The recent study conducted by the Washington State Department of Ecology has identified multiple sources contributing to the elevated bacteria levels in Drayton Harbor. Runoff from agricultural lands was pinpointed as a primary culprit, with nutrient-rich waters carrying fertilizers, animal waste, and soil into the harbor. Additionally, failing septic systems in nearby residential areas exacerbate contamination, allowing harmful bacteria to seep into groundwater and flow toward the bay. Urban stormwater also plays a significant role, transporting pet waste, litter, and automotive residues from city streets directly into the marine environment during rainfall events.

Environmental challenges complicating remediation efforts include:

  • Seasonal variations causing fluctuating bacterial concentrations
  • Complex hydrodynamics of Drayton Harbor limiting natural dilution
  • Inadequate infrastructure to manage stormwater and sewage overflow
Source Impact Level Remediation Priority
Agricultural Runoff High Urgent
Septic Systems Moderate High
Urban Stormwater Moderate Medium