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Why bother?
Rain collects pollution.

While raw sewage in our waterways poses health risks for people, polluted stormwater runoff also has a big impact on water quality. Rain lands on streets, yards, and other places, where it collects pollution such as:

  • pet waste
  • oil and heavy metals from vehicles
  • fertilizers and pesticides from yards

Those pollutants run off with the rain into the local waterway.

The Integrated Plan Alternative

The Integrated Plan includes projects to protect all of Seattle’s waterways from polluted stormwater runoff.

We’re evaluating two alternatives in the Plan to Protect Seattle’s Waterways:

  • Integrated Plan (pdf) uses an integrated approach to reduce both sewage overflows and polluted stormwater runoff; some projects built after 2025.
  • Long-term Control Plan addresses sewage overflows only; all projects built by 2025.

If adopted and approved, the Integrated Plan would implement stormwater quality projects before some smaller-volume sewage overflow projects. SPU would also build sewage overflow projects in 11 neighborhoods. Those projects that address the largest, most frequent overflows still would be built by 2025; smaller-volume projects would be built after that.

See a map of the Integrated Plan Stormwater Projects (pdf).

The Integrated Plan includes three sets of projects to prevent polluted runoff:

  • Arterial Street Sweeping Expansion
  • South Park Water Quality Facility
  • Natural Drainage Systems Partnering

Read more in the Community Guide to the Integrated Plan (pdf).