(Photo credit: Eric Boerner, Alaskan Fisheries Science Center, NOAA)

Runoff from the Built Environment

Stormwater runoff has been found to be the number one contributor of contaminants entering into Puget Sound (WDOE, Pub. # 07-10-058).

Stormwater runoff forms when precipitation from rain, snowmelt, and groundwater discharge accumulates over land and built surfaces (streets, parking lots, and rooftops). This runoff deposits sediments, debris, and pollutants (e.g. fecal coliform, total petroleum hydrocarbons, heavy metals, etc.) into local watersheds. In the San Juan Islands, everything drains into our nearshore marine waters. If left untreated, contaminants can persist and adversely affect the health of marine mammals, fish, and birds, as well as people, in the San Juan Islands.

Marine mammals and fish living within the wider Puget Sound are known to have high levels of toxins, whether through direct exposure or bioaccumulation through the food chain (West et. al. 2008; Oneil et al. 2008). In fact, endangered Southern Resident Killer Whales and transient killer whales (Orcinus orca) in Puget Sound are found to be one of the most contaminated cetaceans in the world (Ross et al. 2000). Studies of harbor seals (Phoca vitulina) also indicate high levels of PCBs in samples of their blubber tissues (Ross et al. 2004) and in their food sources (Cullen et al. 2005; West et al. 2008). Interestingly, these cumulative studies also indicate that the level of toxicity may be directly linked to localized waters. Harbor seals and their food sources were found to have toxicity levels seven times higher in Puget Sound than Georgia Strait. Stormwater management, therefore, is often best addressed at a local level and then coordinated with regional ecosystem management.

Strategies & Local Near-term Actions

The SJ-LIO identified specific local strategies and actions to reduce run off from the built environment. The latest 2014/2015 Action Agenda near-term actions (NTA)’s, along with the local entities working on these, are listed below:

  • Control and mitigate stormwater runoff by improving the stormwater review process and permitting for San Juan County and the Town of Friday Harbor, and construct a waterfront stormwater vault containing Ecology-approved cartridge filters (San Juan County Health and Community Services Department, Town of Friday Harbor).
  • Fully implement the Onsite Sewage System Operation and Maintenance Program Plan (San Juan County Health and Community Services Department).
  • Provide technical and financial assistance, outreach, incentives, education and natural resource planning on a voluntary basis to interested residents to improve stormwater management and reduce polluted runoff and nutrient loading into the marine environment (San Juan Islands Conservation District, Friends of the San Juans, San Juan County Department of Community Development, San Juan County Public Works Stormwater Utility, Town of Friday Harbor, San Juan County Health and Community Services Department, San Juan County WSU Extension).
  • Devise monitoring and management plans for priority and/or focus basins (San Juan County Public Works Stormwater Utility, San Juan County Stormwater Committee, San Juan County Water Resources Committee, San Juan Marine Resources Committee, Town of Friday Harbor, San Juan Islands Conservation District).



Implementation Committee Meeting:

Bimonthly first Thursdays, 11:00 am -1:00 pm, 7/1, 9/2, 11/4
See San Juan County website Agenda Center for agendas and meeting links

Accountability Oversight Committee Meetings:

Schedule pending

Padilla Bay National Estuarine Reserve, 10441 Bayview Edison Road, Mount Vernon



San Juan County Oil Spill Risk Consequences Assessment and Emergency Response Towing Vessel Cost Evaluation, March 2019