Orcutt Community Plan EIR
5.6 Water Resources
5.6
WATER RESOURCES
5.6.1
EXISTING CONDITIONS
Statistics on the current physical status of the Santa Maria Groundwater Basin (SMGB) (i.e. the estimate of
long-term overdraft and the current basin storage level) and the supply/demand balance of the Orcutt
Planning Area have been compiled by P&D from recent reports by the Santa Barbara County Water
Agency (Ahlroth, 1992; Naftaly, 1994), the Groundwater Resources section of the County Conservation
Element and various unpublished county letters. Additional information pertaining to the State Water
Project has been provided by the City of Santa Maria and the Central Coast Water Authority.
A. Regional and OPA Setting
The California Cities Water Company (CCWC) services approximately 12,000 accounts in the Santa Maria
Valley and is the only water purveyor in the Orcutt area.
CCWC-supplied water is produced from 14 Santa Maria Groundwater Basin (SMGB) wells, and is used
for residential, commercial, industrial, and public purposes. Agricultural practices within the Orcutt area
are supplied by private, primarily non-metered wells. The total water demand on the SMGB includes
pumpage by the CCWC, the Cities of Santa Maria and Guadalupe, the Casmalia Community Service
District, and pumpage for irrigated agriculture from private wells.
Current estimates of long-term supply and demand for the Santa Maria Basin are presented in Table 5.6-1.
An average annual long-term deficit (i.e. level of groundwater overdraft) of 20,000 AFY is estimated. This
figure accounts for return flows and reports the average annual reduction of water or storage in the basin.
B. Current Water Supplies
Santa Maria Groundwater Basin: The Orcutt Planning Area currently obtains its entire water supply from
the Santa Maria Groundwater Basin. As illustrated on Table 5.6-1, groundwater pumped from this basin is
used to support various municipal industrial and agricultural uses. Agriculture accounts for most of the
pumpage of this basin, approximately 83% of the total.
The "supply" provided by the Santa Maria Groundwater Basin is equivalent to its estimated "safe yield."
Safe yield is defined as the average annual net recharge to a basin. Average annual pumpage at a level
equal to the safe yield would not result in a progressive long-term drop in basin water levels. Long-term
average pumpage which exceeds the safe yield (i.e. overdraft) will result in a gradual dewatering of a basin.
Ongoing overdraft of the Santa Maria Groundwater Basin, currently estimated to be about 20,000 AFY
(net), has resulted in a substantial reduction (300,000 AF) in the amount of water in storage over the 45year period (1935-1980) studied by the County Water Agency (Ahlroth, 1992). (Note: The County Water
Agency has stated that the actual value of basin overdraft may vary from 10,000 AFY to as much as 30,000
AFY.)
Available storage is defined as the amount of water in storage which can be pumped out of a basin before
substantial adverse environmental effects would be anticipated to occur. The effects include degradation of
water quality (e.g. salt water intrusion, concentration of dissolved solids), loss of well yield due to lowered
5.6-1
Orcutt Community Plan EIR
5.6 Water Resources
water levels, subsidence and possible loss of basin storage due to aquifer consolidation. The current
available storage in the Santa Maria Groundwater Basin (i.e. the amount of water which could be
withdrawn without significant environmental effects) is estimated to be 1,100,000 AF.
5.6-2
Orcutt Community Plan EIR
5.6 Water Resources
TABLE 5.6-1
ESTIMATED LONG-TERM SUPPLY/DEMAND BALANCE
SANTA MARIA GROUNDWATER BASIN
Gross pumpage (AFY)
Net Consumptive Use1 (AFY)
SUPPLY
118,500
83,800
12,388
6,194
City of Guadalupe
1,148
574
Cal. Cities WC (Orcutt)
8,724
6,020
SM Valley Industrial
5,400
3,726
SM Farm Homesteads
154
106
12
12
Santa Maria Basin Safe Yield
DEMAND Municipal and Industrial2
City of Santa Maria
Casmalia CSD
Subtotal M & I
27,827
16,632
97,297
67,135
33,322
22,992
130,619
90,057
TOTAL PUMPAGE
158,446
106,689
SUPPLY DEFICIT (Overdraft)
39,946
22,889
DEMAND - Agriculture3
54,600 acres (SB County)
21,090 acres (SLO County)
Subtotal Agriculture
(Rounded to 20,000 AFY net)
1
The difference between Gross Pumpage and Net Consumptive Use is the amount of pumped water that percolates back into the
basin (e.g. approximately 31% of water used for agricultural irrigation infiltrates the soil and returns to the basin).
2
From Ahlroth and Cosby (1991)
3
From Naftaly (1994)
5.6-3
Orcutt Community Plan EIR
5.6 Water Resources
Twitchell Reservoir: Since construction in 1959, Twitchell Reservoir has been an integral part of the Santa
Maria Valley water supply by capturing flows of the Cuyama River and providing a supplemental source of
groundwater recharge. Water conserved in the reservoir is released down the Santa Maria River where it
percolates into the groundwater basin. The incremental increase in recharge attributable to Twitchell
Reservoir (20,000 AFY) is incorporated into the safe yield figures for the Santa Maria Groundwater Basin
listed on Table 5.6-1.
The potential for increasing the yield of Twitchell Reservoir through modifications of the dam was
evaluated by the County Water Agency. The possibility of raising the dam by 10+ feet to allow an increase
in the "conservation" pool while maintaining the reservoir volume dedicated to flood control was analyzed.
The CWA determined that such a project was infeasible as it would not provide substantial yield above the
current method of operation of this reservoir.
Artificial Recharge Program: The Santa Barbara County Flood Control and Water Conservation District
(Flood Control) maintains a storm water drainage system in the Orcutt area which conveys runoff to a
groundwater recharge basin. This system percolates about 1,200 AFY of water into the basin. The
potential for expansion/improvement of the system is under review by Flood Control.
(Note: The 1,200 AFY figure reflects gross input of the recharge system and is somewhat greater than
actual net recharge to the basin. This is because natural recharge which would have occurred in the
absence of the system is not subtracted.)
C. Water Quality
Regional water quality trends were analyzed by the County Water Agency (Naftaly, 1994). Water quality
tends to decrease (i.e. have higher TDS) south and west of the recharge area along the Santa Maria River.
No long-term regional trend toward decreasing water quality was observed in the sparse historic water
quality data available for this study. However, an earlier study by the County Water Agency (Lawrence,
1977) states that groundwater in the Santa Maria Basin is gradually degrading in quality due to salt loading
from agricultural return flows and wastewater infiltration. The Laguna Sanitation District has been
required by the Regional Water Quality Control Board to reduce the TDS level of its treated effluent to
reduce impacts on groundwater quality (For more information see Section 5.13 - Wastewater).
D. Current Water Demand
The figures listed on Table 5.6-1 represent the most recent analysis of demand for the Santa Maria
Groundwater Basin. Gross pumpage in the Orcutt Planning Area is approximately 10,000 AFY (6% of the
total pumpage in the basin). This figure is based on California Cities Water Company demand of 8,724
AFY plus 2,100 AFY for the 1,050 acres of irrigated agriculture in the planning area.
E. Future Water Supplies
5.6-4
Orcutt Community Plan EIR
5.6 Water Resources
Changes in the supply/demand balance in the Santa Maria Groundwater Basin and in the water available in
the Orcutt area are anticipated to result from the importation of State Water and future conservation efforts,
as discussed below.
State Water Project: On June 4, 1991, voters approved the issuance of revenue bonds for the importation
of water to the SMGB through the State Water Project (SWP). The Cities of Santa Maria and Guadalupe
committed to participating in the construction of the Coastal Branch of the SWP, Phase II, an 87-mile
pipeline extending from the California Aqueduct in Kern County to the Santa Maria River.
The Coastal Branch aqueduct is "sized" (designed and built) to deliver the entitlement (not including
drought buffer) held by the various water purveyors. In order to deliver additional water (beyond about
39,000 AFY) the system would have to be operated beyond its design capacity.
The total SWP entitlement held by "participating" purveyors in the Santa Maria Groundwater Basin (City
of Santa Maria, City of Guadalupe, California Cities Water Company) is 17,250 AFY. Average annual
municipal and industrial deliveries by the SWP without major system improvements will be 79.4 percent of
entitlement in the Year 2010 according to the California Department of Water Resources (1993) assuming
that contractor requests would be at the maximum 4.2 million AFY. The Central Coast Water Authority
(CCWA) holds a "drought buffer" of 3,908 AFY in SWP entitlement proportionately shared by the CCWA
member agencies according to the amount of entitlement held by each agency. The drought buffer serves
to reduce drought period cutbacks to the CCWA and increases the long-term average annual yield of SWP
supplies held by CCWA member agencies to 87.3 % of entitlement.
California Cities Water Company (CCWC) held a 3,000 AFY entitlement and had the option to acquire an
additional 6,000 AFY of entitlement to the SWP. CCWC had intended to participate in the project at a
level of 7,900 AFY. This plan was canceled and the entitlement lost subsequent to a Public Utilities
Commission ruling that did not provide a guarantee that the CCWC would be allowed to increased
customer water rates to pay for their share of the project. As a result of recent negotiations with the Central
Coast Water Authority, CCWC has retained 500 AFY of permanent entitlement. Long-term average
annual yield of this entitlement is estimated to be 437 AFY.
State Water is expected to become available to the Santa Maria Valley in the middle of 1996. Based on the
estimated basin overdraft of 20,000 AFY (net), the delivery of State Water to the Santa Maria Valley,
primarily to the City of Santa Maria (16,200 AFY of entitlement, an estimated 14,140 AFY of average
annual yield), would substantially reduce the overall supply deficit and could alleviate a large share of the
overdraft. According to the City of Santa Maria State Water Master Plan (SWMP), approximately 4,900
AFY of entitlement (4,280 AFY of long-term yield) will be required to meet the new water demand
associated with buildout of the City's general plan. This amount assumes that the City's goal of a 20%
reduction in the historic (1980-89 average) per capita water consumption rate is achieved. Table 5.6-2
below summarizes the projections of population growth and water demand for the City of Santa Maria
(information from the SWMP).
5.6-5
Orcutt Community Plan EIR
5.6 Water Resources
TABLE 5.6-2
CITY OF SANTA MARIA
PROJECTED POPULATION AND WATER DEMAND
Year
Projected
Population
Water Demand @ 192
GPCD1
(1980-89 average use)
Water Demand @ 155
GPCD
(20% conservation)
1992
64,600
13,8902
--
2000
82,730
17,790
14,230
20103
105,662
22,720
18,180
Notes:
1.Gallons-per-capita per day.
2.Actual water use in the City of Santa Maria in 1992 was 11,925 AFY. This represented conservation of 15% from the 1980-89
average use of 192 GPCD. The 13,890 AFY figure is the estimated long-term demand of the projected 1992 population based
on a use rate of 192 GCPD.
3.Buildout of City General Plan estimated to occur in 2010.
The remaining 11,300 AFY of the City's SWP entitlement (equal to 9,860 AFY of long-term yield) would
be required for blending purposes to meet the City's water quality goals. According to the SWMP, the
City's water quality goals (maximum TDS of 500 mg/l and maximum TH of 300 mg/l) can be met during
normal operations at buildout in the year 2010.
The use of this water for blending purposes would, of necessity, involve a reduction in long-term pumpage
of the Santa Maria Groundwater Basin by the City of Santa Maria. As indicated in Table 5.6-2, existing
pumpage is approximately 13,890 AFY. If the 20% conservation goal is achieved, City demand at buildout
would be 18,180 AFY. Most of this demand (14,140 AFY) would be served by SWP supplies. Required
average annual pumpage would drop from current levels to approximately 4,040 AFY. If per capita water
consumption remains at historic levels over the long-term, City demand at buildout would be 22,720 AFY.
In this case, groundwater pumpage would be about 8,580 AFY. Thus, the City's use of State Water Project
supplies for blending would result in a long-term reduction in groundwater pumpage and basin overdraft of
5,310 to 9,850 AFY.
Conservation and Rationing: Most of the urban water conservation programs in place in the Santa
Maria/Orcutt area involve public education and direct customer contact regarding ways to use water more
efficiently.
Since 1992 over 150 urban water purveyors in the state have signed a Memorandum of Understanding
(MOU) to implement urban best management practices (BMPs). These BMPs include innovative and
intensive demand management practices. There are 16 BMPs in the MOU targeted for immediate
implementation due to their proven water savings potential.
5.6-6
Orcutt Community Plan EIR
5.6 Water Resources
The Southern California Water Company (parent company of Cal-Cities in Orcutt) has signed the MOU.
This district also adopted a Water Management Plan in August, 1994 which identifies 6 best management
practices that will be the focus of their water conservation efforts. These six practices include: ultra-low
flush toilet retrofits, residential landscape water audits, commercial/industrial water audits, in-school
education, public education and water distribution system audits and leak detection. Implementation of
these measures in the Orcutt area would result in water savings. These measures complement other
measures listed in this EIR.
To date, purveyors have not adopted restrictions or incentive programs to achieve water use reductions,
relying instead on public education and voluntary efforts by customers. There are, however, several state
mandated conservation measures (water efficient plumbing devices in new construction, water efficient
landscape design criteria for some new development) which the cities/counties must enforce. To facilitate
implementation of the MOU in Santa Barbara County, to coordinate other local efforts to promote efficient
use of water, and to eliminate duplication of efforts, the County Water Agency's regional water
conservation program includes implementation of several BMPs on a regional basis.
Continued improvement in agricultural irrigation efficiency is anticipated to result in a 5% to 10%
reduction in applied water by the year 2010 (Naftaly, 1994). Such a reduction in agricultural water use
equals a savings of 4,500 to 9,000 AFY (net).
5.6.2
THRESHOLDS OF SIGNIFICANCE
The Threshold of Significance for new groundwater extractions in the Santa Maria Basin is 25 AFY of net
new use (Groundwater Thresholds Manual, 1992). This Threshold applies to each proposal defined as a
project under the California Environmental Quality Act. Thus, it applies to individual private discretionary
projects (e.g. a lot split) as well as to the total development (buildout) allowed under the Orcutt Community
Plan. (Note: The current 25 AFY Threshold does not reflect possible reductions in long-term pumpage and
basin overdraft due to the importation of State Water by the City of Santa Maria. The Threshold would
rise to 30 AFY if these effects are considered.)
5.6.3
IMPACT ANALYSIS
A. Project Impacts; 10 Year Buildout
The 10-Year growth scenario includes the development of approximately 3,000 residential units, 500,000±
square feet of non-residential uses (commercial, office, industrial etc.) in the western part (west of U.S.
101) of the OPA. In addition, the equivalent of a 300-room hotel, one gas station and one restaurant would
be developed east of U.S. 101. Other increases in water demand likely to occur under the initiated land use
designations and programs would include construction of two new elementary and one junior high schools,
installation of 50 acres of irrigated parkland and an expansion of 80 acres of irrigated agriculture (Table
5.6-3). This new development would likely rely upon the Santa Maria Groundwater Basin for most of its
water supply. As noted above, the only currently planned and funded new water source to supply this new
development would be the State Water entitlement of 500 AFY (437 AFY net yield) currently held by Cal
Cities Water Company.
5.6-7
Orcutt Community Plan EIR
5.6 Water Resources
B. Project Impacts; Full Buildout
The initiated plan would contain approximately 6,300 new residential units (5,175 SFD; 1,000
condominium; 125 apartment), 2,300,000 square feet of new commercial/industrial space, three new
elementary schools, one new junior high school and one new high school. In addition, the equivalent of
400 hotel rooms, two gas stations and two restaurants would be developed east of U.S. 101. It is estimated
that 100 acres of irrigated park land and 160 acres of irrigated agricultural land would be developed (Table
5.6-4). This expansion of irrigated agriculture is likely to occur in the planning area on the agriculturallydesignated land east of U.S. 101. For planning purposes, it is estimated that 160 acres of strawberries
would be farmed in this area, based on the existence of such an operation on similar soils just north of the
planning area. Total buildout water demand would be 3,304 AFY. As noted above, the only currently
planned and funded new water source to supply this new development would be the State Water
entitlement of 500 AFY (437 AFY net) currently held by Cal Cities Water Company.
TABLE 5.6-3
TEN-YEAR WATER DEMAND
Type of
Development
SFD (10-R-1)
%
# units,
1000 sf
or acres
WDF
(AFY/unit)
AFY
(Gross)
AFY
(2Net)
82
2,521
.861
2,168
1,496
1
Condo
16
487
.32
156
108
Apartment
2
61
.201
12
8
Commercial
-
500
.18/10001 sf
90
62
.027
AFY/stud.
20
14
-
2
(1000
students)
.037
AFY/stud.
30
21
-
1
(1000
students)
0
.037
AFY/stud.
-
-
Elementary Schools
(Pop. 500/sch.)
Junior high school
(Pop. 1000/sch)
High school
(Pop. 1600/sch)
-
300-room hotel
-
96.98
.4/10001 sf
39
27
1 gas station
-
2
.33/10001 sf
1
1
1 restaurant
-
3
.53/10001 sf
2
1
Irrigated park land
-
50 acres
2.7 AFY/ac6
135
93
-
200 acres
2.68
AFY/ac4
-537
-370
Subtotal =
2,116
1,461
3
Demand reduction
due to agricultural
conversion
5.6-8
Orcutt Community Plan EIR
5.6 Water Resources
Increased
irrigated
agriculture
-
80 acres
5.6-9
2.7 AFY/ac5
216
149
Total =
2,332
1,610
Orcutt Community Plan EIR
5.6 Water Resources
TABLE 5.6-4
BUILDOUT WATER DEMAND
Type of
Development
%
# units,
1000 sf
or acres
WDF
(AFY/unit)
AFY
(Gross)
AFY
(2Net)
SFD (10-R-1)
82
5,175
.861
4,450
3,071
Condo
16
1,000
.321
320
221
Apartment
2
125
.201
25
17
Commercial
-
2,300
.18/10001 sf
414
286
.027
AFY/stud.
30
21
-
3
(1500
students)
.037
AFY/stud.
30
21
-
1
(1000
students)
High school
(Pop. 1600/sch)
.037
AFY/stud.
48
33
-
1
(1600
students)
400-room hotel
-
129.28
.4/10001 sf
52
36
2 gas station
-
4
.33/10001 sf
1
1
2 restaurant
-
6
.53/10001 sf
3
2
Irrigated park land
-
100 acres
2.7 AFY/ac6
270
186
-
481 acres
2.68
AFY/ac4
-1,289
-889
Subtotal =
4,354
3,006
2.7 AFY/ac5
432
298
Total =
4,786
3,304
Elementary Schools
(Pop. 500/sch.)
Junior high school
(Pop. 1000/sch)
3
Demand reduction
due to agricultural
conversion
Increased
irrigated
agriculture
-
160 acres
Notes for Tables 5.6-3 and 5.6-4:
1
Water Duty Factors (WDF) from 1992 Groundwater Thresholds Manual.
2
Return flows at 31%
3
Approximately 481 acres of irrigated agriculture on Key Site #22 would be converted to non-agricultural uses. The irrigated agriculture
includes 20 acres of row crops and 380 acres of strawberries.
4
Water duty factor is a composite of the value for strawberries (2.7 AFY/ac) and the value for row crops (2.4 AFY/ac) provided by the
Farm Advisor (1991).
5
Water duty factor is the value for strawberries (2.7 AFY/ac) provided by the Farm Advisor (1991).
6
Water duty factor is the value for turfgrass (2.7 AFY/ac) provided by the Farm Advisor (1991).
5.6-10
Orcutt Community Plan EIR
5.6 Water Resources
7
Water duty factor for schools from the City of Santa Barbara Water Demand Factor and Conservation Study "Technical Report"
(1989).
8
Square footage based on 323 sf/room factor from Pacifica Suites Hotel in Goleta.
Impact Summary
Impact WAT-1: Increased overdraft by 2006. Residential, commercial-industrial, municipal and
agricultural growth within the Orcutt Planning Area projected to occur over the next ten years would create
potentially significant impacts to groundwater resources as this growth would contribute substantially to
ongoing and increased overdraft of the Santa Maria Groundwater Basin by generating an increase in net
water demand of 1,610 AFY.
Impact WAT-2: Increased overdraft at buildout. Residential, commercial-industrial, municipal and
agricultural growth within the Orcutt Planning Area permitted under buildout of the proposed Community
Plan would create potentially significant impacts to groundwater resources as this growth would contribute
substantially to ongoing and increased overdraft of the Santa Maria Groundwater Basin by generating an
increase in net water demand of 3,304 AFY.
C. Cumulative Impacts
Additional water demand would occur with population growth in the Santa Maria Valley at buildout of the
Orcutt area. Water demand associated with buildout of the City of Santa Maria's General Plan and the
Santa Maria Public Airport Master Plan (draft specific plan currently under development), however, is
anticipated to be met by the State Water Project supplies anticipated to be available in 1996. The City of
Santa Maria holds a SWP entitlement of 16,200 AFY which represents a long-term average annual yield of
14,140 AFY. The potential increase in groundwater pumpage above current levels due to the Orcutt
Community Plan would represent a cumulatively significant impact as it would constitute a substantial
contribution to ongoing overdraft of the basin.
5.6.4 MITIGATION MEASURES
As detailed in the previous section, several thousand acre-feet per year (AFY) of water would be needed to
support buildout of the Orcutt area. Three basic options for obtaining this water are available and include
continued (increased) overdraft of the Santa Maria Groundwater Basin, the use or development of new
supplemental supplies and water conservation. Long-term or permanent reliance upon increased overdraft
to support community buildout is not considered sound planning. Thus, the following discussion is limited
to currently available supplemental sources of water, the options for the development of new supplies and
conservation as mitigation for the buildout proposed under the plan. Both short-term and long-term supply
needs are addressed below.
A. Water Supply Options
Short-Term Supply: For a limited time period, support of some growth through continued pumpage of the
Santa Maria Groundwater Basin could be done with only minor effects on the basin due to the large
amount of water in storage (1,100,000 AF). This would be appropriate on a planning basis only if this
5.6-11
Orcutt Community Plan EIR
5.6 Water Resources
action were combined with implementation of a supplemental water supply project with a specific
timetable for the arrival of new supplies.
Many water purveyors in Santa Barbara County, including those in the Santa Maria Valley, are
participating in the Coastal Branch Aqueduct and Santa Ynez Extension pipeline projects which will
deliver State Water to Santa Barbara County. The total annual amount of water (AFY) held by contract by
the various agencies is more than they are likely to need for the next ten to fifteen years. It is anticipated by
the County Water Agency that substantial amounts of surplus State Water would be available for purchase
for at least the next decade. It is anticipated that the water purveyor in the Orcutt area would be able during
this interim period to purchase sufficient amounts of this water to support growth in the Orcutt area. In fact,
it would be possible during this period for the local purveyor to bank (store for future use) purchased State
Water in the Santa Maria Basin. However, as growth occurs in the service areas of the various water
purveyors, the amount of available surplus State Water would progressively drop and eventually reach zero.
(Note: The California Cities Water Company holds a permanent entitlement to 500 AFY of State Water
which represents an estimated long-term yield of 437 AFY.)
Although short-term supplies would likely be available, a long-term or permanent source of supply would
need to be developed to support the buildout of the community plan.
Long-Term Supply: A number of options for developing new supplies are discussed at the end of this
section. These options vary greatly in terms of cost, the amount of potential new supply and the level of
constraints on implementation. Because of high implementation costs, some of the options may not be
considered feasible as mitigation for the water supply impacts of the Orcutt Community Plan. Refer to the
Potential New Water Supply section below.
Presented below is an example water management program that combines elements of the various supply
options with the intent of providing adequate mitigation at the lowest cost.
Example Water Supply Program:
Currently available new supplemental supply: The California Cities Water Company holds a permanent
entitlement to 500 AFY of State Water which represents an estimated long-term yield of 437 AFY.
This 437 AFY is considered to partially offset the new demand associated with the proposed
community plan.
Comment: Implementation of this supply would reduce the increase in overdraft due to full buildout to
2,867 AFY (2,569 AFY for urban uses only).
Conservation - proposed new single family dwellings: As outlined in Table 5.6-43, buildout of the Orcutt
Community Plan would require an estimated 3,304 AFY (net). The 3,071 AFY (net) water demand
of the proposed 5,175 single family dwellings is the majority of the project demand. If the .86 AFY
average water use estimated per unit (i.e. the water duty factor) could be reduced through the
enactment of required active conservation measures, the demand of the community plan project
could be substantially reduced.
5.6-12
Orcutt Community Plan EIR
5.6 Water Resources
The .86 AFY water duty factor (WDF) is based on actual metered water use for newer homes in the Orcutt
area. It is assumed that these homes were built with low-flow interior plumbing fixtures (e.g. 1.6 or
3.5 gallon/flush toilets). Thus, in terms of interior water use, this factor is representative of future
construction in the planning area under existing plumbing codes and ordinances. Based on an
average of 2.87 persons in the average detached home and the .06 AFY/person factor for interior
water use in the Groundwater Thresholds Manual (1992), interior water use per SFD would be .17
AFY. Thus, exterior water demand would be .69 AFY/SFD.
Mitigation "credit" for water-conserving landscape design is not generally applied in environmental review
of individual projects because it is not feasible to monitor and enforce landscape and irrigation
restrictions in perpetuity. However, a water-conserving landscape design requirement applied as a
policy over the proposed new SFD developments in the Orcutt Community Plan would result in
water savings. Water-efficient landscaping, limitations on turf, efficient watering techniques and
other measures (listed below), could reduce landscape irrigation water use in the early years of
occupancy by approximately 20% according to the County Water Agency. Over the long-term, the
average efficiency of irrigation systems tends to drop and the landscaping could become less waterefficient due to inconsistent system maintenance and higher water demand replacement plantings.
However, a meaningful proportion of the homes initially built with water-conserving landscape
design would continue to use less water. For planning purposes, it is assumed that the waterconserving measures installed in new homes would remain in operation over the long-term in the
equivalent of 30% of the proposed SFD's. Water savings would be approximately 147 AFY (5,175
units x .69 AFY x .20 x .30 = 214 AFY gross x .69 = 147 AFY net).
The following list contains ideas that could be included in a landscape design requirement implemented by
the County or local water purveyor to attain the 20% reduction goal.
•
•
•
•
•
•
•
•
•
•
•
Limit turf area to no more than 25% of landscaped area
Require appropriate turf types - warm season grasses
Require drip irrigation or micro-sprayers on appropriate shrub areas
Require devices like soil monitors and rain shutoff devices for all automatic irrigation systems.
Provide training and advise in how to use these systems properly.
Provide information about efficient watering techniques (especially in sandy soil) and how to use
weather information to schedule irrigations (there is a weather monitoring station in the
Santa Maria area).
Distribute information brochures on design (plants, irrigation systems) and irrigation techniques to
homebuyers.
Recommend or require a home water survey every 5 years to check irrigation efficiency.
Encourage or require mulch in non-turf areas.
Encourage permeable hardscape.
Encourage use of soil amendments to increase soil moisture holding capacity of soil
Work with water purveyors and landscape industry to provide ongoing education. Refer to previous
discussion regarding the MOU signed by Southern California Water Company (Cal-Cities).
Comment: When combined with existing State water entitlements, this "supply" would reduce total net
increases in overdraft to 2,720 AFY or 2,422 AFY for urban uses only.
5.6-13
Orcutt Community Plan EIR
5.6 Water Resources
Conservation - existing residential units: An active retrofit program to replace high-flow (5.5 gallon/flush)
toilets in existing older homes with low-flow (1.6 gallon/flush) toilets would result in long-term
water savings. The potential savings are calculated as follows:
•
It is assumed that approximately two-thirds of the existing 11,000 residential units in the Orcutt
Planning Area have high-flow toilets and that 70% of those would be converted to low-flow
toilets.
•
The annual per person water savings from a conversion from a 5.5 to a 1.6 gal/flush is 5694 gallons
(Groundwater Thresholds Manual, 1992).
•
The average population per residential unit is 2.87 (figure for all units; 1994 Housing Element).
•
Wastewater return flows are estimated to be 31%.
[(11,000 units x .667 x .70 x 2.87 x 5,694 gal.) ÷ 325,851 gal./ac-ft = 257 AFY gross, 177 AFY net]
As shown above, a water savings of 177 AFY (net) is possible with a toilet retrofit program.
Comment: When combined with existing State Water entitlements and landscape conservation in new
development, this "supply" would reduce the total net increase in overdraft to 2,543 AFY or 2,245
AFY for urban uses only.
Summary: Approximately 761 net AFY would be saved with implementation of the above measures (and
State Water). The 761 AFY would represent about 23% of the new demand associated with the proposed
community plan. An estimated 2,543 AFY of total net new water demand would remain. Of the 2,543
AFY of net new demand, 2,245 AFY would be due to potential urban development (298 net AFY for
future agricultural expansion in the planning area is included in the demand figures as CEQA requires a
ground-to-plan analysis).
Purchase and retirement of Irrigated Agricultural Land: As discussed in a later section, the
purchase and retirement of historically irrigated agricultural land is a technically feasible option to
mitigate the new water demand associated with the proposed community plan. To offset the
remaining 2,245 AFY of net new urban demand under the proposed community plan, the purchase
and retirement from irrigation of 1,352 acres of land would be required (based on an average net
water duty factor of 1.66 AFY/acre). This option is likely to be the most cost effective, currently
available method to provide for mitigation for the impacts of urban development associated with
the Orcutt Community Plan. Other large-supply options, such as construction of a seawater
desalination plant, would be more costly (see discussion below).
Retirement of such a large area of irrigated land would constitute a significant adverse impact on
agriculture in the Santa Maria Valley. Furthermore, it is possible that some of the agricultural
operation displaced by such a land purchase would be transferred to another location in the basin.
Pumpage at the new location would offset some of the water savings of the land purchase. Other
supply options are discussed in the following section.
5.6-14
Orcutt Community Plan EIR
5.6 Water Resources
Funding for Water Supply Program: A likely source of funding for the above mitigation measures
would be a development fee placed on new units built under the proposed Community Plan. It is
likely the such a fee would be on the order of a few thousand dollars per unit. A detailed analysis of
potential fees for the above example program has not been prepared. Note that the cost for the
desalination option (analyzed below) ranges from $2,300 to $9,900 per dwelling unit.
B. Other Potential Long-term Supply Options
State Water Project: CCWC has retained 500 AFY of permanent entitlement to the State Water Project.
Long-term yield of this entitlement is estimated to be 437 AFY and represents new supplemental supplies
available to the Orcutt area. This amount of water represents about 13% of the supply needed to support
buildout of the Community Plan. (Note: The details of the community plan have not been determined by
the decision-makers but is assumed here to involve approximately the buildout water net demand of 3,304
AFY discussed previously). Thus, additional long-term supplies would be required to support buildout.
It is possible that additional permanent entitlement could be purchased from the City of Santa Maria or
"downstream" (i.e. south of the Santa Maria Valley) State Water Project contractors in Santa Barbara
County. The potential for additional purchases of SWP entitlement should continue to be explored as this
source could readily be added to the community's water supply at a price comparable or less than other
sources. Note that purchases could involve sales of entitlement in which deliveries are interrupted in the
event of drought conditions.
Desalinated Seawater: Construction of a ocean water desalination facility in the Santa Maria Valley is
technically feasible and could provide a long-term source of water sufficient to support buildout of the
Orcutt Community Plan. The key issue with such a facility is how much would it cost and how would this
cost be paid. A preliminary analysis of the financing of this option has been prepared (Baca, October
1994).
A desalination facility with a 3,500 AFY capacity is estimated to cost, in 1995 dollars, $27,300,000 (based
on a California Department of Water Resources estimate for a 10,150 AFY facility). This figure represents
the capital cost of facilities and does not include operation and maintenance (O&M). The cost of this
facility would escalate to $35,900,000 by the year 2005 based on U.S. Bureau of Reclamation construction
cost index trends.
For purposes of analysis the following assumptions are made:
1.
It is assumed that all capital costs would be paid through a development fee paid upon the building
of each new unit authorized under the Community Plan.
2.
The O&M costs would be paid by each consumer in the Orcutt area as part of unit water charges.
(The per acre-foot meter charge of desalinated water is not analyzed in this preliminary analysis.)
3.
The buildout of the Community Plan would occur in 20 years (i.e. be accomplished by the year
2015).
5.6-15
Orcutt Community Plan EIR
5.6 Water Resources
4.
The desalination facility would be built in the year 2005 after approximately one half of buildout
had occurred.
5.
Development fees would be collected for a twenty-year period (1995-2015) and placed in a
dedicated water fund.
6.
The interest rate earned on the water fund balance would be 4.0 percent and the interest rate paid on
the loan (bonds) for the desalination plant would be 6.0 percent.
7.
Development fees would be collected for each new unit in proportion to the estimated water use of
that type of unit.
8.
The desalination plant would be financed for a period of ten years with payments made from the
water fund. The balance of the fund and the remaining debt on the facility would reach zero
simultaneously at buildout in the year 2015.
Given the above assumptions, the development fees which would be collected from new units to fund the
capital costs of a desalination plant would be approximately as follows:
SFD
Condo
Apartment
1000 sf Commercial
$9,900
$3,700
$2,300
$2,100
These numbers are very preliminary and depend greatly on the numerous assumptions listed above. For
example, the development fee on new units would be substantially reduced if the capital costs were funded
by the whole of the Orcutt area through meter charges. Note that the Orcutt area as a whole would benefit
from the new supply source in terms of water quality. First, desalinated water would be of better quality
that existing groundwater. Second, a desalination facility could be designed such that wastewater from the
Orcutt area could be discharged to the ocean with the brine produced in the desalination process. This
would address regional water quality degradation due to wastewater return flows. Note, however, that
ocean discharge would eliminate these return flows as a source of recharge to the groundwater basin.
(Note that construction of a new desalination facility in the Santa Maria Valley is technically unnecessary
because the existing City of Santa Barbara desalination plant is effectively connected to the Orcutt area
through the State Water Project pipeline. Refer to the discussion in this document on purchase of out-ofbasin supplies.)
Artificial Recharge:
Urban Area Recharge Improvements: Flood Control maintains a storm water drainage system in the Orcutt
area which conveys runoff to a groundwater recharge basin. This system percolates about 1,200 AFY of
water from the Orcutt area and portions of the City of Santa Maria into the basin. There is some potential
for expansion/improvement of this system as part of the development of the Orcutt area. However, much
of the area to be developed is already part of the system or at an elevation or a location which would
preclude connection to the system. It is not anticipated that a substantial portion of buildout demand can be
5.6-16
Orcutt Community Plan EIR
5.6 Water Resources
met through expansion of this system. The potential yield of such an expansion is roughly estimated by the
County Water Agency to be no more than a few hundred AFY. System improvements are currently under
analysis by the Santa Barbara County Water Resources Division.
Santa Maria River Recharge Basins: Another recharge project has recently been proposed on the Santa
Maria River by the Coast Rock mining company. The Coast Rock project includes the construction of a
recharge basin in the Santa Maria River bed (i.e. a hole left after mining). Based on recent review of the
project by County Planning and Development and the County Water Agency (Baca and Ahlroth, personal
communication) this project would not have the potential to substantially increase basin yield. If several
significant operational constraints (such as long-term basin maintenance) could be overcome, maximum
potential increases in basin yield through these facilities would be only a few hundred AFY. A recharge
basin adjacent to the Santa Maria River is not considered a feasible water supply option.
Orcutt Creek Stream Diversion: The County Water Agency and a consultant (Penfield and Smith) are
currently analyzing the feasibility, cost and potential yield of a stream diversion and associated artificial
recharge system constructed on or adjacent to Orcutt Creek. Based on preliminary analysis by the County
Water Agency, it is estimated that long-term yield of such a system would be a maximum of about 300
AFY, assuming a maximum 6.7 cubic-feet/second diversion rate and a 40 acre-foot capacity reservoir.
Enhanced Sisquoc River Recharge Project: This potential water supply project involves pumpage of
groundwater along the Sisquoc River to lower water levels to enhance recharge during periods of high
flows along the river. The pumped water would be delivered to current water users and would reduce
pumpage by an equal amount in other areas of the basin further to the west. This project was recently
analyzed by Penfield and Smith Engineers under the direction of the County Water Agency. This project
was determined to be infeasible due to substantial operational constraints related to the wide variation in
flow rates of the Sisquoc River.
New Reservoirs: Of the 14 possible reservoir sites studied in the 1950's by the US Bureau of Reclamation,
the "Round Corral" site is the most feasible option (Naftaly, 1994). The dam would be located near Round
Corral Canyon on the Sisquoc River. This facility would have a yield of 5,500 to 6,700 AFY and cost
about $100 million. Given the high cost, the low likelihood of regulatory approval of a major new dam
project and the relatively-low yield of this potential facility for a major surface reservoir, this option is not
considered feasible as a potential supply for the Orcutt area.
Wastewater Reclamation: Because wastewater in the Santa Maria Valley is not discharged to the ocean,
the potential for saving water is limited. If the land now irrigated with effluent from the Laguna Sanitation
District were permanently taken out of irrigated agriculture concurrent with treatment and reuse of
wastewater, some quantity savings could be achieved. However, the regulatory constraints on the use of
reclaimed water would prevent use of this water for much of the existing or proposed development in the
Orcutt area.
The primary benefit of treatment of wastewater would be an improvement of water quality in the
groundwater basin. Treated (reclaimed) effluent would have a lower TDS than existing wastewater and
would degrade groundwater to a lesser degree upon its ultimate percolation back into the basin.
5.6-17
Orcutt Community Plan EIR
5.6 Water Resources
Cloud Seeding: Cloud seeding is an effective method of increasing rainfall and associated yield of surface
reservoirs and groundwater basins. The Santa Barbara County Water Agency currently operates a cloud
seeding program in the watershed upstream of the Santa Maria Groundwater Basin. This program currently
yields an estimated yield of 3,500 AFY. Although an effective program, cloud seeding cannot be
considered a potential supply for the Orcutt area because it is an existing supply and part of the calculation
of basin overdraft. The yield obtained cannot be assigned to the Orcutt area as it is obtained through
operation of the Twitchell Reservoir. This reservoir is funded through an assessment district located
outside of the Orcutt area. Furthermore, this program is currently operated at the maximum regulatory
level allowed under rules designed to minimize flood hazards.
Water Conservation: The potential for water savings for existing municipal and industrial uses in the
Orcutt area is difficult to precisely determine. Recent local and State laws have been created to require
more efficient use of water. According to Naftaly (1994), municipal water use could be reduced by up to
20 percent with aggressive conservation efforts. It would be difficult to implement, and enforce
compliance with, most "aggressive" conservation measures involving existing homes and businesses.
Implementation of rate structures designed to reduce water use (i.e. punitive water rates for high use) also
cannot be assured. The results of these conservation efforts cannot be accurately quantified in advance.
One simple program involving existing homes, toilet retrofit, is feasible and would result in some water
savings. As analyzed in the example water supply program above, about 177 AFY of water can be saved
through a toilet retrofit program in the Orcutt area.
Water could be conserved through mandated water-conserving landscape design incorporated into new
units constructed under the Orcutt Community Plan as discussed above in the example water supply
program. New demand of the Plan could be reduced by 147 AFY.
As discussed previously, the Southern California Water Company (parent company of Cal-Cities in Orcutt)
has signed the statewide MOU on water conservation and has adopted a Water Management Plan which
identifies 6 best management practices that will be the focus of their water conservation efforts.
Implementation of these measures in the Orcutt area would result in water savings.
Agricultural water conservation could save substantial quantities of water as previously stated (4,500 to
9,000 AFY). Ongoing improvements in irrigation technology has reduced per acre water use on many
crops. Future advances in technology will likely contribute to this trend. Such water savings would not be
of the magnitude to eliminate the overdraft of the Santa Maria Basin. In any event, such water savings
would not be related to urban development in the Orcutt area and could not be "assigned" to the Orcutt area
for buildout of the community plan.
Purchase and Retirement of Irrigated Agricultural Lands: The potential increase in groundwater
overdraft due to buildout of the Orcutt Community Plan could be offset by a reduction in groundwater
pumpage by the purchase and retirement of existing irrigated crop land. Given the *3,006 AFY (net) urban
demand of the plan and an average agricultural water duty factor of 2.4 AFY/acre (gross) or 1.66 AFY/acre
(net) for the Santa Maria Valley (CWA, Ahlroth; person. comm.), the purchase and elimination of
irrigation on about 1,811 acres of land would be required to fully offset the impact of the proposed
community plan. This total acreage figure assumes that none of the agricultural operation displaced by a
land purchase would be transferred to another location in the basin. Such a transfer is possible. Pumpage at
5.6-18
Orcutt Community Plan EIR
5.6 Water Resources
the new location would offset some of the water savings of the land purchase. While technically feasible, a
land purchase program would likely have significant impacts on agriculture in the Santa Maria Valley.
*
(Note: The 3,006 AFY net demand shown on Table 5.6-4 does not include the 298 AFY for future
agricultural expansion in the planning area. This 298 AFY is included in the demand figures for the
Orcutt Community Plan because CEQA requires a ground-to-plan analysis. The 298 AFY is not included
in this discussion as it would not make sense to retire currently-irrigated land as mitigation for potential
future agriculture.)
Purchase of Out-of-basin Permanent Supplemental Supplies
Because the Orcutt area is connected to the State Water Project through the Central Coast Water Authority
pipeline, it is possible for the local water purveyor to purchase, and have delivered, permanent
supplemental water supplies (i.e. supplies other than SWP entitlement) produced in other parts of State to
support the proposed growth under the Orcutt Community Plan. The supplemental water would not be
physically delivered to the Orcutt area but would be transferred in the form of a credit for an amount of
State Water. Supplemental water produced elsewhere could be delivered to a nearby State Water
contractor and the equivalent amount of water would be drawn from the SWP pipeline in Orcutt. Such a
water supply program would mainly be limited to arrangements with downstream water purveyors due to
the limits on CCWA pipeline capacity.
An example of such a program would involve the utilization of the existing City of Santa Barbara seawater
desalination plant. The water purveyor in Orcutt (currently CCWC) could enter into a contract with the
City of Santa Barbara to purchase 2,500 AFY (or other amount) of water produced at the desalination plant
on a permanent basis (i.e. the Orcutt area would have a permanent right to use a portion of the plant's
capacity). The desalinated water would be physically delivered to the City of Santa Barbara water
distribution system for City use. An equal amount of State Water owned by the City (or owned by other
South Coast water purveyors linked to the City through the Cachuma project) would be drawn from the
CCWA pipeline through the turnout located in Orcutt and delivered to customers in the Orcutt area. The
contract would likely be structured such that the City and other South Coast purveyors would have the full
use of the plant in the event of a critical drought. During these critical drought periods, water users in the
Orcutt area would be served entirely through pumpage of the Santa Maria Groundwater Basin. This
arrangement could be implemented with no physical improvements. Note that the physical operation of the
desalination plant would not likely occur for many years due to the anticipated availability of surplus State
Water.
An out-of-basin purchase of supplemental water supply, such as the above example, is technically feasible
to fully mitigate the new water demand associated with buildout under the Orcutt Community Plan. It
would, however, require the local water purveyor to enter into a supply contract and commit to limiting its
average annual groundwater pumpage to the historic level of pumpage by that purveyor.
Summary of Supply Options
The following supply options are discussed in the previous section:
5.6-19
Orcutt Community Plan EIR
5.6 Water Resources
State Water Project
Desalinated Seawater
Artificial Recharge:
Urban Area Recharge Improvements
Santa Maria River Recharge Basins
Orcutt Creek Stream Diversion
Enhanced Sisquoc River Recharge Project
New Reservoirs
Wastewater Reclamation
Cloud Seeding
Water Conservation
Purchase and Retirement of Irrigated Agricultural Lands
Purchase of Out-of-basin Permanent Supplemental Supplies
Based on the analysis presented in previous sections, the most feasible options for mitigation of the
estimated new long-term water demand associated with the proposed Orcutt Community Plan are water
conservation, purchase and retirement of irrigated agricultural lands, construction of a seawater desalination
plant and the purchase of out-of-basin supplemental supplies.
C. Specific Mitigation Measures
Mitigation WAT-1: All new development within the Orcutt Planning Area shall pay fees sufficient to
offset its increased water demand, including the costs of planning and implementation of new conservation
/ water supply projects. (addresses Impacts WAT-1 and 2)
Mitigation WAT-2: The County shall actively pursue the formation of a Community Services District or
other special district encompassing the Orcutt Planning Area in order to provide for public control of the
planning and implementation of new water supply and conservation measures for the community.
(addresses Impacts WAT-1 and 2)
Mitigation WAT-3: The County shall encourage the California Cities Water Company to obtain
additional permanent entitlement to the State Water Project or other out-of-basin supplemental water
supply through long-term exchange agreement if such supplies become available. (addresses Impacts WAT1 and 2)
Mitigation WAT-4: The County shall require that the maximum feasible water conservation measures be
included in all new development projects. (Specific conservation measures are listed in the Example Water
Supply Program discussed above). (addresses Impacts WAT-1 and 2)
5.6.5
RESIDUAL IMPACTS
The combination of municipal water conservation measures (Mitigation WAT-4) and the State Water
entitlement held by California Cities Water Company is considered feasible to mitigate (offset) about 23%
of the new water demand. While fees can be collected (Mitigation WAT-1) and a Community Services
District formed (Mitigation WAT-2), implementation of new supplemental supply options (Mitigation
5.6-20
Orcutt Community Plan EIR
5.6 Water Resources
WAT-3) cannot, in general, be assured. With one exception, the complexity, high cost, potential
environmental constraints and other uncertainties surrounding major water supply projects would render
the identified supply options infeasible as effective mitigation. The one exception is the option of purchase
of out-of-basin permanent supplemental supplies. As indicated in the example involving the City of Santa
Barbara desalination facility, such a program could be accomplished through contractual arrangements
without the construction of new facilities. In order for this supply option to be considered feasible
mitigation, however, a firm commitment by the water purveyor in the Orcutt area and the various other
involved water purveyors and agencies would be required.
Based on the above discussion, residual impacts on groundwater resources would be considered:
Significant and Unavoidable (Class I) if no firm commitment had been made by the involved water
purveyors and agencies to purchase out-of-basin permanent supplemental supplies to offset the new
demand associated with buildout under the Orcutt Community Plan, or
Potentially Significant but Subject to Effective Mitigation (Class II) if a firm commitment had been
made by the involved water purveyors and agencies to purchase out-of-basin permanent supplemental
supplies to offset the new demand associated with buildout under the Orcutt Community Plan.
5.6-21