Developing an Ecological Risk Ranking System for Phosphorus for the Lake Champlain Basin
Alison Foster, Scott Ritter, and Alex Arntsen
Problem Statement:
Phosphorus from non-point and point sources contributes nutrient loading in Lake
Champlain and its tributaries, which can lead to eutrophication.
Goal/ Purpose Statement:
To categorize risks of sources of phosphorus to the health of Lake Champlain Basin by
examining the volume discharged and its effect on aquatic organisms and their habitats. This
information can be used to identify appropriate allocation of funds and resources to decrease
phosphorus inputs to the lake.
Justification:
Increased phosphorus loading from non-point and point sources into tributaries of Lake
Champlain has caused increased levels of the nutrient within the lake. The primary issue related
to increased phosphorus is the eutrophication within Lake Champlain, which has caused
significant algal blooms in some bays. As a result of these blooms beaches become unsafe and
unattractive for recreation as the water develops slime from toxic varieties of cyanobateria.
When the algae dies and begins to decay it results in a reduction of available oxygen forcing fish
to utilize other habitats. There is also some evidence of accumulation of toxins in fish species
that feed on the algae. Should these effects of increased phosphorus load not be dealt with
tourism, fisheries, and safe recreation will be severely impacted.
A wealth of benefits are stood to be gained should phosphorus levels diminish
ecologically, economically, and culturally. Lake Champlain is an icon of both Vermont and New
York, and is an established and popular tourist destination. Reducing algal blooms and creating
healthy ecosystems for fish will be advantageous to recreational and sport fishing communities,
along with supporting diversity and abundance of aquatic organisms. The shores of the lake are
also frequently used for recreation as well, and allow for the use of Lake Champlain’s beaches.
Ensuring that waters are swimmable is important to the economic income of the region as
beaches are a very large source of summer tourism and recreation for the state.
Literature Review:
(2007). GIS map of current stormwater permits in Vermont. Vermont Agency of Natural
Resources Department of Environmental Conservation
http://www.anr.state.vt.us/dec/waterq/stormwater/htm/sw_permitviewer.htm
This source will be used to identify areas of high stormwater runoff and the amount of runoff
that should be coming from these areas.
Stormwater Interactive Map. New York Department of Environmental Conservation.
http://www.dec.ny.gov/imsmaps/stormwater/viewer.htm.
Same function as above.
(2007). List of Vermont stormwater impaired areas. Vermont Agency of Natural
Resources.
http://www.anr.state.vt.us/dec/waterq/stormwater/htm/sw_impairedwaters.htm
The above lists watersheds that have been listed as “impaired” as a result of by stormwater and
fail to meet Vermont Water Quality Standards, including a list of the permitted discharges. This
information will be used in conjunction with the map above to further identify the major sources
of stormwater runoff.
(2002). Lake Champlain Phosphorus Total Maximum Daily Load (TMDL). Vermont Agency
of Natural Resources and New York State Department of Environmental
Conservation.
Although the current TMDL was rejected, it still contains valuable information about the sources
of phosphorus in the lake and research regarding what areas and sources in the lake need the
most attention.
Watzin, et. al. (2005). Ecosystem Indicators and an Environmental Score Card for the
Lake Champlain Basin Program. Lake Champlain Basin Program. 46.
This source describes several indicators relevant to a pressure-state-model representation of
phosphorus loading in Lake Champlain. Sources of phosphorous are explained, as are the
impacts of phosphorous within the lake.
Gaddis, E. B., H. H. Falk, C. Ginger, and A. Vionov. (2010). Effectiveness of a
Participatory Modeling Effort to Identify and Advance Community Water Resource
Goals in St. Albans, Vermont. Environmental Modelling and Software 25.1.
This document considers stakeholder ideas to reduce phosphorous loading and uses models to
determine the impacts on reduction in phosphorus discharge and the costs of the suggested
methods. It will help provide us with a framework to consider stakeholder opinions and solid
data about the potential effects of different management approaches.
Michaud, A. R., I. Beaudin, J. Deslandes, F. Bonn, and C. A. Madramootoo. (2007). SWAT
predicted influence of different landscape and cropping system alterations on
phosphorus mobility within the Pike River watershed of south-western Québec.
Canadian Journal of Soil Science 87. 329-44.
This article will provide some about the sources and magnitudes of phosphorus loading due to
different agricultural land uses. Additionaly, it looks at the effects of agricultural BMPs on total
phosphorus export.
Dillon, P. J., and W. B. Kirchner. (1975). The Effects of Geology and Land Use on the
Export of Phosohorus from Watersheds. Water Research 9.2. 135-48.
This article looks at the effect that geology has on phosphorus loading normalizing for land use.
This information will be used to adjust our risk values for watersheds with a higher or lower
percent of each bedrock type.
Weller, C. M., M. C. Watzin, and D. Wang. (1996). Role of Wetlands Surface Water in
Champlain Basin in Reducing Phosphorus Loading to Eight Watersheds in the
Lake. Environmental Management 20.5. 731-39.
This source discusses the impact of natural wetlands on phosophorus loading for eight
watersheds in the Lake Champlain Basin. It shows that the total area of wetlands and their
proximity to streams had and effect on reducing the total amount of phosphorus discharge by the
watershed. This will inform our evaluation of the risk within each watershed as it shows that
natural wetlands act as phosphorus sinks.
Lake Champlain Basin Nonpoint Source Phosphorus Assessment. (2008). Lake
Champlain Basin Program. http://www.lcbp.org/atlas/html/is_pnps.htm.
This article looks at the relative contribution of various land uses on the loading of phosphorus
into the lake. This was the source of the phosphorus loading information based on land use found
in Opportunities for Action.
State of the Lake. (2008). Lake Champlain Basin Program.
This source is a report on the current state of the lake and provides data that will contribute to
establishing our ranking criteria. It quantifies phosphorus content in loading within our risk
regions for each or our examined sources.
Proposed Effort:
The advantage to examining phosphorus loading into Lake Champlain is that it is a
relatively well-understood and studied process. Full lake monitoring for phosphorus and related
indicators is well established. At our disposal, we have the most recent data on phosphorus
density in different lake segments (State of the Lake, LCBP) as well as determined point and
non-point source loading values subjected to these areas. From our research, we have determined
the main sources of phosphorus as a stressor to be agricultural and livestock areas, wastewater
treatment facilities, and urbanized or developed land cover.
Analyzing how these sources contribute the examined stressor in the different risk
regions is important. Wastewater treatment facilities are most easily quantified. Ranking criteria
will establish assigning a score as a function of number of facilities and total discharge.
Uncertainties exist in how positioning of a facility in an area will impact indicators. Agricultural
and livestock land along with urban and developed land is more difficult to analyze as a source
because they are "non-point" classified. Data does not exist on a small enough scale to
standardize the discharge of each farm or the runoff from each neighborhood. Instead, non-point
loading of phosphorus is an aggregated figure for each risk region. However, we can use the
State of the Lake report to estimate loading percentages for agricultural and developed land use
types combined with total non-point loading totals to get values of input from both categories.
For example, the Lake Champlain Basin Program concludes that non-point loading in the Main
Lake is 139.9 metric tons/year. Developed land accounts for 75% of that load and therefore
104.95 metric tons/year. Ranking criteria can then be assigned based on these calculated values.
The ill-effects of phosphorus include the fact that it acts as a nutrient, thus promoting excessive
plant and algae growth. This situation creates oxygen deficiencies for other species, which
affects the overall functioning of the ecosystem as well as human utilization and enjoyment of
the lake.
Assessment of endpoints must incorporate the two degrees of impacts: ecological and
social. We want the lake to be a healthy system, and we also want people to be able to use and
enjoy it. Assessment endpoints for this stressor should include both an examination of
phosphorus content in the lake as well as blue green algae blooms. Several lake habitats are
affected by phosphorus directly and indirectly. This stressor affects water quality as well as
beaches as locations of recreation. In moving forward, we need to determine specific effects of
phosphorus on habitats and the receptors within the habitats.
Effort Assignment:
Scott plans to investigate the phosphorus contributions of different types of agriculture,
forest cover, and development. Included in this are the beneficial effects of certain cover types,
such as wetlands, as a phosphorus sink. This will allow us to assign risk values that are much
more representative of the relative contributions of each risk region and non-point source. An
additional component of this will be an analysis of the risk that phosphorus loading presents to
the habitat within the streams and ponds that drain into the lake.
Alison plans to research current stormwater and wastewater permits to determine how
much phosphorus is entering the lake from point sources and to identify areas where input into
the lake could be reduced. She also will look into the TMDL to help determine acceptable levels
of phosphorus within the lake as a means of developing indicators for our assessment endpoints.
Alex plans to look at the affects of phosphorus on both the ecology of Lake Champlain
and community use of the Lake and its waters. Analysis of impacts and effects will strive to
cover biological and ecological concerns as well as all stakeholder concerns. We want to know
all ways in which the sources of stressors, and the stressor itself are affecting the quality of the
Lake Champlain and its tributaries.