s web site contains
Scott County Water Resources Plan – Amendment 1
October 2007
Assessment of Issues
Section 3, Page 59
further information regarding pesticides and pesticide use including an article on
Voluntary Best Management Practices for Pest Control in Agronomic Crops.
Temperature
While the unincorporated areas of Scott County do not contain designated trout streams;
portions of the Vermillion River in Dakota County downstream of Scott County are
designated.
The designated trout stream area was recently expanded and trout
populations appear to be good.
development.
Trout may be threatened, however, by anticipated
The trout are present because of cooler waters in some reaches.
Development within appropriate controls can increase the temperature of stormwater
runoff, as well as the volume of runoff. Higher temperatures can have both chronic (i.e.,
growth and reproduction) and acute (i.e., lethal) impacts on trout depending on the
magnitude of the increase.
The potential negative effects of the nutrients and pollutants discussed above can be reduced
with better management of land use practices within watersheds, understanding our water
resources, and enforcement of stricter rules on runoff and erosion associated with the various
land uses including urban, construction sites, and agriculture.
Several federally mandated
programs are in place to help regulate surface waters, including TMDLs and the NPDES Phase II
program. These programs are discussed in more detail in the following sections and in Section 4.
III.
Lakes and Streams with Water Management Concerns
The following list is a summary of the CAC and TAC input on specific water problems located
wholly or partially in the unincorporated areas of the County that those entities viewed as
concerns in the Scott WMO. Reasons for the CAC and TAC concern are listed with the specific
water body.
Minnesota River (From LeSueur County border to Jackson Township border with Shakopee):
Maintenance of wetlands and nutrient and pesticide loading locally upstream.
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Markley Lake: Flooding; landlocked basin (no outlet); flooding after ordinary high water
establishment.
Sand Creek: Flooding; erosion of banks; agricultural runoff; lack of buffer; more consistent
monitoring; urbanization; change in land uses.
Credit River: Urban runoff; wetland destruction; erosion of banks; flooding.
O’Dowd & Thole Lakes: Erosion of shoreline; residential lawn runoff; lakeshore vegetation;
lack of buffers.
Cedar Lake: Development; agricultural runoff; urban pollution and residential lawn runoff;
faulty ISTS; lakeshore erosion; lakeshore vegetation; lack of buffers.
From the CAC and TAC surveys, water
bodies
listed
in
Table
3.1
were
designated as priority water bodies by
the CAC. Please refer to Appendix E,
Lake Water Quality Report, of the Scott
WMO Comprehensive Water Resources
Table 3.1: CAC Priority Water Bodies
High Priority
Cedar Lake
Markley Lake
O’Dowd Lake
Thole/Schneider Lake
Credit River
Minnesota River
Sand Creek
Medium Priority
Cleary Lake
Cynthia Lake
Geis Lake
Kane Lake
Lennon Lake
McMahon Lake
Murphy Lake
Pleasant Lake
Plan (May 2004) for further information
on these water bodies.
The Vermillion River in Scott County is also a concern for both the VRWJPO and Scott County.
The Vermillion River Watershed Plan identified the following primary issues:
•
River flow volumes have increased
•
Surface water quality is threatened or impaired
•
Vermillion River channel/corridor is impacted and sensitive to change
•
Groundwater quality is threatened or impaired
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•
Additional development is expected
•
Data for making informed decisions is limited
•
Public awareness about water resources in the watershed and appropriate stewardship is
limited
IV.
Wetland Management Concerns
Wetlands are important to the health of Scott County, helping to protect water quality by filtering
pollutants and providing habitat for a diversity of species. Wetlands are the most biologically
productive ecosystem in nature, anchoring food webs through photosynthesis and production of
innumerable small organisms upon which larger creatures depend. In addition, wetlands provide
other functions important to communities, including the slowing and storage of flood water,
cleansing water of certain pollutants, recharging groundwater and serving as an outlet for
groundwater to recharge streams and providing recreational areas.
In their natural state,
wetlands help minimize the need for costly stormwater facilities and flood protection measures.
Although the current regulatory system is more protective than it has ever been, wetlands
continue to suffer from harmful activities associated with growth and development. These
actions include increased stormwater runoff from nearby development, sedimentation from
clearing and grading activities, littering, invasion by exotic plants and animals, and general lack
of good stewardship.
Wetland protection continues to be complex, as new issues of water quality and quantity in
wetlands arise, and fundamental tasks such as consistent definitions and delineation manuals
remain. Growth and development continue to demand the conversion of natural landscapes for
buildings, parking lots, and other uses, making the preservation of wetlands a challenging task.
Solutions to these problems include:
ƒ
acquire and improve data on locations and functions/values of wetlands,
ƒ
increased regulation of activities that occur near wetlands and affect wetlands,
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ƒ
improved implementation and enforcement of erosion control plans,
ƒ
participation in agricultural management practices,
ƒ
noxious weed/invasive species control programs,
ƒ
improved enforcement of regulatory programs that use fines and penalties as
disincentives,
ƒ
improved mitigation through better planning and monitoring of mitigation projects,
ƒ
improved wetland education programs, and
ƒ
increased restoration of damaged wetlands.
Wetland functions and values are a measurement of the benefits that wetland basins provide to
an area, and are the reason for protecting wetlands against damage and destruction. “Function”
refers to the beneficial roles served by wetlands, which include floodwater control and storage,
attenuation of runoff; sediment trapping, water quality enhancement by removal of pollutants;
groundwater recharge, critical fish and wildlife habitat, areas for scientific study and education,
and recreation. Wetland value refers to the public’s value placed on a specific wetland and
includes the social, economic, aesthetic, or ecological benefits that wetland systems provides to
the general population.
Wetland alterations are regulated by several agencies at the federal, state and local levels. The
major agencies involved in Scott County wetland issues include the U.S. Army Corps of
Engineers, the Minnesota Department of Natural Resources, the Board of Water and Soil
Resources, the Soil and Water Conservation District and designated LGUs. General wetland
permitting and/or oversight responsibilities are listed below.
It should be noted that the
permitting requirements at all levels can be complex and assistance is strongly advised from the
County or SWCD before undertaking any work in or near wetland areas.
U.S. Army Corps Of Engineers (COE): The COE requires a permit if a landowner intends to
discharge fill or dredged material into a wetland.
Minnesota Department of Natural Resources (MnDNR): All public water and wetlands below the
Ordinary High Water Level (OHWL) are considered protected waters by the MnDNR. Any
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project that alters the course, current, or cross-section of a protected water or wetland is subject
to the regulatory jurisdiction of the MnDNR.
Board of Water and Soil Resources (BWSR): Primary overall administrator (at the State level) of
the Wetland Conservation Act (WCA) for the State. Provides staff for technical support to the
County.
Soil and Water Conservation District (SWCD): In Scott County the SWCD has been designated
as the technical resource for WCA by the County as well as other LGUs.
Local Government Units (LGUs): Currently there are 11 LGUs (10 Townships) in
unincorporated Scott County. The LGU authority was obtained by each LGU passing a
resolution to administer the WCA.
All the townships in Scott County passed resolutions
accepting this responsibility. One township, Sand Creek, has since passed the WCA authority to
the Scott WMO. Each LGU has the primary responsibility for administration of the WCA within
its jurisdiction. It is anticipated that the Townships will continue to serve as the LGU for WCA
permitting into the future unless the authority is transferred to the Scott WMO. The WMO has
offered in the past to accept the LGU authority for all of the Townships.
MnDNR conservation officers and other peace officers may issue cease and desist, restoration,
and replacement orders for violations of the WCA. A violation of an order is a misdemeanor.
The County Attorney pursues criminal prosecution of violations under the WCA.
Civil
enforcement is also an option for obtaining compliance with the WCA.
V.
Impacts of Stormwater Discharges and Runoff
Untreated stormwater from both urban and agricultural land can have a significant impact on
water bodies through erosion, temperature increases, and nutrient loading.
Pollutants in
stormwater can include sediments, nutrients, bacteria, increased temperature, oils, grease, metals,
and other toxicants. These contaminants can harm biological populations, destroy fish and
wildlife habitat, restrict swimming, and contaminate sediments. Sources include runoff from
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motor vehicles, fertilizers, pesticides and herbicides; runoff from urban development;
construction sites; commercial and industrial development; pet feces; and inadequate
management of other wastes. Areas developed prior to the general adoption of the Metropolitan
Council’s Interim Strategy and the adoption of the updated Scott County Zoning Ordinance and
Comprehensive Plan (May 2001) may still be routing stormwater directly into ditches or into
nearby water bodies.
Of the 11 lakes located wholly or partially within Scott County that are included in the MPCA
Lake Water Quality Database, 6 lakes showed high trophic conditions. A trophic state of 60 or
above shows a dominance of blue-green algae, algal blooms, and extensive macrophyte
problems. These lakes are eutrophic or hyperutrophic, and do not support, or only partially
support, swimming. Appendix E of the Scott WMO’s Comprehensive Water Resources Plan
(May 2004) contains additional information about trophic states and data for each lake.
The following lakes within the Scott WMO have trophic states above 60: Cedar (71); Cynthia
(76); McMahon (69); O’Dowd (66); Pleasant (73); and Thole/Schneider (70).
Those lakes with trophic states below 60, which is the expected trophic state for this ecoregion,
are Cleary (55); Crystal (55); Markley (58); Murphy (46); and an unnamed lake (45). The
unnamed lake is designated #70-11 in SE ¼ of Section 10 in Credit River Township – bordering
Dakota County/City of Lakeville.
Nutrient loading from stormwater in Scott County is an issue as evidenced by the proposed
TMDL list for impaired waters in the County, which shows many of the waters listed for
nutrients and turbidity. Clearly identified minimum baseline parameters, monitoring of direct
discharges of stormwater, and improved maintenance of stormwater ponds and systems could
help protect the County’s water bodies from excessive nutrient loading and heavy sedimentation.
In addition, the County will be using incorporation of low impact design techniques, reduction of
impervious areas, and development of a regional ponding system to help improve the quality and
reduce the quantity of stormwater.
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Increases in the temperature are potentially an issue for the Vermillion River watershed portion
of the County. Portion of the Vermillion River are a designated trout stream. The designated
areas are all in Dakota County, but Scott County portions represent the headwaters of the river
and discharge to the trout waters. Larger volumes of warmer flow from Scott County could
affect the trout reaches.
In September of 2000, Barr Engineering prepared the Scott County Stormwater Impact Study, as
a part of the County’s development moratorium work plan in order to help evaluate the public’s
costs for stormwater management created by new development. The study used computer
models to evaluate two hypothetical watersheds with conditions typically found in the
developing areas of the County. The results show that most rural residential development
appears to have only minimal hydrologic impacts, even in comparison to agricultural uses. In
addition the model results showed that commercial and industrial development, as well as
agriculture and clustered residential with agriculture, had the highest hydrologic impacts. The
study also helped determine general water management planning and administration costs
associated with stormwater impacts from new development. Currently a portion of these costs is
offset by the fee for stormwater planning and water quality, as specified in the Fee Schedule for
the Scott County Zoning Ordinance No. 3.
Issues associated with water quality and quantity have the potential to be exacerbated by the
changing land use in the County, which was listed as the 12th fastest growing county in the U.S.
in 2002 by the U.S. Census. In 2003, Scott County was named the 8th fastest growing county in
the U.S. Urban development has potential to have profound influence on the quality of water.
Development dramatically alters the local hydrologic cycle. The hydrology of a site changes
during the initial clearing and grading that occur during construction. Trees, meadow grasses,
and, to a lesser extent, agricultural crops that had intercepted and utilized rainfall are removed
and natural depressions that had temporarily ponded water are graded to a uniform slope.
Cleared and graded sites erode, often are severely compacted, and can no longer prevent rainfall
from being rapidly converted into runoff. After construction of roof tops, roads, parking lots,
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driveways and other impervious surfaces rainfall is no longer able to infiltrate into the soil.
Consequently, most rainfall is converted directly to stormwater runoff. For example, a one acre
parking lot can produce 16 times more stormwater runoff than a one acre of meadow each year
(Schueler, 1994).
The increase in stormwater runoff rate and volume from development can challenge the existing
natural drainage systems to handle runoff in an effective, environmentally sound, and long-term
manner. Many times the natural drainage system is often “improved” to rapidly collect runoff
and quickly convey it away (using curb and gutter, enclosed storm sewers, and lined channels).
The stormwater runoff is subsequently discharged to downstream waters such as streams, rivers,
lakes, or wetlands where problems are created due to causing an imbalance or overloading of the
natural conveyance system. This leads to additional downcutting and deterioration of the natural
channel, which results in increased erosion and an unstable water conveyance system.
Careful management of stormwater rates and volumes will be essential over time, as well as
methods to attain better water quality associated with the County’s water resources.
VI.
Flooding and Stormwater Rate Control
The MnDNR oversees the local administration of the state Floodplain Management Program
(MN Statutes 103F.101-103F.165 and MN Rules 6120.5000 – 6120.6200) by promoting and
ensuring sound land use development in floodplain areas in order to promote health and safety of
the public, minimize loss of life, and reduce economic losses caused by flood damages. Federal
floodplain management oversight has been delegated to the MnDNR by the FEMA. However,
FEMA still has a significant impact on local floodplain regulation through its role in publishing
local floodplain maps and administering the NFIP.
The natural floodplain is an important part of the surface water system. It affects storm runoff,
water quality, vegetative diversity, wildlife habitat, and aesthetic qualities of rivers and lakes.
Therefore, any alteration of the floodplain should be carefully evaluated. Generally, the least
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amount of alteration to the natural system is usually the most ecologically and hydrologically
sound development decision.
Figure 3.1 Floodplain Areas (MnDNR)
As defined by the MnDNR on their
Division
of
Waters
“Floodplain
Management” Web site, the floodplain
is considered to be the land adjoining
lakes and rivers that is covered by the
100-year or regional flood, as shown in
Figure 3.1. This flood is considered to
be the flood that has a one percent
chance of occurring in any given year.
Using sophisticated engineering techniques, it is possible to calculate the magnitude of such a
flood along those rivers where long term flood records have been kept. Various government
agencies conduct these studies, and as they become available, local communities are required by
state and federal law to adopt floodplain zoning ordinances.
The floodway is the land immediately adjoining the river channel that is the natural conduit for
flood waters. The floodway must remain open in order to allow flood waters to pass. When the
floodway is obstructed by buildings, structures, or debris, flood water will be dammed up and
will flood even larger areas upstream. Large portions of the floodplain store and later release
flood waters, which reduce river flood stages.
Development of these areas can result in
increased flooding. Under the statewide floodplain management standards, local communities
cannot allow development in the floodplain that would cumulatively cause more that a ½-foot
increase in the height of the 100-year flood. Since this area must be left open to pass flood
waters, only open space uses, such as farm land, residential yards or gardens, golf courses, parks,
playgrounds, or parking areas, are normally allowed in the floodway.
The Flood Fringe is the remainder of the floodplain lying outside of the floodway. This area is
generally covered by shallow, slow-moving floodwaters. Development is normally allowed in
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the flood fringe provided that all structures are placed on fill so that the lowest floor, including
the basement, is at or above the regulatory flood level An engineer or surveyor will need to
evaluate the proposed building site and determine the property’s flood protection elevation and
whether the proposed building is in the floodway. Map 11 shows FEMA’s currently published
data for 100-year floodplains in Scott County. The County is currently working with FEMA to
complete updated Digital Flood Insurance Rate Maps for the County.
The Regulatory Flood Protection Elevation (RFPE) refers to an elevation 1 foot above the
100-year flood. The elevation of the lowest floor of a structure must be at or above the RFPE.
An access road elevation must be within 2 feet of the flood protection elevation. Scott County
Zoning Ordinance No. 3 provides detailed, local requirements in addition to these state-required
regulations.
The economic impact associated with flooding, which includes damage to homes, structures, and
other property, can be devastating to the public both in personal loss and in insurance costs. The
MnDNR also lists the following:
ƒ
Larger flood peaks and longer flood durations result in longer periods of time that
recreational facilities are not available for use.
ƒ
Flooding damages or destroys recreational trails and bridges.
ƒ
Repair of flood-damaged facilities and controlling public use of facilities during flooding
events places more strain on budgets and personnel.
ƒ
Inundation of upland habitats for longer time periods also alters the mix of plant and
wildlife species present.
When a watershed becomes wholly or partially occupied by development, the development has
the potential to increase the volumes and rates of runoff from stormwater dramatically. The
increase in paved ground surfaces, together with the installation of a more efficient drainage
system, greatly reduces surface depression and detention storage, reduces the time of
concentration and delivers runoff to the nearest watercourse in a fraction of the time that this
would have taken prior to development. The result is a much sharper rise in the rate of flood
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runoff, which greatly increases the peak discharge rate from the watershed and substantially
increases the subsequent depth and severity of flooding.
With the rapid development currently occurring in the County, an increase in impervious area is
expected.
This emphasizes the importance of stricter regulations on management and/or
approval of impervious areas within areas of development or re-development.
Innovative
landscape design such as the incorporation of open space, pervious pavement, or low-impact
development techniques can substantially lessen the impervious surface, or the impacts of
impervious surfaces, throughout new development, both residential and commercial.
Scott
County will encourage the use of natural infiltration and natural retention facilities for
stormwater, which is consistent with the County’s GWPP, local stormwater management plans,
regional standards, and state guidelines.
Well-designed stormwater conveyance systems may enhance groundwater supplies and soil
moisture levels as well as augment landscape amenities and protect existing surface water
resources.
Recharging groundwater through the infiltration of stormwater rather than
encouraging conveyance of stormwater off site can help to minimize flooding and rate control
issues. Inter-community cooperation and collaboration is necessary for effective control of
stormwater and important for improved educational initiatives and outreach activities (for
developers, builders, city and township officials, etc.).
One of the issues the County is facing is flooding around landlocked basins (lakes, ponds and
wetlands that, under normal hydrologic conditions, do not have a surface overflow). Landlocked
basins are difficult to manage because water leaves the basin only via groundwater and
evaporation. These are very slow processes for dissipating runoff. As long-term weather
patterns fluctuate, the lakes often have wide fluctuations in water level. Routine engineering
methods often do not adequately predict these fluctuations.
In consequence, it is often
discovered that homes, roads and other improvements have been built within the floodplain of
landlocked basins. This often results in pressures to construct engineered outlets, which are
expensive and may add runoff volume and nutrients to downstream water bodies.
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A complete inventory of landlocked basins in the County has not been completed; There is no
current list of lakes that do not have outlets in Scott County. It is the intention of the County’s
Natural Resource Department to work with the SWCD and MnDNR to compose a list of
landlocked lakes and provide this information on the County’s GIS. The County will use the
information to assist the WMO with its assessment of stormwater and flooding issues.
In Chapter 6 of the zoning ordinance, the County has adopted (6B-2q) a requirement that the
100-year flood level be determined using the runoff from the 100-year wet year, which should
set more conservative flood levels. The same ordinance (6B-1e-2a) requires that added runoff
volume from new developments is not allowed unless the applicant can demonstrate that the
added volumes will not adversely affect downstream properties. This evaluation requires review
of any downstream landlocked lakes or ponds. These stricter stormwater management standards
will help limit future flooding problems around landlocked lakes in the townships.
Lakes in Scott County that have outlets are: Cedar, Clark, Cleary, Cynthia, Hickey, Pleasant, and
St. Catherine.
VII.
Impacts of Soil Erosion
The most important pollutant to control in all areas of the County is sediment. Sediment settles
in water bodies, carries some types of pesticides and nutrients, and clogs drainage systems. If
erosion is reduced, the sediment found in runoff along with the associated nutrients and
pesticides will be reduced. The County established an erosion control enforcement program,
starting in 2005, which incorporates the County’s erosion control requirements, as well as the
WMO and State standards. The program includes inspection, tracking, and enforcement of
projects permitted throughout the unincorporated areas of the County. Inspectors also respond to
unpermitted land disturbances which may be causing soil erosion and sedimentation.
Urban land uses:
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Areas of Scott County have experienced rapid growth in the past few years. Developers and
builders are required to prepare erosion control plans, but historically they have not maintained
erosion control and sediment measures throughout construction of the project. This leads to
increased sedimentation in lakes, streams, and wetlands. The newly implemented Erosion and
Sediment Control Program has increased enforcement of the erosion control regulations.
Agricultural land uses:
According to the “1997 Census of Agriculture” (NASS, 1999), there were 805 farms in Scott
County, covering approximately 118,000 acres or approximately 50% of land in Scott County,
with an average of 146 acres per farm. Of the 99,795 acres of cropland in Scott County,
approximately half are adequately treated with proper conservation practices, according to Scott
SWCD.
One conservation practice that is recommended by the SWCD and USDA is leaving crop residue
on the fields to help protect the soil surface during periods when no vegetative cover is present.
Residue surveys are conducted each spring in Scott County and in counties across the state. Data
can be presented in several different ways and Figure 3.2 shows corn-soybean survey results for
Scott County from 1995 through 2001 (USDA, 2002). It should be noted that the percentages in
Figure 3.2 represent fields meeting residue targets (>30%) plus fields with greater than 15
percent residue when following soybeans. Scott County ranked 12th in the state for percentage of
fields meeting residue targets during 2001.
70%
60%
1995
50%
1996
40%
1997
30%
1998
20%
1999
2000
10%
2001
0%
Crop Residue Percentage
Figure 3.2 Corn-soybean residue survey results
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Crop residue data for Scott County can also be shown as percent of fields (by year) with residue
cover by crop type. Figures 3.3 provides this comparison for corn, soybeans and small grains
for the years 1995 through 2002 (BWSR, 2002).
Figures 3.3 Corn, soybean and
small grain residue
Percent of Fields with Crop Residue
16 to 30%
Percent of Fields with Crop Residue
0 to 15%
100
90
80
70
60
50
40
30
20
10
0
Corn
Soybeans
Small Grains
1995 1996 1997 1998 1999 2000 2001 2002
Year
100
90
80
70
60
50
40
30
20
10
0
Corn
Soybeans
Small Grains
1995 1996 1997 1998 1999 2000 2001 2002
Percent of Fields with Crop Residue
>30%
100
90
80
70
60
50
40
30
20
10
0
Year
Corn
Soybeans
Small Grains
1995 1996 1997 1998 1999 2000 2001 2002
Year
Scott SWCD has identified high priority cropland erosion areas, but cropland in all areas of the
County is subject to wind and water erosion.
Issues related to cropland erosion can be
categorized as follows: 1) sheet and rill erosion, 2) wind erosion, and 3) gully erosion. Many of
the erosion control practices are temporary in nature and can be removed or discontinued easily.
The loss of erosion control practices on land that needs continued protection is an on-going
concern, especially when considering that prime farmland and other farmland of importance is
being converted to other uses and, therefore, being removed from commercial agricultural
production. Consequently, further protection of highly erodible lands is necessary.
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Buffers:
Buffers are transitional areas between two different land uses that help mitigate the effects of one
land use on another. Buffers can take different forms and are designed for various functions.
For example, filter strips are primarily used to increase infiltration of surface runoff and provide
for sediment trapping while shade strips can be used to provide shading to waters sensitive to
temperature, such as trout streams.
Buffer strips are needed along water bodies to alleviate impacts to water resources. Issues
include grazing along stream banks and shoreline, farming along ditches or to the edge of water
bodies, and the replacement of native vegetation with manicured lawns, which leads to increases
in erosion and decreases in infiltration (pollution of surface water).
VIII. Impact of Land Use Practices
With the current levels of development and existing degradation in some water bodies, it is
necessary to improve the levels of water quality. Point sources of pollution are regulated and
monitored by the State. Non-point source pollution remains an issue throughout the County,
with each water body affected to some degree and in some manner by its surrounding land use
practices. Water quantity is critically linked to water quality. Controlling water quantity and
sedimentation are particularly important, since those processes contribute to flooding and nonpoint source pollution, which in turn causes physical damage.
Historically the majority of regulatory focus was on point sources of water quality degredation,
or known sources of pollutant discharge. Therefore, water quality standards have been based on
chemical components rather than ecosystem requirements. With non-point source water quality
issues becoming more of a concern, integrating the state regulatory programs with local water
planning requirements and involving local and tribal governments in the process of determining
water quality goals and priorities is essential. A watershed approach is needed to address nonpoint source pollution and all stakeholders will need to work together to understand, study, and
ultimately manage solutions to non-point water quality issues.
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Land use directly affects the quantity and quality of water resources. Scott County intends to
apply principles of land use and landscape design to minimize stormwater runoff and maximize
water quality. Specific land uses that are the greatest contributors to the degradation of water
quality include:
•
Urbanization of large land areas
•
Noncompliance with erosion and sediment control plans
•
Excessive pesticide, herbicide, and fertilizer application
•
Confined animal feedlot operations
•
Nonconforming ISTS
•
Wetland alterations (drain or fill activities)
•
Intensive conventional row crop agricultural practices
•
Poorly managed open surface tile inlets
•
Industrial buildings and parking lots
The percentage of impervious land in an area is one indicator of the potential affects on the
quantity and quality of water in an area. Impervious land does not allow water to infiltrate into
the soil. Instead, water becomes runoff, carrying with it pesticides from lawns and fields, and
sediment from eroded areas. Generally, the more impervious land in a development, the higher
the quantity of runoff water and the lower the quality of water discharging from that area if the
runoff is not managed appropriately. In terms of the rapid growth of the County, impervious
land in developments needs to be limited, and construction site erosion control needs to be
strictly enforced. In the agricultural areas of the County, farming practices need to reduce the
amount of sediment and nutrients in runoff from fields, and farm operators need to be aware of
and participate in programs designed to reduce runoff.
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IX.
Section 3, Page 75
Impacts of Water Quality and Quantity Management Practices
Heavy sedimentation and nutrient loading of the County’s lakes, streams, or wetlands can greatly
impact the natural habitat around the water bodies, the health of the water bodies themselves,
their aesthetics, and the overall health of the communities surrounding the water resources. In
addition, nutrient loading and heavy sedimentation of the water resources can reduce or eliminate
the more desirable wildlife of lakes such as fish, small animals, amphibians, and birds. This can
lead to a less diverse habitat and reduce the capacity of the water body for fishing, hunting, bird
watching, and education. Heavy algal growth or algal blooms can reduce a lake’s recreational
use for contact activities such as swimming and boating.
Stormwater runoff that is directed into the soil without adequate treatment can also degrade
groundwater quality. Certain land uses and activities are known to produce higher loads of
metals and toxic chemicals. Pollutants, such as chloride, nitrate, copper, dissolved solids and
some polycyclic aromatic hydrocarbons (PAH’s) can migrate into groundwater and potentially
contaminate wells. Contaminated lakes and streams also have the potential of leaching toxins
into the groundwater and causing health problems in the larger community.
Fertilizer and pesticide use in agriculture is also an area of concern. As farming practices and
crop rotations have changed in the past 30 years, the increased use of pesticides and commercial
fertilizers has been a mixed blessing. On the positive side, it has improved farm productivity.
On the negative side, it has added to the potential for low level groundwater contamination in
certain vulnerable aquifers in Minnesota. Areas susceptible to groundwater contamination in
Scott County are shown in Map 5. In addition, surface waters become eutrophic when nutrient
levels become too high – causing harm to vulnerable plant and wildlife species.
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With the advent of anhydrous ammonia in the early 1960’s, nitrogen fertilizers became
inexpensive, which resulted in increased usage.
Nitrogen, if over-applied or applied at
inappropriate time, can easily leach to the groundwater. Phosphorus was also inexpensive,
which led to greater farm and non-farm usage.
Runoff high in phosphorus has caused
accelerated euthrophication in lakes. These potential problems are not necessarily caused by the
simple increase in the use of fertilizers and pesticides over the years, but primarily from poor
application and management methods.
X.
Impacts on Groundwater
Scott County provides for the protection of groundwater in accordance with MN Statutes
103B.255 through its approved and adopted GWPP. The GWPP is incorporated by reference
into the Scott County Water Resources Plan and provides for implementation of the GWPP’s
implementation objectives.
Scott County relies on groundwater for its domestic, municipal, and industrial supplies. The
percentages of reported groundwater usage in the County are in some cases much higher than
statewide percentages. The large difference in groundwater usage is due to the amount of
urbanization occurring in Scott County as compared to the rest of the state. These urbanizing
areas rely exclusively on groundwater for their municipal and private water supply. Therefore,
they are particularly vulnerable to aquifer contamination and groundwater table drawdown.
Groundwater is located beneath the earth’s surface in soil and geologic materials. Beneath the
water table, all soils and geologic materials are saturated with groundwater, which is stored in
and flows through an intricate network of pores, joints, fractures and solution cavities in the
underground geologic formations. Figure 3.4 shows how groundwater flows from recharge to
discharge areas.
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As indicated in the above figure, groundwater recharge and quality are affected by infiltration
rates. Slow infiltration of rainfall through the soil layer is essential for replenishment. The
amount of rainfall that recharges groundwater varies, depending on the slope, soil, and
vegetation. Because development creates impervious surfaces that prevent natural recharge, a
net decrease in groundwater recharge rates can be expected in urban watersheds. Thus, during
prolonged periods of dry weather, stream flow sharply diminishes due to fewer groundwater
inputs from the surface (especially in the case of a “gaining” stream).
Excessive pumping and dewatering also affects aquifer levels, particularly within the low-lying
Minnesota River valley area of the County and the areas that are highly susceptible to
groundwater contamination. Large fluctuations in groundwater levels due to excessive pumping,
along with increased impervious areas can lead to issues of falling groundwater levels and effects
on private wells in the County. During the dry summer of 2001 there were numerous issues with
private well owners due to falling groundwater table levels in Credit River Township.
As development in Scott County continues, conservation is undoubtedly the easiest way to
reduce the pressures on the groundwater supply and avoid restrictive groundwater use controls.
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Proactive conservation works on the assumption that by cutting out wasteful practices there will
be more water available in the future. Benefits of this type of conservation philosophy identified
by the Metropolitan Council (1992) include:
ƒ
Preservation of the resource to ensure that water supplies will be available in the future.
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Elimination or postponement of new source development with associated saving of
capital investment, operating costs, and energy.
ƒ
Improvement of water supply efficiency to maximize the use of the resource.
ƒ
Institutionalization of conservation practices that help utilities cope with short-term water
shortage emergencies.
Conservation can also be treated as reactive. Reactive conservation results from water shortage
emergencies and tends to be regulatory. If a water supply crisis exists, communities can enact
sprinkling bans, rationing, and other controls on non-essential uses to assure that drinking water
supplies are maintained. Communities that take a proactive approach to water conservation may
be able to prevent these water shortages before options are narrowed.
In addition to groundwater supply issues, groundwater contamination is of concern in the
County. In the GWPP, a variety of sources of groundwater contamination are given including:
Feedlots:
Historically the major concern regarding feedlots has been surface water pollution caused by
runoff waters.
Further study of this issue has shown that leaching of feedlot waste into
groundwater is also a concern. Without proper management, feedlots can be a major source of
nitrogen, phosphorus, and organic pollution to both surface and groundwater. Feedlots located in
close proximity to a well can cause contamination of the aquifer, which in addition to
contaminating the first well, can contaminate other wells using the aquifer for a water supply.
Additionally, this pollution can enter the groundwater through sinkholes, cracks and fissures
common in areas with a high potential for fractured bedrock.
Landfills:
Improper site selection and use of improper materials to cover the waste has contributed to
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groundwater contamination. Industrial landfills contain many organic compounds, toxic metals,
and other inorganic contaminants that are difficult to clean up once they have entered the
groundwater system.
Mining Operations:
Sand and gravel mines often extend into buried drift aquifers; once the surface soils and
vegetation are stripped away, contaminants can flow into the groundwater with little obstruction
(trapping or filtration by vegetation and soil materials).
Individual Sewage Treatment Systems (ISTS):
Non-compliant ISTS may be located too close to the groundwater table (less than two feet) for
adequate sewage treatment through percolation in the soil, or they may be failing and potentially
contaminating the groundwater due to overloading or lack of maintenance. It is difficult to
monitor ISTS that are failing beneath the surface and leaching into groundwater.
Stormwater Ponds:
Issues associated with stormwater runoff include potential water quality degradation that can
cause the contamination of groundwater supplies.
Aggravating conditions include unlined
treatment ponds that are designed for protection of surface waters that fail to consider potential
impacts to groundwater.
Wells:
Improperly constructed, operated, or abandoned wells can directly introduce pollutants into
individual water supplies and the aquifer(s) through which these wells constructed. Excessive
pumping from wells can also cause water to be drawn into a well from larger distances around
the well. If contaminated groundwater is present within this expanded circumference, it may
result in contamination of the well.
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Underground Storage Tanks (UST):
USTs are of concern because leaking tanks allow contaminants to infiltrate into the surrounding
soils and eventually groundwater.
Depending on the circumstances, leaking USTs can go
unnoticed for several years.
Groundwater Quantity:
Programs and policies from the GWPP are updated and implemented through this Water
Resources Plan.
Future issues may occur with increasing development.
The County, in
conjunction with its urban and developing areas, will need to further develop wellhead protection
areas (WHPA) to gain a better understanding of where major recharge areas are located and
protect the more vital aquifer areas. Water conservation is needed to prevent shortages and
reduce the amount of sewage treatment. Monitoring of groundwater levels and quality is also
needed to better understand the condition of the current water supply. Contamination of the
groundwater supply is difficult to monitor and expensive to repair, and the County will take a
leadership role to help determine preventive measures to protect this essential resource.
The County will also encourage interconnections between water supply systems to enhance
water supply management between communities. Interconnections in municipal water supply
systems could potentially help to mitigate emergency situations by providing an alternate water
source should a well become contaminated or run dry.
XI.
Adequacy of Protection for Surface Water Resources
Initiatives such as the EPA’s TMDLs, which is a program administered by the MPCA, as well as
the NPDES Phase II program are aimed at managing surface water better. In addition, the WCA,
MnDNR Shoreland rules, MnDNR Protected Waters Rules, and other federal, state and local
regulations have made dramatic progress in the protection of wetlands and reducing adverse
impacts on water quality.
A focus of the wetland goals and objectives in this Plan is to work with the WMO to develop a
Comprehensive Wetland Management program, and included in that is the protection and
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management of uplands and natural corridors between wetlands. The pressure to drain or fill
wetlands and to develop upland areas or important natural areas will parallel development
pressures in the County. Implementing wetland policies and programs to protect, restore and
connect existing wetlands will provide future savings in the areas of flood control, water quality
and wildlife health. The County must work with the WMO to identify and prioritize the rare,
unique and otherwise high quality wetlands and subsequently implement special protection
measures as an investment in the overall environment. The County will also work with the
Townships who retain the WCA LGU authority to ensure that the Comprehensive Wetland
Management Plan’s policies and programs are met.
This document identifies and prioritizes lakes and streams (in terms of both TMDLs and the
findings of the Citizens Advisory Committee) and outlines an approach for the development of a
Comprehensive Wetland Management Plan, including establishing a framework to develop a
functions and values assessment for wetlands in the County.
Existing regulations can only partially address the surface water issues affecting the County.
New regulations without adequate enforcement, funding, and education in the County will not
sufficiently protect the County’s water resources. Mechanisms for the study and assessment of
water resources, education initiatives, adequate funding, and an enforcement plan need to be in
place before adverse impacts from land use practices on water resources and their ultimate
management and protection in the WMO and County can be satisfactorily addressed.
XII.
Adequacy of Existing Management of Stormwater, Flooding and
Soil Erosion
Numerous programs affect how water and related resources are managed in Scott County. The
implementation of this Plan will seek funds from a variety of sources for program development
and management priorities. Although existing management provides an adequate basis for most
practices, limited staff and resources often restrict the effectiveness of these programs.
Controls in Scott County
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Goals, policies, and standards in this Water Plan augment existing ordinances and programs to
control erosion in the unincorporated areas of the County. The existing ordinances include the
general criteria in practices contained in Protecting Water Quality in Urban Areas (PCA, 2000),
the Minnesota Construction Site Erosion and Sediment Control Handbook (BWSR, 1988), and
the new Minnesota Stormwater Manual (MPCA, 2005).
The NPDES program, administered by the MPCA with the assistance of local communities, was
published in the Federal Register on December 8, 1999. The NPDES Phase II program involves
several communities within Scott County that are considered to be in an “Urbanized Area” by
the EPA and were thus mandated to comply with the NPDES Phase II MS4 permit requirements.
Communities mandated by EPA to provide a Notice of Intent and a Storm Water Pollution
Prevention Plan (SWPPP) by March 10, 2003 included Scott County along with Louisville,
Jackson, Credit River, and Spring Lake Townships. These communities must implement their
SWPPPs by the end of the first permit term (5 years).
The NPDES Phase II local stormwater management programs will need to address several areas
including a Best Management Practice (BMP) approach to stormwater management, construction
site stormwater runoff control, post construction stormwater management, public education and
public involvement. The programs will also be responsible for establishing measurable goals,
methods in which to meet those goals, and measures to track performance and progress.
The TMDL program, also administered by the MPCA provided a list of impaired waters to the
EPA in the fall of 2002, which was approved by the EPA in January 2003. The list was updated
and approved by the EPA in May 2004. A draft list for 2006 is currently available for public
review, but has not been adopted by the MPCA. The list includes several water bodies within
Scott County. Timelines for developing the specific TMDL for each water body are included as
part of the list. Development of the TMDLs will require studying/modeling specific watersheds
to provide a management plan that will address the pollutant(s) that the water bodies are listed
for.
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Controls such as those listed above are necessary to prevent degradation of water quality within
the County associated with erosion and runoff issues. Scott County also supports the efforts of
the SWCD to encourage farmers to implement practices that protect topsoil and reduce
agricultural erosion. The County erosion control goals are consistent with long standing national
programs to protect topsoil and reduce the amount of sediment reaching sensitive water bodies
such as the Minnesota River.
The MPCA is the state authority in enforcing rules (Minnesota Rules 7020) for feedlots.
However, it does not have sufficient staff and resources to assure state-wide compliance and has
a delegation program where individual counties can accept responsibility for administering most
of the feedlot program within their respective county. Scott County obtained delegation from
MPCA to uniformly administer 7020 within the County as of January 2002. The Natural
Resources Manager for the County has been designated as the County Feedlot Officer, with the
SWCD continuing to provide the technical assistance to landowners.
Education
Education is an important and essential component of this Plan. While there are currently
educational activities in place managed by the County, the goal of this Plan is to expand the
educational program associated with water resources and to provide opportunities for public
participation in achieving the goals and objectives within this Plan. Current programs include:
•
Periodic articles on water resource management in the County newsletter (The Scene),
published 6 times a year, mailed directly to all Scott County residents.
•
Water pollution prevention tips in newsletters are sent out to all Scott County residents as
part of the County’s solid waste program.
•
The County works with the Scott SWCD to promote urban erosion control practices with
developers and builders and agricultural best management practices with rural agricultural
producers in the County. Brochures and fact sheets on various practices, BMPs, etc are
available for free through the SWCD office.
•
Scott County’s University of Minnesota Extension Service promotes agricultural and
residential practices that prevent or reduce pollution, including ISTS.
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•
Section 3, Page 84
The Natural Resources County website provides information on water resources (to be
updated and expanded with the adoption of this Plan).
•
There are a few school programs in place, more will be added.
•
Several non-profit organizations provide education and opportunities for public participation
in water programs.
•
Erosion Control Workshops are held at the County to educate homeowners, builders,
developers, contractors, etc. on the importance of erosion control. The workshops also
illustrate the permitting process
•
Additional educational funding will be needed to address a broader range of water
management issues.
Rural Programs
Scott County, the Scott SWCD, and the County’s U of M Extension Service work directly with
farmers and residents with soil erosion and water quality degradation programs, and maintain
values of natural storage and retention systems, and water level control structures.
Governmental Oversight
Local government’s (County, City, and Township) most effective tool for enforcing erosion
control plans, stormwater management plans, and wetland conservation plans is the platting/plan
review process, through the enforcement of local ordinances.
Local, state, and federal
regulations related to stormwater management, erosion control, open space dedications, wetland
conservation, tree preservation, are addressed when new developments are platted. Developers
are required to follow design specifications and standards once a plat has been officially
approved.
However, during the construction of the development, contractors hired by the
developer may not be aware of plat conditions or are negligent in carrying out the specified
requirements. In addition to direct water quality and quantity impact that may occur if plat
requirements are not followed, secondary impacts such as wetland sedimentation, sheet and gully
erosion, loss of trees due to injury and disease, etc. may occur. LGUs that have adopted a policy
of low tolerance for plat violations of wetlands, erosion control, or tree ordinances indicate that
compliance increases with enforcement oversight. The County needs to continue to be vigilant
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in the enforcement of platting requirements and wetland protection and erosion control
ordinances. Additional training of local officials, developers, and their contractors, as well as
funding may be necessary to provide for additional inspections and enforcement.
Lake and Stream Monitoring
There are over 53 lakes in Scott County (as identified on the MnDNR Protected Waters List,
1987), and numerous rivers, streams, wetlands, and creeks in Scott County. The MPCA and
Metropolitan Council administer lake and watershed outlet monitoring programs, but not all of
the County’s lakes and streams are currently being monitored. The County will assist the WMO
with coordinating citizen monitoring programs for taking simple measurements such as water
clarity to get an awareness of the condition of the surface water.
The Citizen Lake Monitoring Program (CLMP) is a cooperative program combining the
technical resources of the MPCA and the volunteer efforts of citizens statewide who collect
water-quality data on their lakes. The program greatly multiplies the MPCAs water-quality
sampling capabilities, while volunteers learn about the water quality of lakes in their region and
the causes and effects of lake pollution. The Metropolitan Council sponsors the Citizen-Assisted
lake-Monitoring Program (CAMP). The purpose of CAMP is to provide lake and watershed
managers with good lake quality data as well as involve interested citizens. Citizen volunteers
collect samples from lake surfaces at bi-weekly intervals from mid-April through mid-October.
Volunteers collect water to be analyzed for total phosphorus, nitrogen and chlorophyll-α, and
measure surface temperature and water transparency.
The MPCA’s CLMP has monitored several lakes in Scott County. The lake clarity data shows a
general decrease in clarity in the late 1980’s and a steady increase in clarity until peaking in the
early 1990’s. In the last several years however, the clarity of the lakes monitored appears to be
decreasing. This information can be helpful in giving a general idea of the water quality of lakes
and showing the effectiveness of current policies. Utilizing the MPCA’s Citizen Stream
Monitoring Program (CSMP) will be a consideration of this Plan, as well as the Metropolitan
Council’s established Citizen Assisted Monitoring Program (CAMP).
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These programs are
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attractive due to their low expense and ability to actively involve and educate the general
community in gathering important data on the County’s water resources.
With the help of volunteers, Scott County will be able to identify water bodies that are in the
greatest need for improved water quality. The County will then be able to direct the necessary
attention and resources, including staff and funding, in an attempt to restore these priority water
bodies to a healthy condition.
County Ditches
County ditch repair and improvements shall comply with statutory requirements. MN Statute
Section 103E.021 requires the establishment and maintenance of 16.5 ft permanent grass buffers
along ditches. Agriculture is prohibited within the buffers. Ditches that were constructed prior to
the enactment of the law stated above may not have an established buffer because there have not
been any improvements or other work performed on the ditch since the law took effect in the
1970s. Past problems will be mitigated when improvements are made to the ditches. Currently
the ditch authority in the County is the County’s Highway Department.
XIII. Adequacy of Capital Improvement Programs
This document provides the first Water Resources Plan for Scott County and as such is the
beginning of a formal CIP directly related to water resources. The Plan will identify projects for
the unincorporated portions of the County. It is the intention of the County to work with other
water authorities in the County in partnership to achieve success on larger endeavors such as
regional ponding.
XIV. Corrective Actions
Corrective actions to address the water management issues described above are contained
throughout Section 3. A summary of these corrective actions is provided below:
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Increased Water Quality Monitoring
The County is proposing to work with the Scott WMO to establish a more comprehensive
approach to monitoring water quality throughout the County. Increased monitoring will allow
the County to further analyze sources of pollutants and develop strategies to minimize further
water degradation.
Comprehensive Wetland Management Plan
The County will work with the Scott WMO in developing a comprehensive wetland management
plan. The comprehensive wetland management plan will include identification of prime wetland
sites, protection policy, preservation programs, restoration requirements, and regulation
guidance.
Land Development Practices
The County will continue to encourage the use of the natural drainage systems as well as a
reduction in new impervious surfaces associated with new development projects. Reducing
impervious surfaces will decrease the volume of surface water runoff from development sites
and increase the potential for groundwater recharge. The County currently offers density
bonuses for open space design to encourage reduced impervious areas. The County will
continue to explore incentive options to encourage smaller areas of new impervious surfaces.
Erosion and Sediment Control Program
The County has implemented an erosion and sediment control (ESC) program for development
projects as well as building permits. The program consists of weekly inspections along with
enforcement and tracking of project sites that are found to be out of compliance. The County
will continue this program in the future, modifying as necessary to stay current with local and
state regulations.
Buffer Strips
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Buffer Strips are required along delineated boundaries of wetlands and along watercourses. The
County will continue to require buffer strips as land is developed and re-platted. Furthermore,
the County will explore options for increased monitoring of buffer strips to ensure that land
owners are not encroaching upon them.
Enforcement of Ordinances
The County staffs a full time code compliance officer to enforce the County’s Zoning Ordinance.
Continued enforcement of the ordinance will have a positive effect on the water management
issues raised in this Section.
Education/Public Involvement
Since many of the potential contamination threats to surface water and groundwater are humancaused, educational efforts can be significant in the prevention of further contamination.
According to a 1998 survey by the National Environmental Education and Training Foundation,
many Americans do not realize the level at which their behaviors impact the environment. The
survey also showed that when people understand their roles in water pollution, they were more
likely to engage in behaviors that will decrease pollution. The public must be empowered and
reminded of the impacts that each person can make and therefore must have access to accurate
information about their local watersheds. Access to, and understanding, this information enables
more citizens to voice their concerns of the environmental issues they face in their community.
Protecting water quality involves an ongoing commitment from all members of our communities.
Each one of us has many roles in which we affect water quality and many opportunities each day
to make choices involving the water quality of Scott County. Public involvement and education
are essential components of a long-term management strategy for Scott County. Education and
involvement allows the community to understand the impacts they may have on the soil, surface
water, groundwater, and overall ecology of the watershed in which they live. Education and
public involvement in the issues that face us today can facilitate learning how to alter our
behaviors and make better choices for our water resources in the future.
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The County is
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committed to continuing the current education programs that are in place, as well as developing
new programs as needed.
XIV. Summary
This Water Plan’s primary focus is to prevent degradation and improve the quality of Scott
County’s water resources, and the County as a whole. If its policies are not enforced, serious
consequences in the quality and quantity water resources will result.
This Plan establishes water management approaches that address:
ƒ
Water Quantity
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Comprehensive Land Use Planning
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Water Quality
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Development Pressures
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Erosion Control
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Natural Resource Inventories and
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Wetland Protection
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Groundwater Management
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Public Ditch Systems
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Recreation
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Enhancement of Public Participation;
ƒ
Fish and Wildlife Resources
Corridor/Greenways Studies and Acquisition
Information and Education
Through this assessment of issues the following goals and priority areas were identified:
•
Stormwater Management
•
Wetland Management
•
Surface Water Quality
•
Groundwater Management
•
Agricultural Management
•
Flood Management
•
Urban Development
•
Education
These goals are addressed in detail in Section 4 of this Plan.
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SECTION 4
Goals and Policies
I. Introduction
The goals and policies in this Plan were developed to address the following water management
categories as required by MN Rules, Chapter 8410.0080.
•
•
•
•
•
•
•
•
•
Water quantity
Water quality
Recreation and fish and wildlife
Enhancement of public participation; information and education
Public ditch systems
Groundwater
Wetlands
Erosion
Intergovernmental programs
The purpose of this section is to identify the goals of the Water Resources Plan that will provide
for the protection, enhancement, and management of water resources throughout the
unincorporated areas of the County. The goals and policies in this Plan represent, in part, the
goals and policies of the WMO that were established based on the recommendations of the initial
Citizens Advisory Committee and discussions with BWSR staff and local units of government.
Amendment 1, in particular Appendix C, amends the plan to be in conformance with the
Vermillion River Watershed Joint Power Organization (VRWJPO) Watershed Plan.
While the above list of categories is taken from Minnesota Rules Chapter 8410, this Plan
recognizes specific water management issues identified through the planning process as outlined
in Section 3 of this document. In Section 4, the specific water management issues are grouped
into eight major priority areas to provide implementation objectives for the Water Plan. The
County’s current Comprehensive Plan also outlines goals and policies that fall within the eight
priority categories within this Plan, and they are incorporated as appropriate. It should be noted
that the eight areas listed below are inherently interconnected in terms of management and
therefore the goal (and associated policies and objectives) listed under each issue area often
applies to, or is complementary to, other issue areas. An overlying theme within the goals is that
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it is often less costly to be pro-active with protection and management initially than to have to
pay for property and/or environmental damage and cleanup in the long run.
This section describes the specific implementation goals, policies, and objectives for eight major
areas, which encompass the water management categories listed below:
•
•
•
•
•
•
•
•
Stormwater Management
Wetland Management
Surface Water Quality
Groundwater Management
Agricultural Uses
Flooding
Urban Development
Education
Appendix B lists the Scott County proposed workplan for each goal area including timelines and
priorities.
II.
Plan Development
In February 2004, the Scott WMO Board adopted the WMO’s Comprehensive Water Resource
Plan. The Plan required all local units of government with land use authority to prepare a Local
Water Plan, consistent with the goals, policies, and objectives of the WMO’s Plan, within two
years from the date of the WMO’s Plan adoption. Section 4 describes the implementation goals,
policies and objectives to guide Scott County with water resource management and provide a
framework or basis for updating the current ordinances.
III.
Stormwater Management Goal
To manage the quantity and to improve the quality of runoff entering rivers,
streams, lakes, wetlands, and groundwater within the unincorporated areas of
Scott County.
Reason: Large or increased quantities of stormwater over presettlement conditions
leads to larger volumes of water and higher flow velocities, which in turn provide the
erosive power to damage stream channels and ultimately render them unstable. These
issues are transferred downstream as additional water and scouring power is added
along a watercourse. Many times the streams or rivers outlet into lakes, wetlands or
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other watercourses (receiving waters) and the material being transported is deposited in
areas where lower velocities decrease the water’s sediment carrying capacity. This leads
to issues associated with sedimentation in downstream areas, which can, among other
things, decrease floodplain storage, damage water resources, and destroy habitat. Loss
of topsoil due to erosion also renders soil less fertile and makes it harder to establish
vegetation on disturbed areas. Aside from the physical issues described above, there are
economic implications due to increased volumes and flow of stormwater. Unstable
stream channels over time have the ability to depress land values, damage property,
endanger high value structures and render prime building locations unbuildable directly
impacting the health, safety, and welfare of the County. In addition, unstable channels
undermine bridges, clog culverts, and can otherwise damage infrastructure requiring
costly repairs and ensuing legal problems for both public agencies and private
individuals.
With an increase in water quantity, there is usually a corresponding decrease in water
quality. Water quality is an important amenity in the County – both in terms of surface
water and groundwater. Stormwater can carry a variety of pollutants, which can affect
downstream areas as well as groundwater through infiltration.
Policies
1. Each development or land disturbing activity shall be responsible for managing its
stormwater effectively, either on or off-site; the preference being on-site management for
most non-transportation related projects. Regional off-site management shall be encouraged
for linear improvements and/or previously developed areas where on-site management is not
feasible/practical.
2. Scott County will promote and encourage a reduction in runoff rates, encourage infiltration
and promote increased groundwater recharge.
3. Stormwater will be managed to minimize erosion, with an emphasis on stabilizing flow rates
and velocities and prioritizing critical areas based on the landscape setting and existing
vegetation.
4. Promote development strategies, land use practices, and water management activities that
decrease and desynchronize peak flows, lengthen the watershed time of concentration, and
raise base flow levels.
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5. Promote development strategies to create and/or improve downstream conveyance systems.
New systems shall be encouraged where such systems do not currently exist and are needed
based on a detailed hydraulic analysis of the watershed and the demonstrated positive impact
the system would have on the public health, safety, and welfare. Improvements to existing
systems shall be encouraged where the existing system is inadequately sized, unstable, or
could otherwise be modified to further other established goals and objectives of the water
plan.
6. Promote strategies which allow for the orderly transition from privately maintained drainage
systems to public drainage systems as development occurs. The desired end result being a
public drainage system, contained within contiguous drainage & utility easements, that is
permanent, maintainable, and adequate to service the long-term drainage needs of the
County.
7. Use an overall philosophy of outcome based analysis and resource oriented management to
recognize and avoid potential downstream impacts from stormwater due to development/redevelopment activities. Scott County and the local watershed authorities (Townships) shall
be responsible for managing stormwater so as to maintain, stabilize, or improve downstream
drainage ways.
8. Identify and utilize existing, natural retention and detention areas for stormwater
management while maintaining or improving the existing water quality.
9. The construction of publicly owned, operated, and maintained regional stormwater ponds
shall be encouraged, where feasible, to promote storage through the construction of an
integrated regional retention area, as opposed to multiple smaller areas of on-site ponding, to
reduce public long-term maintenance costs and maintain efficiency. This policy recognizes
the difference between smaller on-site stormwater ponds that are routinely maintained by
property owners, and larger regional basins that will likely require public monies for creation
and routine maintenance.
10. The construction of stormwater infiltration areas shall be encouraged, where feasible and
environmentally beneficial, to promote the infiltration of stormwater to recharge subsurface
aquifers.
11. The construction of publicly owned, operated, and maintained regional stormwater
management systems shall be funded, in part or entirety, by development user fees.
12. Improve the long-term and institutional management and coordination of the county judicial
ditch system.
13. Educate key audiences, including developers, consultants, contractors, builders and local
units of government, on stormwater best management practices and other appropriate
methods, techniques or regulations to manage stormwater quantity and quality.
14. Runoff shall be routed to water treatment ponds or other acceptable facilities before
discharging to waters of the state.
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Objective 1.
Section 4, Page 91
Establish, evaluate, refine, and implement stormwater management,
erosion control and wetland protection rules and ordinances for
developments and land disturbing activities, including compliance
with NPDES Phase II.
Scott County will continue to require Stormwater Management Plans (SWMP) to be submitted
and approved for land disturbing/development activities. Specific requirements pertaining to
Stormwater Management Plans will be included with revisions to the County’s Zoning
Ordinance.
In practice, SWMPs for each development will be reviewed by the Natural
Resources Department based on a WMO approved LWP and updated Zoning Ordinance. The
following text items constitute a set of minimum criteria that are or will be included in the
County’s Zoning Ordinance:
Rate and Volume Control – The unincorporated township areas within Scott County are required
to meet presettlement conditions for rate control and a minimum volume control equivalent to
the volume calculated by multiplying ½” times the area of new impervious surfaces. A different
runoff volume control standard will be used in the Vermillion River watershed portions of the
County in accordance with the Standards of the VRWJPO. This Standard requires no increase in
the runoff volume with new development for the 2-year, 24-hour storm. Alternatives and
waivers to this standard may be allowed and incorporated into county ordinances as provided for
in the plans/standards of the respective Watershed Organizations. Additional volume control may
be required to minimize downstream impacts.
The County also anticipates completing an amendment to this Plan to establish numerical rate
control Standards for the 100-year critical event at County boundaries. This amendment will be
completed in 2008/2009 once the VRWJPO has completed its hydrologic modeling effort.
Furthermore, Stormwater Management Plans will be reviewed by the County to ensure the
following:
Impact to significant natural features is minimized – Review the site for steep slopes (also see
bluff setbacks under Objective 7), wetlands, wooded areas of significance, rare and endangered
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species habitat, areas designated by the County Biological Survey, areas covered by natural
resources inventories, or Local/County/Regional parks, trails and open space.
These areas
should not be developed without serious consideration by all stakeholders.
Impacts to receiving waters are minimized; TMDLs and NPDES Phase II requirements
considered – This Water Plan takes a proactive approach in assessing impacts to receiving
waters, which provides coordination with efforts in the TMDL and NPDES Phase II programs.
A final listing of impaired waters for the County was published in January 2003, updated in
2004, and will again be updated for 2006. With that listing the County will need to take part in
studies to set TMDLs on its listed water bodies. In addition, the listing of communities required
to provide NPDES Phase II permit applications and Stormwater Pollution Prevention Plans was
finalized in December 2002, and mandatory MS4 areas were required to file Notice of Intent
with the MPCA by March 10, 2003. The NPDES Phase II program requires several programs be
put in place, including education. The County intends to coordinate educational programs and
provide technical and educational assistance where needed.
Runoff from impervious area is minimized – Minimize the amount of impervious land from each
new development by considering the following low impact development options for applicable
projects:
•
•
•
•
•
•
•
•
•
Decreasing local street width where feasible
Limiting paved parking lot space
Smaller driveways
Maximize open space while incorporating smaller lot sizes
Bio-retention – use landscaping and soils to treat and infiltrate stormwater runoff
Eliminate curb and gutter where practicable
Filter strips – Look for vegetated areas that can filter sheet flow, removing sediment and
other pollutants, and increasing the time of concentration
Disconnect impervious areas by allowing runoff from small impervious areas to be directed
to pervious areas where it can be infiltrated or filtered, such as rain gardens
Increase buffers around streams, steep slopes, and wetlands to protect from flood damage and
provide additional water quality treatment
Volume reduction techniques – Reduction of stormwater volume can be advantageous for several
reasons, but the two major reasons are to decrease the amount of surface runoff entering
conveyance systems (thereby increasing recharge of groundwater) and to provide areas where
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water can cycle through the soil profile to help remove pollutants prior to entering the
groundwater. Properly designed volume reduction strategies can help restore the water balance
that existed prior to development, providing groundwater recharge, control of peak flows from
stormwater and protection of stream banks from erosion due to high flows.
There are a number of techniques used to reduce stormwater volumes that make use of
infiltration to remove pollutants and to recharge or replenish the groundwater. Infiltration
techniques include, but are not limited to, infiltration basins, infiltration trenches, changes in
vegetative cover, and dry wells. Infiltration capacity and rate at the land surface and shallow
subsurface depend on the soil characteristics, geology and the surface drainage characteristics
among other things.
The soil physical, chemical and biological characteristics, as well as
landscape position will influence how surface and groundwater interact. A substantial advantage
of infiltration is that in areas with a high percentage of impervious surfaces, infiltration is one of
the few means to provide significant groundwater recharge.
Volume reduction through infiltration of water can facilitate the removal of pollutants through
adsorption onto soil particles, and biological and chemical conversion within the soil profile.
Infiltration is recommended in areas where the soil properties are conducive to the appropriate
infiltration capacities, infiltration rates, and saturated hydraulic conductivity. In addition, surface
conditions, soil profile depth and layering, and a texture conducive to adsorption of pollutants
shall be considered.
Although not as easy to achieve on sites with clayey soils, volume reduction techniques are still
required for all development sites. Unlike areas that are conducive to infiltration, poor sites
should not rely on infiltration techniques to account for all volume reduction or rate control.
Development on poorly conducive soils should incorporate best management practices to
maximize the volume reduction to the extent possible.
Sufficient water retention/detention ponds – Water retention/detention ponds shall be designed
for specific purposes and functions as part of an overall stormwater management system by a
licensed professional. The nomenclature identifying the specific purpose and functions of ponds
shall be recognized by Scott County in accordance with the following definitions:
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Stormwater Detention Pond – A natural or created ponding area that provides temporary storage
of excess stormwater for the purpose of attenuating the peak rate of runoff by controlling the rate
of pond discharge. Ponding areas that drain completely between storm events are dry detention
ponds. Ponding areas that provide temporary storage in combination with a permanent wet pool
are wet detention ponds.
Stormwater Retention Pond – A natural or created ponding area which provides permanent
storage of excess stormwater for the purpose of attenuating the peak volume of runoff, from
which the only release of flow is by infiltration or evaporation.
Stormwater Quality Pond - A created ponding area per W.W. Walker (1987) criteria, which
provides a permanent pool for the purpose of sediment and pollutant removal to reduce water
quality impacts of urban development.
Infiltration Area – A stormwater retention method for the purpose of reducing the volume of
stormwater runoff by transmitting a flow of water into the ground through the earth’s surface.
Additional design criteria for wet detention ponds – the following design criteria shall be used in
addition to standards set forth in “Design Criteria for Wet Detention Ponds” (Walker, 1987):
a) A minimum protective shelf extending ten feet into the permanent pool with a slope
of 10:1 beyond which slopes would not exceed 4:1.
b) A protective buffer strip of permanent vegetation surrounding the permanent pool at a
minimum width of 25 feet.
Stormwater conveyance – At a minimum, the stormwater conveyance system shall be designed
for a 10-yr-24-hour storm event. It is important to ensure that the structure maintains existing
discharge rates and treatment. Reductions or increases in the capacity of stormwater conveyance
systems may be determined to be appropriate based on a comprehensive analysis of specific
watersheds and existing conditions. For example, a stormwater conveyance system reduction
may be warranted where a narrow bridge span restricts flows significantly lower than a 10-yr-24-
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hour storm event. Reductions in stormwater conveyance capacity shall require approval of Scott
County as part of a SWMP.
Creek/stream conditions are considered – When reviewing plans that involve a direct discharge
to a creek or stream, the design engineer shall determine the bankfull stage and the
corresponding flows for that stage as part of the downstream evaluation. Bankfull discharge is
associated with a momentary maximum flow that, on the average, has a recurrence interval of 1.5
years. If this recurrence interval increases, the stream dimension, pattern, and bed features will
be altered. Erosion and sedimentation will increase and the meander pattern will be altered. To
protect stream channels from erosion, the runoff shall be stored and released in such a gradual
manner that the critical erosive velocities will seldom be exceeded in downstream channels.
Shoreland Ordinances are followed – All developments and land disturbances within a
designated Shoreland District shall meet the requirements of Chapter 70: SL, Shoreland District
from the Scott County Zoning Ordinance, as amended.
Objective 2.
Establish stormwater management system maintenance standards.
Design
All stormwater conveyance systems shall be designed in a manner to minimize the need for
maintenance and reduce the chances of failure. Design guidelines should be consistent with
Protecting Water Quality in Urban Areas (MPCA, 2000), as amended.
As property develops, public drainage and utility easements shall be provided by the property
owner for public stormwater management systems for access, facility inspections and
maintenance. Easements shall be recorded and dedicated to the township prior to the approval of
a final plat or issuance of a building permit.
Final design shall be approved by Scott County and the respective Township. As-built plans
shall be submitted to the County and Township upon project completion.
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Routine and Non-routine Maintenance
All stormwater Best Management Practices (BMPs) shall be maintained according to the
measures outlined in the most recent version of Protecting Water Quality in Urban Areas
(MPCA, 2000), and as detailed in the SWMP. Non-routine maintenance includes maintenance
activities that are not included in the SWMP, such as pond dredging or major repairs to
stormwater structures.
The applicable township responsible for routine maintenance shall be designated in the SWMP.
Inspections shall be conducted on a regular basis during construction by County and/or
Township staff to ensure compliance with the SWMP.
Maintenance agreements shall specify responsibilities for financing maintenance tasks.
The township responsible for maintenance shall inspect permanent stormwater BMPs on a
regular basis, not to exceed once every five years.
As permitted by law, authorized representatives of Scott County may enter public and private
properties to conduct on-site inspections. Representatives will work with individual property
owners or agencies to access restricted areas where deemed appropriate by Scott County.
Authorized representatives of the County will conduct random inspections as may be deemed
appropriate to confirm the information in the filed reports.
Objective 3.
Encourage
restoration
on
damaged/susceptible
banks/corridors for erosion control as development occurs.
stream
A sound approach to stream bank erosion is a combination of watershed management and site
specific restoration along streambanks. The first priority is to effectively manage runoff from
the watershed or subwatershed of concern by implementing the preceding procedures. The next
step is to inventory sites within the watershed or subwatershed and develop cost-effective
methods to repair and restore eroded streambanks. Bioengineering and traditional engineering
are effective techniques that protect streambanks from erosion. Bioengineering uses natural
means to stabilize the banks through planting trees and structural correction by making the
stream or river meander more to reduce flow velocity. Traditional techniques include armoring
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the banks. This technique should only be used in small areas because of the high cost and the
issue of passing problems to downstream areas.
Objective 4.
Develop stormwater management plans that identify capital and
operational costs for and methods to assess appropriate costs to new
development for stormwater management.
Develop Fee Schedule – Scott County is facing increasing growth pressures. Managing
stormwater from development/redevelopment projects is a major undertaking for the County
which requires significant resources and management. Stormwater management plans for
development projects require on-site and off-site improvements. In concert with the WMO for
regional needs, the County will research the opportunity to define long range capital and
operational costs and require developers to pay their fair share. Adequate security for
construction of improvements and installation and maintenance of erosion control measures
should be posted by developers to ensure the integrity of the stormwater management system for
development projects.
Enforcement – Land disturbing activities will be inspected regularly by County and Township
staff to ensure compliance with stormwater and erosion and sediment control plans as stipulated
in the 3-party Developer Agreements signed by the Developer, the County, and the Township. If
the plans are not followed or if it is not maintained throughout the required duration of the
project, the posted surety will be used to repair any damages caused by non-compliance if, after
notice by the County or Township, the damage is not repaired by the responsible party. The
County and Township have equal enforcement authority through the Developer Agreement.
Objective 5.
Develop a regional stormwater strategy using hydrologic/hydraulic
modeling.
The County will work with the WMO and other watersheds in the County to prepare models and
design a regional stormwater management plan. The Plan will help identify the best areas for
water attenuation and/or water treatment to discourage multiple ponds from occurring with every
development, reduce maintenance, and enhance overall storage capacity for the watershed.
Modeling will also assist in establishing fee schedules for specific watersheds based on the
identified costs/need for improvement and/or maintenance. Cost sharing across jurisdictions will
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be pursued to repair and/or maintain overland flow channels and streams in a safe and stable
condition.
Objective 6.
Mitigate and reduce the impact of localized flooding when feasible.
The County will encourage developers to mitigate and reduce the impacts of localized flooding
as part of the design and review of SWMP. The County will also work with the WMO to
identify potential areas for regional ponds.
Objective 7.
Mitigate and reduce the impact of stormwater discharge on
downstream conveyance systems.
As part of the review of individual SWMPs, the County will review each proposal relative to the
downstream carrying capacity and condition. Based on a combination of factors including poor
past development practices, changes in land use, and environmental conditions, certain
downstream conveyance systems are not able to accommodate the rate and volumes of water
they are currently accepting. This inadequacy has resulted in erosion, impacts on wildlife
habitat, property damage, and significant development restrictions. The objective of the County
is to require the improvement of downstream conveyance systems with the development of
property contributing to the conveyance system. The amount of improvement to the downstream
conveyance system will be commensurate with the existing condition of the system.
A developer may make an in-kind or monetary contribution to improve downstream conveyance
systems, in lieu of physical improvements where determined appropriate by the County.
Contributions may be made in this regard only where the inadequate downstream conveyance
capacity and condition will not be further reduced/impacted, and where a designed system with a
construction estimate exists.
The intent being that the County or a township may collect and
assemble funds to implement projects that are beyond the scope of a specific proposal.
As discussed in Section 3 of this document, landlocked basins also present a management issue
for the County, both in terms of flood levels associated with the basins and with respect to
downstream impacts should the basin be provided with an outlet. With these issues in mind, the
County will require the following for landlocked basins:
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Evaluation of flood levels – an evaluation of flood levels for landlocked basins shall be
completed to determine their capacity to accommodate increased runoff without negatively
affecting public health, safety, and welfare.
Allowance of Outlets – In those areas planned as “Urban Expansion” or “Urban Transition” (as
provided in the County’s most recently adopted Comprehensive Plan Update) the County will
allow outlets for landlocked basins, provided that the following criteria are met.
•
There is a demonstrated need for an outlet to protect existing structures and infrastructure,
•
Flood storage is retained in the basin to the extent possible while preventing damage to
property adjacent to the basin,
•
Proposed development tributary to the land-locked basin has incorporated runoff volume
control practices to the extent practical.
•
All downstream conveyance channels can accommodate the runoff added by the outlet.
Outlets Discouraged – In other areas of the County, outlets from landlocked basins will be
discouraged in favor of non-structural approaches to flood protection. Such approaches could
include mapping and preservation of natural floodplain areas, removal of flood-prone structures,
and encouragement of the use of flood insurance.
The erosion of and instability of bluff areas are of concern within the unincorporated areas of the
County and as such will have requirements to facilitate management of these areas. A bluff is
defined as a topographic feature such as a hill, cliff, or embankment in which the average grade
of any portion of the slope is 30 percent or greater and there is at least a 25-foot rise in elevation.
The top of the bluff is defined as the point on the upper part of a bluff where there is a clear
break in grade or where the average slope levels off to 18 percent or less.
All land disturbing activities in bluff areas must comply with the bluff standards identified in the
County’s Zoning Ordinance. The minimum standards shall include a bluff impact zone of 25
feet from the top of the bluff in which the clear-cutting of existing natural vegetation other land
disturbing activities shall be prohibited. In addition setbacks for all bluffs are established that
pertain to all structures, stormwater ponds, infiltration systems, soil saturation-type features, and
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ISTS. The minimum setbacks shall be 50 feet for stormwater ponds, infiltration systems, soil
saturation-type features and ISTS systems. For structures, the minimum setback shall be 30 feet;
and requires that no stormwater is directed over bluff face and stormwater runoff, including roof
drainage, is collected and conveyed to a stable discharge point. The bluff impact zone, runoff
management, and setbacks will help facilitate stability of the bluff areas within the County,
thereby reducing erosion/sedimentation and reduce future costs to provide clean up of areas,
culverts, and bridges where deposition takes place.
IV.
Wetland Management Goal
To protect and enhance wetland ecosystems by managing contributing
watersheds, and to ensure/encourage a measurable net gain of wetland functions
and acreage throughout the County.
Reason: Protection of wetland resources is required by federal and state policies, which
are supported by regulations. Wetlands provide a variety of functions and values, which
are important to the overall character and function of the watersheds that they are a part
of. Functions are physical, chemical and biological processes that take place within a
wetland system. Values are the social, economic, or ecological benefits that wetland
systems provide to the general population. Functions and values for wetland resources
within the WMO should be identified prior to changes within the landscape in order to
preserve, manage and maintain these features to the greatest extent possible.
Examples of functions include water storage, flood desynchronization, nutrient retention
and transformation, wildlife and aquatic habitat, groundwater recharge and discharge
areas, and influence on atmospheric processes. The types and numbers of functions that
a wetland performs are based on many factors, and not all wetlands perform all functions
nor do they perform functions equally well.
Examples of wetland values include passive and active activities such as aesthetics,
education, archaeological study, hunting, and bird watching. Values are not easily
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measured because what is valuable and important to one person may not be valuable and
important to their neighbor.
Policies
1. Achieve no net loss of wetlands in the unincorporated areas of Scott County, in conformance
with the Minnesota Wetland Conservation Act (WCA) and associated rules (Minnesota Rules
8420).
2. Encourage wetland avoidance for all new developments and land disturbing activities.
3. Require mitigation of unavoidable wetland disturbance by replacing the lost wetland
functions and values in the same major subwatershed with a wetland of equal or greater value
at the replacement ratio defined in the Comprehensive Wetland Management Plan (to be
developed). In the interim, replacement ratios shall be dictated by the WCA.
4. Require transportation projects to pursue wetland mitigation projects to the extent possible
along the transportation corridor. Where this is not feasible, the transportation project
manager should work with adjacent landowners, LGUs, SWCD, County, state, or federal
agencies to identify and provide mitigation areas as close to the project area as possible
(Thus does not preclude use of the BWSR Road Replacement Program).
5. Identify areas within the County that are conducive to wetland restoration. Work with
landowners, SWCD, and appropriate agencies to accomplish wetland restoration within the
identified areas.
6. Require all identified wetland habitat impacts to be mitigated through wetland enhancement,
restoration, or creation.
7. Manage changes in volume and quality of local stormwater systems to minimize negative
impacts to existing wetland functions, value, or biological diversity. This includes a
proactive approach to erosion control enforcement around affected wetland areas, mitigation,
restoration, or creation.
8. Identify and preserve wetlands for water retention, recharge, soil conservation, wildlife
habitat, aesthetics, and natural enhancement of water quality.
9. Require a buffer, to include a filter strip, around each wetland commensurate with its
management classification.
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10. Increase participation of property owners, developers and contractors in wetlands and
wildlife land management assistance programs, and decrease violations of wetland
regulations through better education programs.
Objective 1.
Develop and implement a Comprehensive Wetland Management Plan,
to include a wetland protection program.
The Scott SWCD has completed a Level III wetland inventory of the County. A Level III
inventory includes the mapping (location), numbering and data collection of drained, altered and
existing wetlands in the County. A Level III inventory differs from a Level I or II inventory in
that it adds the mapping, numbering and data collection of existing wetlands. The Wetland
Inventory Guidebook (BWSR, 1991) contains further detail. An evaluation of all wetlands
identified in the inventory is an important element in the development and implementation of a
comprehensive wetland management program. The County will work with the WMO and the
Townships in developing the comprehensive wetland management plan. The County will work
to identify and implement an evaluation method that includes prioritization, protection,
mitigation and/or compensation. Data will be provided via the County’s GIS and will be
available to the public.
It is estimated that originally there may have been 60,000 acres of wetlands in Scott County (26
percent of Scott County land). Drainage and filling has eliminated over 50 percent of this
acreage. Current figures indicate approximately 25,000 acres of wetlands remain. The goal of a
comprehensive wetlands protection program should be to ensure that in the short term there is no
net loss of wetland function and acreage. Whereas, in the long term there is a measurable gain of
wetland function and acreage. WCA provides for the development of comprehensive wetland
management plans to compliment the Water Plan. The Comprehensive Wetland Management
Plan would include the following items:
•
Comprehensive land-use planning should have wetland protection integrated into its
development. Special measures will be outlined to protect wetlands, including identification of
prime wetland sites, providing policy protection, allocating funding for special projects, and
designing compatible infrastructure. Protection and management for upland buffers and natural
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corridors between wetlands should be included in these measures. Wetland protection will be
coordinated with adjacent LGUs.
•
Preservation programs will address the protection of significant wetlands and their
protective buffer areas. These programs should be consistent with, and to the extent possible, be
incorporated into the County’s comprehensive plans. Innovative techniques to conserve and
protect these areas will be promoted such as:
1. Private Stewardship: Landowners will be encouraged to protect wetlands by guarding
against activities that may degrade wetland functions and values. Private landowners will
be made aware of federal and state economic incentives to encourage and assist with
stewardship. This will reduce the financial burden that may be associated with the
ownership of undevelopable land, and help to ensure the continuation of public benefits
for wetlands. Economic incentives may include reduced property taxes for wetland areas,
density credits, and transfer of development rights.
2. Land trusts: A land trust is a non-profit organization whose purpose is to preserve open
space within a specific geographic area. Local governments will work with private land
trusts to promote wetland preservation.
3. Public acquisition: Once the identification and classification inventory is complete,
wetlands can be acquired in whole or in part, as the availability of funds allows.
•
Restoration actions will be incorporated into comprehensive, wetland protection efforts to
facilitate achievement of an overall gain of wetlands in the County. Restoration, although often
considered a part of regulatory mitigation efforts, fills an equally critical, non-regulatory role.
Wetland restoration involves reestablishing a wetland’s functional characteristics and processes
that have been lost.
Native vegetation, as recommended in Wetland Plants and Plant
Communities of Minnesota and Wisconsin (Eggers and Reed, 1997), should be used in all
restoration projects, and provisions made for control of invasive and exotic species.
•
Regulation will be included to regulate development and mitigate its effects on wetlands.
The regulatory program will be designed to be as restrictive as the requirements of WCA at a
minimum. The basic elements of the regulatory plan will include:
1. A “no net loss” goal;
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2.
3.
4.
5.
6.
7.
8.
9.
Section 4, Page 104
A clear definition of “regulated wetlands;”
An established method of delineating wetlands;
A method of qualitatively categorizing wetlands;
An established methodology to evaluate functions and values;
A definition of “regulated activities;”
Wetland buffer zones;
Standards for use and protection of wetlands; and
Enforcement.
Wetlands are regulated by a number of agencies. Depending on the type of wetland, the intended
use will dictate which agencies will need to be contacted and the permits that have to be
obtained. The MnDNR, COE, NRCS, and the various local units of government (townships in
Scott County) are the regulatory authorities that an individual must notify if wetland impacts are
proposed.
A Local-State-Federal Project Notification Form has been developed for use by individuals
proposing wetland impacts. This form is used to notify the MnDNR, USCOE, and the township
offices of a project or work proposed that falls within their jurisdiction.
•
Education programs will be encouraged, coordinated with other education programs and
can take on many forms. A volunteer program can be used for various activities such as
distributing educational materials, conducting wetland field trips or monitoring the health of
wetlands. Educational materials should be designed to provide information on the functions and
values of wetlands, the importance of wetlands preservation, methods for landowners to protect
and preserve wetlands, and a basic overview of the local regulations regarding wetlands.
Wetland education should also be provided in the local school systems with activities available
to different age groups for “hands-on” learning.
•
Program evaluation should be developed as a means of determining the success of
wetland protection programs. The program evaluation may involve inspection and reporting
requirements to monitor the success of mitigation projects; a permit tracking system;
measurement of acreage and functions of wetlands lost, and those enhanced, restored and
created; a method of calculating (in quantitative and qualitative terms) the wetland resources
preserved; and a means of evaluating educational efforts in raising the community’s awareness
with respect to wetland values.
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Objective 2.
Section 4, Page 105
Establish wetland buffer requirements for structures, land disturbing
activities, and adjacent uses in new developments based on wetland
function levels.
A buffer is a transitional area between two different land uses that mitigates the effect of one
land use on the other. A wetland buffer zone is an area that surrounds and protects a wetland
from adverse effects of activities on adjacent lands. Secondary benefits of buffers include
creating open space between the resources and adjacent uses, helping to maintain or improve
wildlife habitat values and wetland hydrology, protecting the aesthetic value of the site and
minimizing property damage from floods. A buffer zone should be of adequate width to provide
the following functions:
•
•
•
•
Stabilize soil and prevent erosion;
Filter suspended solids, nutrients, and harmful or toxic substances;
Moderate effects of stormwater runoff (including volume reduction); and
Support and protect plant and animal species and their habitats.
Determining Width of Buffer – All wetlands and public waters wetlands in the unincorporated
areas of Scott County are subject to buffers as shown in Table 4.1. A functions and values
analysis will be required with all wetland delineations submitted to the County. The delineator
will use the most recent version on MnRAM. The Applicant is responsible for completing and
submitting the delineation and MnRAM assessment. Applicants must meet the minimum buffer
requirements outlined in Table 4.1 based on the MnRAM assessment. The County will review
the MnRAM assessment to determine that the applicant is providing the correct buffer widths.
Buffers shall be measured from the delineated wetland edge. Average buffer widths vary from
25 to 65 feet depending on the type of wetland the buffer surrounds. The minimum buffer width
is 25 feet which is also a no impact zone. There is also a building setback of 35 feet from the
delineated wetland edge with the exception of stormwater ponds for which the setback is 25 feet
from the 100 year high water level. There will be some minor exemptions for transportation
projects, on a case by case basis.
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TABLE 4.1: Buffer Standards
Buffer
Requirement
Average Buffer
Width
Minimum Buffer
Width
Exceptional
High
Moderate
Low
Stormwater
65
50
35
25
0
25
25
25
25
0
Wetland Ratings
“Exceptional” Wetland – Wetlands assigned the exceptional rating using the most
recent version of MnRAM for evaluating wetland functions. These wetlands are most
highly susceptible to human impacts, are most unique, have the highest community
resource significance such as rare species habitats, and similar characteristics.
“High” Wetland – Wetlands assigned the high rating using the most recent version of
MnRAM for evaluating wetland functions. These wetlands are relatively undisturbed but
exhibit evidence of more disturbance or degradation than Exceptional wetlands. High
wetlands have conditions and functions that are susceptible to human impacts, are
connected to other wetlands or waterways, and may contain locally significant or rare
wetland types.
“Moderate” Wetland – Wetlands assigned a moderate rating using the most recent
version of MnRAM for evaluating wetland functions. These wetlands typically provide a
diversity of habitats, and are connected to other wetland or upland habitats to provide
wildlife habitat.
“Low” Wetland – Wetlands assigned a low rating using the most recent version of
MnRAM for evaluating wetland functions. These wetlands tend to be less susceptible to
further impacts than the other wetland management classifications. They also have low
diversity and connectivity to other wetlands and waterways.
Stormwater Ponds – Are designated strictly for treating and retaining stormwater.
More specific buffer requirements may take effect after the establishment of a wetland
ordinance, which will be specified in the proposed wetland management plan. The above
standards will serve as interim requirements for newly platted or replatted areas until new
requirements are established by the comprehensive wetland management plan. A functions and
values analysis will be completed with each wetland delineated for a project. The delineator will
use the most recent version on MnRAM.
Signing Buffer Perimeters – The County shall require signs to clearly designate the boundaries of
all buffers within new residential developments in the unincorporated areas of the County. Signs
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should include warnings about fines for disturbing and/or developing buffers. Signs should be
placed approximately 200 feet apart, and the signs should be a minimum of 5 inches wide by 7
inches vertical, have a brown field with white lettering, and be securely mounted on a minimum
4 foot signpost. The developer will pay for these signs.
V.
Surface Water Quality Goal
To preserve and enhance surface water quality in Scott County’s water bodies
and watersheds, commensurate with the eco-region and desired uses.
Reason: Protection of surface water quality is addressed by federal and state policies,
which are supported by regulations. Surface water is an important resource in the
County.
Failure to address water quality issues can lead to impairment of water
resources and can affect recreational uses, aquatic habitat, wildlife, groundwater quality,
and other water use activities.
The Minnesota Pollution Control Agency published a proposed list of impaired waters
for listing under the Clean Water Act Section 303(d) in late 2001. This proposed list was
submitted to the Environmental Protection Agency in October 2002 and finalized in
January 2003. The list was updated in 2004 and will again be updated for 2006. This
requires that Total Maximum Daily Loads (TMDLs) be set for these waters within a
specific time-frame (usually five to ten years). Several water bodies located completely
or partially within Scott County are on the list:
Streams/Rivers
•
Credit River, headwaters to the Minnesota River
Listed for turbidity
•
Sand Creek, Porter Creek to the Minnesota River
Listed for turbidity and Fish IBI
Lakes
•
Fish, McMahon, Cedar, O’Dowd, and Thole (Schneider) are all listed for excess
nutrients.
•
Cleary, Cedar, Fish, and O’Dowd are all listed for mercury.
Scott County Water Resources Plan – Amendment 1
October 2007
Goals and Policies
Section 4, Page 108
In addition, the Minnesota River runs along the entire western and northern boundaries
of Scott County and has several listings, which due to the County’s adjacent land, are of
note:
•
Minnesota River, Bevens Creek to Sand Creek
Listed for mercury, PCB, and turbidity
•
Minnesota River, Sand Creek to Carver Creek
Listed for mercury and PCB
•
Vermillion River, Head waters in Scott County to Hastings
Listed as impaired for aquatic recreation due to excessive fecal coliform
bacteria
Policies
1.
Expand existing water quality monitoring networks.
2.
Improve the quality of surface water monitoring programs and involvement, as well as
the information derived from monitoring data.
3.
Target high priority water bodies for water quality projects; this includes working with
those waters listed as “impaired” by the MPCA for listing under Section 303(d) of the
Clean Water Act.
4.
Secure stable funding to augment water quality projects and local programs.
5.
Obtain usable, transferable data for road salt management, and provide projects and
workshops for Public Works personnel to improve proper storage practices and use
salt-tolerant species in County ditches (less sand and proper salt management will
minimize environmental impacts).
Objective 1.
Support the WMO’s objective to develop and implement water
quality monitoring and diagnostic programs to preserve, protect, and
improve the water quality of the County’s surface waters.
This will identify water body conditions, monitor the effects of runoff management efforts, and
determine the need for changes in the Water Resources Plan.
Metropolitan Council Environmental Services (MCES) staff and its CAMP monitor Metropolitan
area lakes to provide a comprehensive database which allows cities, counties and watershed
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Section 4, Page 109
management organizations to better manage area lakes. The success of the MCES CAMP
program over the past several years should encourage shoreland owners to become more active
citizens in monitoring the health of lakes in the County. A similar MPCA program for streams,
the CSMP network “combines the knowledge and commitment of interested citizens with the
technical expertise and resources of the… MPCA.” More information on CSMP can be found at
the program’s web site: http://www.pca.state.mn.us/water/csmp.html.
Recommendations for lake monitoring parameters are, but should not be limited to, phosphorus,
chlorophyll-a, and Secchi disk readings.
The recommended stream monitoring parameters
include, but are not limited to, nitrates, fecal coliform, sediment, and flow/loading. These are
minimum parameters that will allow Scott County to gain an understanding as to how the
monitored lakes and streams respond to different environmental factors.
The data that is
collected during monitoring will also guide Scott County and the Scott WMO in recommending
the necessary water quality improvement measures when and where necessary.
Objective 2.
Support the WMO’s objective to analyze monitored data, identify
trends, and recognize surface water quality problem areas.
Many of the County lakes, streams, and rivers have little or no water quality data. This presents
a challenge when attempting to set reasonable and attainable goals. Establishing a baseline for
water quality and quantity using sound science, consistent measuring practices and units, and a
network of sampling sites is an ongoing objective. This data will be used to set specific water
quality goals, monitor pre- and post-construction runoff, measure the effectiveness of
agricultural and residential BMPs as well as gauge educational and enforcement efforts
throughout the County. Please refer to the lake water quality reports contained in Appendix E,
Lake Water Quality Report, of the Scott WMO Comprehensive Water Resources Plan (May
2004) for lakes in Scott County. The objectives are to:
•
•
•
•
•
Provide water quality data in a readily available (easily accessible) format for staff, board
members, citizens, and watershed managers;
Analyze data and identify problem areas;
Establish baselines and set priorities for future monitoring sites;
Set short and long term goals for the watershed plan; and
Provide a framework for water quality data collection, which can be updated on a yearly
basis, or as data becomes available.
Scott County Water Resources Plan – Amendment 1
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Goals and Policies
Objective 3.
Section 4, Page 110
Support the WMO’s objective to establish implementation programs
through the establishment of water quality goals and the evaluation of
the effectiveness of management activities on the affected water
bodies. Proactively work with the MPCA to address Total Maximum
Daily Load issues with listed (303d) waters.
The goals will be commensurate with the desired lake uses. Evaluation criteria will be used such
as total phosphorus, chlorophyll-α concentrations, and water transparency. This will include a
determination of both desirable water quality and permissible phosphorous load for each water
body.
The federal Clean Water Act requires states to adopt water quality standards to protect the
nation’s waters. These standards define how much of a pollutant can be in a surface and/or
groundwater while still allowing it to meet its designated uses, such as for drinking water,
fishing, swimming, irrigation or industrial purposes. Among these pollutants are un-ionized
ammonia, mercury, fecal coliform bacteria and particles that limit the depth to which sunlight
can penetrate the water. A water body may also be considered impaired if its level of dissolved
oxygen is too low or its temperature is too high. TMDLs are established to ensure that the water
quality of the impaired water body will be brought up to water-quality standards and maintained
at those standards. Rivers and streams may have several TMDLs, each one determining the limit
for a different pollutant. Several water bodies in Scott County are on the impaired waters list as
indicated at the beginning of this section.
The MPCA is the lead agency in the State of Minnesota for establishing TMDLs. Scott County
will work with the MPCA and the WMO to establish TMDLs. The County may be able to assist
the MPCA through the use of historical data, monitoring records, and staff time.
For each pollutant that causes a water body to fail to meet state water quality standards, the
federal Clean Water Act requires the MPCA to conduct a TMDL study. A TMDL study
identifies both point and nonpoint sources of each pollutant that fails to meet water quality
standards. Water quality sampling and computer modeling determine how much each pollutant
source must reduce its contribution to assure the water quality standard is met.
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Goals and Policies
Objective 4.
Section 4, Page 111
Minimize water quality impacts from new development and land
disturbing activities by requiring the use of best management
practices and by providing rules and ordinances to implement
erosion/sedimentation control practices.
BMPs are outlined in “Protecting Water Quality in Urban Areas” (MPCA, 2000), as amended.
BMP requirements are incorporated in the Scott County Zoning Ordinance for erosion and
sediment control.
Dense vegetation slows water movement allowing for greater infiltration, and established
vegetation improves the soil structure.
Soil structure increases infiltration and enhances
chemical degradation and nutrient utilization by biological and chemical processes. Therefore,
the best plants for water quality purposes have dense surface growth, create a uniform ground
cover, and have a fibrous root structure. Native prairie grasses are more effective than short
mowed lawns, and cool season grasses provide additional filtration benefits because they have
active growth during the spring runoff (University of Illinois-Extension, 1998).
Native
vegetation cover on as much property as possible provides the best filtration.
The current Scott County zoning ordinance requires a 25-foot filter strip of permanent lowmaintenance, drought-tolerant, native vegetation around wetlands. This will be incorporated into
the revised Ordinance and included as part of the buffer requirement. The MnDNR regulates
shoreland use around lakes greater than 25 acres (10 acres in municipalities) and rivers with a
drainage area of 2 square miles or more. On lakeshores, required building setbacks range from
50 to 150 feet, and for rivers the building setback is 50 to 150 feet. The shore impact zone is the
area immediately adjacent to a lake or stream, and is classified as one-half of the building
setback. For agricultural uses, the impact zone is 50 feet.
Improper storage and handling of chemicals such as road salt degrades and contaminates surface
and groundwater. To minimize contamination, storage locations of snow and salt should take
into consideration proximity to surface water, including open ditches, drain tile lines, lakes, and
streams. As development expands, monitoring of priority water bodies will be required to
determine potential effects of snow and salt runoff and deposition.
Monitoring of state
regulations regarding road salt storage and use, as well as instituting BMPs for road salt storage
Scott County Water Resources Plan – Amendment 1
October 2007
Goals and Policies
Section 4, Page 112
and use will be undertaken as part of this Plan and is also covered under the County’s NPDES
Phase II MS4 Storm Water Pollution Prevention Program.
Objective 5.
Maintain active involvement with the NPDES Phase II program.
Scott County and several townships within the County have established Storm Water Pollution
Prevention Plans (SWPPP) under the NPDES Phase II MS4 Program. The NPDES Phase II
permit requires that a number of elements be met in order to maintain compliance with the
permit. Scott County will provide resources and work with those entities to ensure that the
elements of the permit are met and are ongoing.
VI.
Groundwater Management Goal
To protect groundwater quality and improve groundwater supplies through the
effective implementation of this Plan and the Scott County Groundwater
Protection Plan.
Reason: Groundwater resources are protected by federal and state policies, which are
supported by regulations. Scott County relies on groundwater for its domestic, municipal
and industrial supplies. Scott County adopted a Groundwater Protection Plan in 1999.
The Plan outlines existing and potential issues as well as opportunities for groundwater
protection and management. The rapid increase in the population of Scott County is
intensifying land development pressure, increased groundwater use, and additional
potential for groundwater contamination through land use changes.
Policies
1. Promote ongoing evaluation of land use impacts on groundwater quality and quantity.
2. Provide data to the general public regarding inventoried groundwater resources and
incorporate information into the County’s GIS with updates as appropriate.
3. Support identification and reduction of groundwater contamination from both point and nonpoint sources.
4. Continue to support programs that promote efficient and effective administration of
groundwater pollution regulations.
Scott County Water Resources Plan – Amendment 1
October 2007
Goals and Policies
Section 4, Page 113
5. Encourage data collection, development and consistent updating of a groundwater flow
model and groundwater recharge model for Scott County.
6. Support enforcement of County ISTS and community septic system ordinances.
7. Support continued management of the County Feedlot Program.
8. Encourage an increase in well water testing by WMO residents to identify potential aquifer
contamination.
9. Promote water conservation strategies to conserve groundwater resources and reduce percapita water use to conserve groundwater resources.
10. Provide education on wells, wellhead protection, groundwater/surface water interactions, and
the County’s groundwater resources.
Objective 1.
Implement the strategies and objectives of the Scott County
Groundwater Protection Plan.
This Water Resources Plan incorporates and implements the policies and recommendations of
the Scott County GWPP. This will assure County residents access to potable water by protecting
existing and future groundwater resources. The GWPP identifies existing and potential issues as
well as opportunities for groundwater protection. County staff and a local citizen group prepared
the GWPP with assistance from local, state and federal agencies. The Plan was approved by the
County Board on March 23, 1999. It contains groundwater data and issues relevant to Scott
County residents, and it maps an implementation and update strategy to be followed in the years
ahead.
Objective 2.
Provide education on the hydrologic cycle, groundwater and
groundwater/surface water interactions.
The average person has not had formal education pertaining to groundwater, hydrogeology, or
hydrology. These aspects of the environment, therefore, tend to be poorly understood by the
general public.
As Scott County continues to increase in population, the demands on
groundwater resources will also increase and issues and subsequent questions regarding
groundwater quantity (supply) and groundwater quality will become more prevalent. Education
programs will be developed to provide a scientific background about groundwater and how land
use affects water resources. The intention will be to educate the public so that the issues are
understood in a factual manner and then involve the public in the solutions.
Scott County Water Resources Plan – Amendment 1
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Goals and Policies
VII.
Section 4, Page 114
Agricultural Management Goal
To reduce non-point source pollution from agricultural activities.
Reason: Agriculture, while not the only land use concern for non-point source pollution,
is practiced on a fairly large portion of the land area in Scott County. Therefore, it is
appropriate to look at this activity within its own goal and work with rural landowners to
reduce non-point sources from agricultural lands.
This includes conservation farm
planning, implementing structural conservation practices, administering a county-wide
feedlot program, using research and technology transfer to promote new farming
techniques, and utilizing the technical and financial resources of other local, state and
federal programs that encourage land stewardship.
Policies
1. Update and maintain an inventory of active feedlots.
2. Provide technical and financial assistance to operators of feedlots causing pollution
problems.
3. Offer demonstration projects using BMPs for feedlots and animal waste storage and
utilization.
4. Monitor long-term application rates of livestock wastes on land owned by feedlot operators,
as well as on land leased, rented, or volunteered for application.
5. Monitor surface and groundwater quality in feedlot areas up gradient from sensitive surface
and groundwater recharge areas.
6. Compile and publicize research data showing how to reduce non-point pollution on
agricultural land through implementing practices such as integrated pest management,
conservation cropping systems, biotechnology, manure utilization, filter strips, conservation
tillage, nutrient management, and structural erosion control methods.
7. Provide technical and financial assistance to operators of agricultural land causing non-point
source pollution problems.
8. Encourage farmers to conduct field by field soil testing to implement optimum nutrient and
pesticide application based on soil texture, organic matter, fertility levels, subsoil, and
potential for leaching.
Scott County Water Resources Plan – Amendment 1
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Goals and Policies
Section 4, Page 115
9. Provide educational materials on agricultural BMPs that reduce non-point source pollution
and maintain soil productivity and sustainable production levels.
10. Continue to participate in an annual crop residue (transect) survey to determine the level of
conservation tillage applied on cropland acres.
11. Maintain contiguous agricultural areas to preserve existing agricultural drainage systems
(private and public ditches).
12. Continue ongoing educational programs provided through the Scott SWCD, NRCS,
University of Minnesota Extension Service and other agencies that publicize and promote
land stewardship targeted at agricultural producers, rural land owners, contractors, county,
city and township staff and fertilizer dealers and distributors.
Objective 1.
Reduce soil erosion (sheet and rill, wind erosion, gully and
streambank erosion) on agricultural land to the recommended "T"
value (the maximum rate of soil erosion that will maintain a high level
of long-term crop production) or below.
Scott County has 236,784 acres within its political boundary. There are approximately 800 farms
in Scott County covering 115,000 acres. Of these farms, 100,000 acres are under till consisting
of; Corn 40,000 acres, Soybeans 35,000 acres, Alfalfa 19,000 acres, Oats/Barley 3,000 acres,
Wheat 2,000 acres and Vegetable Crops 1000 acres.
Scott County supports efforts of the Scott WMO, Scott SWCD, NRCS, University of Minnesota
Extension Service and other agencies to:
•
Target the application of conservation practices that will reduce soil erosion from greater
than "T" to "T" or less on land in the high priority sub-watersheds tributary to Minnesota
River. These include: Sand Creek, Credit River, Roberts Creek, Prior Lake/Spring Lake, and
the numerous direct unnamed tributaries of the Minnesota River.
• Contacts will be made to schedule conservation practice implementation on tracts of
agricultural land where conservation compliance plans are required. Conservation practices
will meet the requirements of state and federal programs such as: Core 4, River Friendly
Farmer, Conservation Reserve Program (CRP), Permanent Wetland Preserve Program
(PWP), Re-Invest in Minnesota (RIM), Conservation Reserve Enhancement Program
(CREP) etc. The following practice standards will be incorporated into the plans:
1. All cropland will maintain 30 percent surface residue coverage after planting, as a
rotation average.
2. Soil loss on highly erodible land is at or below the acceptable soil loss level.
Scott County Water Resources Plan – Amendment 1
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Section 4, Page 116
3. Fertilizer application rates are based on soil testing, manure testing, realistic yield
goals, and credits from previous legume crops and manure applications. Manure
handling equipment will be calibrated to insure uniform distribution of manure
applied.
4. Statewide and applicable regional BMPs for nitrogen, as recommended by the
University of Minnesota, are observed.
5. Phosphorus is banded below the surface or incorporated right after surface
application.
6. All feedlots in use are permitted by the MPCA, or in the process of being permitted,
with manure storage adequate for current needs.
7. Liquid manure is injected, or incorporated within 48 hours of surface application.
8. Within 300 feet of surface waters, drainage ditches, tile inlets, and other areas
needing special protection, manure is applied in a manner that minimizes
contamination according to MPCA guidelines.
9. Pesticides are used together with cultural pest-control practices, at no higher than
labeled rates, observing guidelines for water quality protection. Pesticide containers
are stored, handled, and disposed of in accordance with state and federal law.
10. The farm is in compliance with applicable water quality criteria.
•
Provide local, state and federal cost-share money to those landowners applying eligible high
priority practices in the high priority sub-watersheds.
•
Utilize conservation deed tax money for planning and applying soil conservation practices to
reduce erosion on agricultural land and enforcement of soil loss ordinances.
•
A comprehensive watershed planning effort will continue in sub-watersheds 3313900 and
3302900 of the Sand Creek watershed. Information gathered from this effort will be used to
prioritize practices providing the greatest reduction in sediment and nutrient delivery to
County's water resources.
•
Provide technical and administrative assistance to Minnesota Department of Agriculture for
implementing the State Revolving Fund Loan Program.
•
Educate and inform landowners, schools, units of government, special interest groups and
clubs on the various erosion control programs available to County residents.
Objective 2.
Protect, to the greatest extent possible, all surface and groundwater
resources from agricultural soil erosion, sedimentation, nutrient and
chemical contamination.
Scott County Water Resources Plan – Amendment 1
October 2007
Goals and Policies
Section 4, Page 117
Scott County supports efforts of the Scott WMO, Scott SWCD, NRCS, University of Minnesota
Extension Service and other agencies to:
•
Assist the WMO with the implementation of the Comprehensive Water Resources
Management Plan.
•
Assist with the administration of the delegated County Feedlot Program by providing
technical, financial, and feedlot permit application assistance. Assistance provided includes:
1. Administer registration programs for feedlots;
2. Locate and register all animal feedlots and manure storage areas that are currently
unregistered;
3. Distribute permit application and registration forms to owners required to make
application for a permit;
4. Review permit applications and issue construction short-form and interim permits;
5. Inspect all animal feedlots and manure storage areas in accordance with the approved
delegation agreement;
6. Review and process complaints;
7. Provide assistance to owners in completing permit applications;
8. Maintain a record of all correspondence and material relating to permit applications;
9. Submit an annual report to the MPCA by April 1 of each year;
10. Complete the required county feedlot pollution control officer training; and
11. Forward to the commissioner all permit applications, inspection reports and all other
applicable documents.
•
In cooperation with the DNR Division of Waters, maintain a network of groundwater wells
to be monitored for water level fluctuation in aquifers.
• All DNR permit applications to appropriate water or work in protected wetlands, waters or
watercourses will be reviewed for potential impacts to County resources.
• Provide financial incentive payments to landowners for establishing grass filters along
ditches, streams, wetlands, gully heads and around tile intakes.
• Complete and maintain an inventory of all ditches and streams in the County.
Objective 3.
Preserve and protect agricultural wetland areas to improve water
quality, prevent flooding and erosion from surface flows, protect fish
and wildlife habitat and promote groundwater recharge.
Scott County has 31 deep-water habitat (lakes) encompassing approximately 7,150 acres and
over 4,500 shallow water habitat wetlands (Types I - VII) covering 27,000 acres. Originally there
were over 60,000 acres of wetlands, but draining and filling activities have eliminated over 50
percent of this acreage.
Scott County Water Resources Plan – Amendment 1
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Goals and Policies
Section 4, Page 118
Scott County supports efforts of the Scott WMO, Scott SWCD, NRCS, University of Minnesota
Extension Service and other agencies to:
• Assist the 11 townships in the County with the implementation of the Wetland Conservation
Act (WCA) of 1991.
• Restore wetlands that were previously drained.
• Inventory all wetlands and altered/drained wetland basins in Scott County.
• Digitize the wetland inventory on the County GIS data base.
• Coordinate a function and value assessment of the inventoried wetlands to be used in a
comprehensive wetland management plan.
Objective 4.
Protect to the greatest possible extent existing wildlife habitat areas
and promote the development of additional wildlife habitat on
agricultural lands.
Scott County has 10,976 acres of land in Federal parks, State parks and wildlife management
areas. In addition there are 3,887 acres of regional parks, 2,908 acres in the Conservation
Reserve Program, 920 acres in the Re-Invest in Minnesota program and 300 acres in the SWCD
Filter Strip Program.
Scott County supports efforts of the Scott WMO, Scott SWCD, NRCS, University of Minnesota
Extension Service and other agencies to:
• Assist the local Pheasants Forever Chapter with the establishment of wildlife habitat.
• Work with the DNR - Forestry Division and FSA Office to make available technical and
financial assistance for developing forest management or reforestation plans.
• Make every effort possible to promote, administer and implement RIM, CRP, PWP & CREP
easements on lands within the County according to state and federal guidelines.
• Administer state sponsored conservation easement programs according to the expectation of
the legislators, Board of Water and Soil Resources and general public.
• Using USFWS grant funds, provide technical and financial assistance to Scott County
landowners in establishing native prairie grass plantings.
• Submit a grant application for cost-share assistance to establish Living Snow Fence
easements along critical snow drifting locations identified by the Scott County Highway
Department and Minnesota Department of Transportation.
• Work with the Scott County Ag Inspector/Township Weed Inspectors to control or eradicate
noxious weeds on lands within conservation easements.
Scott County Water Resources Plan – Amendment 1
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Goals and Policies
Section 4, Page 119
VIII. Flood Management Goal
To protect human life, property, and surface water systems that could be
damaged by flood events.
Reason: Proper placement of homes and structures is required to avoid damage and loss
due to flooding. This can be accomplished by understanding and managing runoff and
stormwater quantities in the County as well as providing and enforcing ordinances that
address these issues and prevent further incidents.
Policies
1. Manage local floodplain areas to maintain critical 100-year flood storage volumes.
2. Ensure that on-site or downstream detention basins are designed adequately and prevent
runoff from developed areas from negatively impacting new or existing detention basins.
3. Update floodplain zoning regulations to maintain consistency with the Scott WMO’s
Comprehensive Water Resource Management Plan, and the Vermillion River Watershed
Joint Powers Organization Watershed Plan..
4. Require that new structures be constructed above the flood-prone areas to avoid causing
an increase in the critical flood levels that could affect both the new construction and
nearby structures.
5. Maintain discharge rates and flood storage volumes to minimize pond overflow and
reduce erosion.
6. Maximize upstream storage.
7. Seek ways to increase infiltration by increasing vegetated areas and reducing impervious
areas.
8. Maintain the proper function and performance of existing stormwater conveyance
systems and storage facilities.
9. Remove accumulated sediment from storage facilities prior to reaching 50 percent of
capacity.
10. Support enhanced data sources, including updated FEMA FIRM.
Objective 1.
Manage runoff from development/redevelopment through stormwater
rate and volume control techniques and optimize site design practices
to alleviate downstream flooding.
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Section 4, Page 120
Naturally vegetated riparian areas serve a number of beneficial functions for flood control. An
undeveloped, vegetated floodplain reduces the velocity, height and volume of floodwaters by
allowing the floodwaters to spread out horizontally and relatively harmlessly across the
floodplain. Water that floods into vegetated floodplains reenters the main channel slowly,
enabling it to be stored by floodplain wetland soils and streamside forest leaf litter.
Placing impervious surfaces such as roofs and parking lots within riparian areas impairs their
capacity to detain, infiltrate and store floodwaters and runoff from adjacent uplands, and
increases the volume and speed of runoff from the riparian area into adjacent streams, resulting
in increased flooding and storm damage downstream.
Increased watershed imperviousness
typically amplifies normal streamflow patterns. Impervious surfaces result in higher peak flows
and lower base flows as stormwater, with little or no opportunity to infiltrate into the soil, can
result in direct discharges into rivers and streams. During periods of low precipitation, the lack
of pervious infiltration to groundwater reduces baseflow and causes many urbanized streams to
stagnate or dry up.
Management practices associated with stormwater runoff and downstream flooding are covered
earlier in this section as part of the Stormwater Management Goal.
Objective 2.
Cooperate with DNR to ensure that water body control structures and
outlets are maintained in good working condition.
The condition of control outlets for water bodies can have significant impacts on riparian
property and flora and fauna habitat both by flooding and low water levels. For example,
detrimental impacts from flooding can cause the following:
•
•
•
•
Excessive erosion and sedimentation;
Flooding of nesting sites;
Degradation of vegetation due to excessive water levels; and
Damage to nearby structures.
Objective 3.
Limit floodplain alteration in order to obtain “no net loss” of
floodplains, including the preservation, restoration, and management
of floodplain wetlands.
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Goals and Policies
Section 4, Page 121
Floodplain filling shall not cause a net decrease in flood storage capacity below the projected
100-year flood elevation. The proposed plan must show that, together with the filling of all other
properties on the affected waterbody to the same degree of encroachment as proposed by the
applicant, the action(s) will not cause high water or aggravate the flooding on other properties
and will not unduly restrict flood flows.
Objective 4.
Mitigate or reduce the impact of localized flooding when feasible and
ensure that structures are properly located relative to the floodplain.
In areas where localized flooding threatens public health and safety, Scott County supports
working with other jurisdictions to design and implement local and regional flood storage ponds.
New structures shall not be built within the floodway, except as accessory structures for uses
permitted in the floodway. No structure in the floodway will be allowed that will cause any
increase in the flood stage or increase in flood damages in affected reaches.
Within the flood fringe, all structures must be elevated so that lowest floor, including the
basement, is at or above the RFPE, following the specifications of Scott County’s current
ordinances or DNR standards. Railroad tracks, roads, and bridges within the floodplain will be
elevated to the RFPE where they are essential for public health, safety, and orderly functioning
where other regulatory agencies all agree. ISTS and water supply systems must be designed to
minimize infiltration of floodwaters to the system and discharges from the systems into the
floodwaters. Table 4.2 shows the standards for new building construction the Scott County. State
and Federal standards for new road and street construction with respect to flooding, freeboard
and overtopping must be followed in Scott County.
TABLE 4.2: Minimum Structure Elevations
Condition
All DNR Protected Water Bodies
and Areas Subject to Flooding.
All Other Water Bodies and
Areas Subject to Flooding.
New Building
Construction
(lowest floor elevation)
The greater of 3 feet above the
ordinary high water level (OHW)
or
1 foot above the 100-yr. Flood level
The greater of 3 feet above the
highest known water level
or
1 foot above the 100-yr. Flood level
Scott County Water Resources Plan – Amendment 1
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Goals and Policies
Objective 5.
Section 4, Page 122
Work with FEMA to complete new floodplain mapping under their
CTP program.
Scott County facilitated an aerial mapping in 2003 that included the generation of a Digital
Elevation Model (DEM) for 2-foot contours and digital ortho-photos for the entire County. The
County Surveyors Office and Natural Resources Department were the project managers for this
undertaking and worked with many partners to provide funding. The flight was completed in
spring 2003 and data was available as of fall 2003. Data from this project can be viewed on the
Scott County web site.
FEMA is leading an effort to update County floodplain maps under a CTP initiative. County
staff is working with FEMA to complete Digital Flood Insurance Rate Map (DFIRM) files for
the County. Data and maps generated from this project would be available to the public through
the County’s GIS.
IX.
Urban Development Goal
To use the County’s 2030 Comprehensive Plan Update as a guide for
development within Scott County by providing policies, objectives and
ordinances to support development while at the same time protecting and
managing the County’s water resources.
Reason:
Premature development that occurs before considerations of stormwater
management, as well as other water and natural resource management, leads to
increased environmental risk to residents and businesses and the increased cost
associated with fixing problems after the fact.
Policies
1.
The preservation, restoration, and enhancement of shoreland and wetland environments
in their natural state shall be encouraged. Where desirable and practical, developments
which complement these features and are in conformance with federal, state, and local
regulations shall be promoted.
2.
Examine requested land use changes in relation to adjoining land uses, site accessibility,
stormwater management systems availability, and consistency with the County’s 2020
Comprehensive Plan Update and policies.
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Goals and Policies
Section 4, Page 123
3.
Encourage the placement of housing units in a manner that preserves significant natural
resources.
4.
Promote compatible land use patterns on shared boundaries between urban and rural uses
as a means of protecting future urban expansion areas.
5.
Promote cooperative efforts to solve public health hazards when a hazard can be
corrected or controlled by public resources (sewer/water service, code enforcement,
inspection, sharing infrastructure costs, etc.).
6.
Establish compatible land use patterns that relate to the County's environmental features.
7.
Promote area-wide identification of environmentally sensitive natural resource areas for
guiding land use development decisions.
Objective 1.
Coordinate the implementation of the Scott County Water Resources
Management Plan with the implementation of the Scott County 2030
Comprehensive Plan Update.
The County will promote sustainable, Low Impact Development (LID) as the preferred type of
land development within the unincorporated areas of the County. Special attention will be given
to sensitive natural resource areas and projected impacts to those areas over time.
The County currently promotes LID through working with land owners and developers on a
continuous basis for the properties located within the County Planning and Zoning jurisdiction.
As part of general inquiries and the Development Review Team (DRT) meeting process, the
Natural Resource and Planning Departments routinely provide information and direction on how
to develop property in a low impact manner. In fact, as part of this preliminary process, property
owners routinely change proposed “standard” developments to a LID.
The incentives for
clustering and open space preservation contained in the Scott County Zoning Ordinance,
combined with the requirement to meet at a very preliminary stage before significant engineering
expenses are incurred, are the primary reasons LID is being promoted and implemented
regularly.
The DRT meeting process also presents an opportunity for County staff to identify potential
water resource management issues prior to a developer making a formal submittal. Department
representatives from Planning, Environmental Health, Natural Resources, Building Inspections,
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Goals and Policies
Section 4, Page 124
and Highway meet with developers and land owners to provide comments on proposed
developments in the early stages of the platting process.
Preliminary draft chapters of the 2030 Comprehensive Plan related to water resources, natural
resources, and land use are included as attachments to Appendix C. Once the update 2030
Comprehensive Plan is approved the County anticipates amending this plan to incorporate some
of the concepts included in the 2030 Comprehensive Plan.
X.
Education Goal
To inform, educate and involve individuals, groups, businesses, industry and
government in the protection and cleanup of Scott County’s water resources,
thereby increasing the understanding of water resource management and
creating a long-term commitment to improve and protect the County’s water
resources.
Reason: Educating and working with stakeholders within the WMO provides a network
of knowledgeable people that support and help carry out the goals of the Plan. Providing
an understanding of the issues and providing a forum for discussion and consensus
building regarding solutions will equate to better projects in the long run.
Policies
1. Educate key audiences, such as developers, consultants, contractors, builders and local units
of government on stormwater best management practices and erosion control measures.
2. Increase participation of property owners, developers and contractors in wetlands and
wildlife land management assistance programs, and decrease violations of wetland
regulations.
3. Encourage well water quality testing.
4. Promote a reduction in per-capita water use.
5. Provide educational materials on BMPs.
6. Conduct educational programs for homeowners, renters, grounds keepers, pesticide and
fertilizer dealers and distributors, city and county public works personnel.
7. Cooperate with ongoing educational programs by the Scott WMO, University of Minnesota
Extension Service, SWCD, NRCS and other agencies.
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Goals and Policies
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8. Help facilitate and support education/public outreach activities required under NPDES
Phase II.
Objective 1.
Implement the Education Strategy activities outlined in Appendix B.
Appendix B includes the County’s Proposed Work Plan including Educational Initiatives. The
County will review the Work Plan on an annual basis and revise as necessary. Any revisions to
the Work Plan will be submitted to the WMO for review through the Plan Amendment process
outlined in Section 5 of this Plan.
The County established an Erosion and Sediment Control (ESC) Program in 2005 to provide
inspection and enforcement of the County’s erosion and sediment control regulations as well as
the NPDES Phase II requirements. The County teams with the Scott SWCD to perform the
inspections and follow up with enforcement for any land disturbances that are not meeting
County and State requirements.
As part of the ESC Program, the County and SWCD have held workshops to provide an
overview of the ESC regulations and compliance expectations, as well as to illustrate effective
ESC practices. These workshops, which are free and open to the public, have been attended by
home builders, utility installers, landscapers, contractors, developers, and municipal staff. The
County intends to continue to hold these workshops and modify the content as may be necessary
to meet future regulation changes.
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Administration
Section 5, Page 125
Section 5
Administration
I.
Authority
The County’s surface water management authority derives from MN Statutes 103B.231
Subdivision 3 (b). The County’s groundwater management authority derives from MN Statutes
103B.255. Scott County implements its surface water and groundwater managements plans in the
unincorporated areas through its zoning authority (MN Statutes 394.21 to 394.37) and platting
authority (MN Statute Chapters 394 and 505, as may be amended). This Water Resources Plan
has been completed to meet the requirements of MN Statute 103B.235 and the Scott WMO’s
Comprehensive Water Resource Management Plan.
II.
County Board
The Scott County Board of Commissioners takes final action on all zoning requests under
County Zoning Ordinance No. 3, and on all platting requests under County Land Subdivision
Ordinance No. 7. Therefore, the County Board of Commissioners is the “governing body” of all
zoning and subdivision requirements for stormwater management, erosion control and wetland
protection in the County’s unincorporated areas. County Staff completes project reviews as well
as administrative tasks related to land development and makes recommendations to the Board of
Commissioner for planning and zoning actions.
III.
Advisory Committees
A.
County Planning Commission
The Scott County Planning Advisory Commission reviews all applications for conditional
use permits, interim use permits, land subdivisions, and zoning amendments for land in
the unincorporated areas. The County Planning Advisory Commission reports to the
County Board. The County Planning Advisory Commission is responsible for holding
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Administration
Section 5, Page 126
public hearings and reviewing all amendments to Zoning Ordinance No. 3 and Land
Subdivision Ordinance No. 7 necessary to implement this Water Resources Plan.
IV.
Staff
To administer and implement this Water Resources Plan and its goals and objectives, Scott
County will employ sufficient qualified staff under the direction of the Community Development
Director. Currently, the Scott County Natural Resources Department is preparing this Water
Plan, and will continue as the key administrative department after Plan adoption. In addition,
watershed management, due to its interdisciplinary nature, involves several County departments
and divisions, as well as the Scott SWCD.
V.
Chapter 6: Stormwater Management, Erosion Control, and
Wetlands
This Water Resources Plan will primarily be implemented through Chapter 6 of the Scott County
Zoning Ordinance No. 3. The purpose of Chapter 6 is to provide for:
1. The protection, preservation, maintenance, and use of the water and soil resources of
the unincorporated area of the County through management of stormwater drainage,
minimization of land disturbance, and prevention of damage from erosion and
sedimentation;
2. The use of controls and regulations to secure safety from floods; to prevent loss of
life, property damage, and other losses and risk associated with flood conditions; to
reduce the financial burdens imposed upon the community through rescue and relief
efforts occasioned by the occupancy or use of areas subject to periodic flooding; to
protect individual and community riparian rights; and to preserve the location,
character, and extent of natural and artificial water storage and retention areas;
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3. The enforcement of this Chapter and the coordination of the enforcement of
appropriate and applicable Federal, State, County, and local regulations;
4. The implementation of the goals and policies of the Scott County Comprehensive
Plan, as amended.
Under Chapter 6, all land disturbing activities involving ten thousand (10,000) square feet or
more of land area requires a grading permit. Grading permits are reviewed by the Planning
Department and Natural Resources Department. In most cases, grading permits are reviewed in
conjunction with a zoning or subdivision application. Depending on the size or extent of the
project, either a resource management plan or an erosion and sediment control plan is required as
part of the grading permit application.
This Water Resources Plan will require certain updates to Chapter 6 to meet the objectives of the
Plan. The goals for the updates are to achieve equivalency with Scott WMO Rules adopted on
May 10, 2005, maintain consistency with the National Pollutant Discharge Elimination System
(NPDES) Phase II requirements adopted on August 1, 2003, and preserve the quality of water
and natural resources for a growing County.
VI.
Education
Scott County has taken measures to educate property owners, home builders, developers,
contractors, realtors, and residents on the County’s stormwater management, erosion control and
wetland protection requirements. These measures include:
1. Development Review Team (DRT) Meetings – Land developers submit a sketch
plan depicting a subdivision or development proposal.
The sketch plan and
accompanying information serves as the basis for discussions between the developer,
the County’s Planning, Natural Resource, Environmental Health, Public Works, and
Building Inspection Departments, and Town Board representatives at a DRT meeting.
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This meeting is intended to provide the developer with an advisory review of the
proposal, including Chapter 6 requirements.
2. Handouts and Staff Assistance – The County Natural Resources Department Staff
is available to answer questions and assist land developers in meeting Chapter 6
requirements. Staff has prepared handout material on how to complete erosion and
sediment control plans, which is available at the community development customer
service counter or upon request.
3. ESC Workshops – The County Natural Resources Department, in conjunction with
Scott SWCD, holds workshops on the County’s erosion and sediment control
program. These workshops, which are free and open to the public, provide an
overview of ESC regulations and compliance expectations, discuss common
construction site situations, present some effective ESC practices, and give additional
resources. These workshops have been attended by home builders, utility installers,
landscapers, contractors, and developers.
VII.
Inspection, Compliance, and Enforcement
Chapter 6 includes provisions for reviewing, approving, inspecting and enforcing the County’s
stormwater management, erosion control and wetland protection requirements.
1. Review Process - All grading permits (which will require either a resource
management plan or an erosion and sediment control plan) are reviewed by the
County Planning and Natural Resources Departments to determine compliance with
the technical and performance standards of Chapter 6.
2. Financial Guarantee - Upon approval of the grading permit, the Planning
Department requires the applicant to provide a financial guarantee in the form of a
letter of credit or cash deposit in favor of the County equal to 125% of site grading
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and erosion/sediment control costs necessary to ensure the satisfactory installation,
completion, and maintenance of the measures and procedures as required in the
approved grading permit.
3. Inspection – The County has contracted with Scott SWCD to inspect an applicant’s
progress of implementing best management practices to minimize erosion and
sedimentation. If the County determines that insufficient progress or non-compliant
activity is occurring, the Planning Department notifies the applicant or landowner of
the problem and demands compliance. If compliance is not followed, the County can
draw on the financial guarantee to ensure protection of public soil and water
resources.
4. Compliance – After all of the required measures and procedures as described in the
approved grading permit have been executed to the satisfaction of the County, the
Planning Department shall issue a certificate of compliance to the applicant and
release the remaining financial guarantee. Where a resource management plan has
been approved in issuance of the grading permit, the Planning Department shall not
issue a certificate of compliance until the plan is certified as being completed by a
professional engineer.
5. Maintenance – The applicant or successors are responsible for the installation and
maintenance of any temporary or permanent measures identified in the approved
grading permit. At the time of completion of the development, those structures,
measures and systems within public easements shall be permanently maintained by
the Township after official acceptance by the Township Board.
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VIII. Public Improvement Projects
The Scott County Water Resources Plan incorporates the Scott County Highway Transportation
Improvement Program (TIP) by reference.
The current TIP dated 2005 – 2012 identifies
program goals and strategies along with a list of highway improvement projects. The projects
identified in the TIP meet the WMO’s definition for Public Improvement Projects.
IX.
Funding
There are several authorities Scott County can utilize to finance water plans, projects, and
activities. These include a variety of taxes, assessments, charges, grants, and loans. Washington
County recently conducted an in-depth Water Governance Study and did substantial research
into the tools (taxes, assessments, charges, and similar) available to fund water activities, their
appropriate use, and their advantages and disadvantages. Table 5.1 summarizes the findings in
that report. The table provides guidance in making financing decisions.
Table 5.1: Financing Options Table
FINANCE TYPE
DEFINITIONS
PROS
CONS
Special assessments
Based on ‘benefit’ and
must show a direct
increase in value or use
for property;
Difficult to use on large
area projects, but may be
applicable for smaller
local projects such as lake
flood minimization for
shore homes and property
Spreads the cost out
equally based on the tax
classification and value of
the property;
Best method to cover
administrative expenses
(bookkeeping, non-project
related studies. etc.)
Fee based on runoff
generated; If the cost to
calculate contribution is
higher than cost of the
project, stormwater utility
is not feasible;
Use only if project would
permit establishment of
special benefit to
individual parcels
Need to prove benefit to
each parcel;
Deemed least feasible for
projects to serve a broad
area;
Anticipated to be used for
isolated projects – could
not use for regional and
water quality projects
Simplest method and least
expensive to administer;
Good for overall
administration, base
funding, and small
projects
Based solely on the tax
classification and value
and the tax paid is not
related to the runoff
generated
Provides greatest
flexibility for funding
methods related to runoff;
Probably the most
equitable and do not have
to prove individual
More administration to
create a stormwater utility
and to collect funds;
Initial time spent mostly
on appeals, but then it
lightens up;
Ad valorem taxes
Stormwater
utility fee
Scott County Water Resources Plan – Amendment 1
October 2007
Administration
FINANCE TYPE
Subwatershed
assessments
Connection fees/area
charges
New water management
fee (flat fee)
Section 5, Page 131
DEFINITIONS
PROS
CONS
Watershed Authority must
make sure there is no
duplication with cities
benefit; Credits to fees
can be established based
on best management
practices; More useful for
multi-zone areas.
Costs are borne by
generators of runoff; Can
be used with ad valorem
taxes.
Not recommended for
administration financing.
Fees based on the
subwatershed the project
is located in (Credit
River, Sand Creek,
Shakopee Basin,
Southwest Scott)
Reasonable charge would
be collected from new
development that would
reduce charges to existing
properties
Setting a flat fee for all
residents and properties
(similar to Solid Waste
Fee)
Development will pay for
its costs.
Easy to administer;
Recognizes that water is
everyone’s resource;
Good for Scott County
since it covers a large area
More administrative time
to create the subwatershed
district fees associated
with each particular
project
Watersheds do not have
authority to collect;
Presently requires joint
powers agreement;
Possible challenge to fees
Not good for long-term
projects
Development of cost-share programs or partnerships when using watershed funding or applying
for additional funding through grant applications is a very important tool for watershed
programs. Where known cost share opportunities are lacking, partnerships may be developed for
cost and workload sharing and eliminating duplication of fees if possible. Scott County may be
able to share costs with cities, townships, and watershed districts, where appropriate, for program
implementation.
It is the responsibility of the County to pursue funding mechanisms for programs that
complement this Plan. The Metropolitan Surface Water Management Act (Act) allows LGUs
within the watershed management area (Scott WMO) to levy taxes (without regard to existing
levy limitations) to pay for water resource planning and management activities required under
the Act. Thus, LGU planning required to prepare or amend any plans and regulations to comply
with the Scott WMO’s management plan can be funded by new local tax levies without regard to
existing limitations on regular property tax levies within the LGU. An LGU as defined above
and under MN Statute 473.852 subd. 7 can also apply local levy over part of its jurisdiction by
creating a local drainage district for tax and planning purposes. Since Scott County is the
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planning and zoning authority for the unincorporated area in the County, the County will act as
an LGU in the unincorporated areas.
The estimated cost of adoption and enforcement of amended ordinances associated with the
adoption of the Water Resources Plan will not likely increase significant above what the County
currently spends to enforce stormwater management issues. The Planning Department currently
enforces Chapter 6 of the Zoning Ordinance which covers the majority of the rules necessary to
comply with this plan. The method of enforcement will not change.
The County has not completed an extensive search for potential grant funding for water
management projects and programs. It is likely that the County will pursue grants through the
MnDNR and other state and regional agencies. The availability of grants is related directly to
the economic stability of the area and therefore may not be a reliable funding source.
X.
Adoption, Amendment & Review Procedures
A.
Scott County Water Resources Plan Review and Adoption
The Scott County Water Resources Plan is scheduled to be adopted by the Scott
County Board of Commissioners in the Spring of 2006. This Plan will remain in
effect for five years from the date of adoption or until an amended plan is
adopted, not to exceed ten years from the date of adoption. Prior to the County
Board adoption, the Plan will be submitted to the Scott WMO and the
Metropolitan Council for review and comments, in accordance with MN Statute
103B.235, Subp. 3 and 3a.
1. Watershed Organization Review
The PLSLWD, LMRWD, Scott WMO, and the VRWJPO shall have 60 days
following submittal to complete a review of the Plan to determine consistency
with their respective Watershed Plan. The Watershed Organization shall approve
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or disapprove this Plan or parts of the Plan within 60 days. If the Watershed
Organization fails to complete its review within 60 days, the County’s Water
Resources Plan shall be deemed approved unless an extension is granted by the
County.
2. Metropolitan Council Review
The Metropolitan Council shall have 45 days to review and comment upon this
Plan or parts of the Plan with respect to consistency with the Council’s
comprehensive development guide for the metropolitan area. The Council’s 45day review period shall run concurrently with the 60-day review period by the
WMO. The Metropolitan Council shall submit its comments to the WMO and
shall also send a copy of its comments to the County. If the Metropolitan Council
fails to complete its review and make comments to the WMO within the 45-day
period, the WMO shall complete its review as provided in Minnesota Rules.
B.
Scott County Water Resources Plan Implementation
In accordance with MN Statute 103B.235, Subp. 4, the County shall adopt and
implement this Plan within 120 days from the date of approval by the WMO.
Furthermore, ordinances shall be amended, as necessary, with 180 days from the
date of approval by the WMO.
The County will notify the Watershed
Organizations regarding Plan adoption, including adoption of revised ordinances,
within 30 days, in accordance with MN Rule 8410.0170, Subp. 12.
C.
Scott County Water Resources Plan Amendments
To the extent and in the manner required by the Watershed Organizations, all
amendments to this Water Resources Plan shall be submitted to the Watershed
Organizations for review and approval in accordance with MN Statute 103B.235,
Subp. 5 and in accordance with MN Rules Chapter 8410.017, Subp. 11. This
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amendment initiated in October of 2007 constitutes the first amendment.
Additional amendments are anticipated in the next couple of years to: 1)
incorporate elements of the 2030 Comrprehensive Plan once it’s approved (draft
sections are included with this amendment in Appendix C); and 2) to incorporate
rate control standards at County boundaries in the Vermillion River Watershed
portion of the County once the VRWJPO has completed its modeling effort.
Scott County Water Resources Plan – Amendment 1
October 2007