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Under WAC 400-12-515(3), the Watershed Management Committee is required to develop a Problem Definition that includes the beneficial uses of water that are threatened by non-point source pollution. This involves evaluating how well the water quality standards for surface waters are being met, what the existing and potential impacts are, how wetlands are affected, and to list and rank the existing and potential sources of nonpoint pollution. Finally, using the information gained through the problem definition process, a water quality program is developed to correct known pollution sources and to prevent future ones. This water quality program will be presented in the following sections on Implementation Strategies.
In order to evaluate beneficial uses and sources of nonpoint pollution, the San Juan County Watershed Management Committee used a ranking process that assigned a numeric value to each beneficial use and each pollutant source.
Beneficial uses of water
The Committee identified six categories of beneficial uses of water:
- domestic supply,
- habitat/special areas,
- recreation,
- agriculture,
- commercial-industrial, and
- aquaculture.
Domestic supply and habitat/special areas were ranked equally as the highest category of use, with recreation in the next category, and agriculture, commercial-industrial and aquaculture ranked equally in the bottom category.
Domestic water supply is a critical resource in San Juan County. Habitat for wildlife -- such as, wetlands, stream corridors, forest, grass lands, and nearshore areas -- is ranked as equally important and the Committee included in this category the term special areas, to acknowledge the value of the many research/educational/biologic preserve areas in the county. When the Committee ranked the pollution threats to beneficial uses, habitat/ special areas received the highest rating with 33% of the points given. Domestic supply was a close second with 28% of the points.
The beneficial use of the county's waters
for recreation is important for the economy and for education
and public enjoyment. Recreational use, which includes shellfish
harvesting, swimming and other human contact with water, was
ranked as the third most threatened by non-point pollution sources
with 15% of the total ranking points. Finally, the essential
commercial benefits of water use for agriculture, commercial/
industrial activities, and aquaculture are identified. The Committee
recognized that aquaculture is an important industry and especially
vulnerable to non-point pollution, although not as extensive
as other beneficial uses.
Sources of pollution
The Committee then identified the sources of nonpoint pollution in San Juan County. These are:
- on-site septic systems;
- conversion of forest-, grass- and wetland areas to residential and commercial developments;
- stormwater runoff;
- agricultural practices;
- forestry practices;
- marinas and boating activities; and
- solid waste/hazardous waste.
For each source of pollution a ranking process was done for each of the nine priority watersheds. This process involved rating the various sources of pollution based on existing and potential impacts. In some cases, a shortage of firm data forced the Committee to rely on anecdotal information, and through a process of subjective consensus the Committee assigned values in the ranking steps. After the numbers were added up, the Committee discussed the relative rankings at length, and decided that the final outcome should reflect their conclusions about the overall threat from each source of pollution. The sources were grouped into three levels: first, second and third; or high, medium and low. See Table A at the end of this section to review the rankings.
Although the numbers varied between individual watersheds the relative rankings for the pollution sources were consistent. On-site septic systems and conversion of resource lands had the highest overall numeric score, with stormwater runoff also included in the first level. County-wide, on-site septic systems, conversions, and stormwater runoff are ranked as the primary pollution sources. Agriculture is ranked as a second level pollution source. And, marinas, forestry practices, and solid/hazardous waste are ranked, overall, as a third level concern.
Looking at individual watershed rankings, the threat of failing on-site septic systems ranked highest for the Westcott/Garrison, East Sound, Fisherman Bay, and Mud/Hunter watersheds. Contamination from failing septic systems has been documented or reported in these areas. Conversion of resource lands ranked as the highest source of pollution for Deer Harbor, a small watershed with steep terrain that is undergoing clearing of forest lands for residential development. Marinas ranked highest for Roche Harbor, the smallest priority watershed, with an extensive resort and marina complex. Stormwater runoff ranks highest for the Friday Harbor watershed, which includes the largest urban area in the county. Agricultural practices rank highest in the False Bay and Westsound watersheds, where the most extensive agricultural lands and livestock operations in the county are found.
1. An evaluation of current conditions resulted in an initial ranking for agricultural practices as low, but the Committee concurred that changes in agricultural activities from traditional agriculture to rural-residential land use indicates a high potential for pollution. This trend involves a greater density of livestock and more intensive use on smaller acreage.
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