Shape Our Water Reports

The reports on this page are being used to inform Seattle Public Utilities’ (SPU) future drainage and wastewater system investments. Learn about Shape Our Water – a community-centered plan for Seattle’s next 50-years of resilient drainage and wastewater systems and how we can work together at our Shape Our Water website and in our Shape Our Water fact sheet.

Too Much, Too Fast (Water Quantity)

Seattle has more than 1,400 miles of wastewater pipes and more than 400 miles of drainage pipes – many of which were built 50-100 years ago. SPU invests in projects every year that increase the capacity of the drainage and wastewater systems but, in some places, flows still overwhelm the pipes. These reports identify and prioritize areas that may be vulnerable to flooding and sewer back-ups because of capacity issues.

Pollution in Our Waters (Water Quality)

Seattle invests in many programs and projects that help reduce how much pollution enters our lakes, creeks, Puget Sound and the Duwamish River. These reports provide information about our priorities for continuing to protect water quality and reducing combined sewer overflows (CSOs).

  • Combined Sewer Overflows: The City’s Plan to Protect Seattle’s Waterways identifies areas of Seattle where reducing combined sewer overflows is needed to meet state and federal regulatory requirements and Annual Reports document the City’s progress implementing the plan
  • The City’s Stormwater Management Plan identifies our work to protect stormwater quality and reduce pollution in our waters. The Stormwater Management Plan satisfies the requirements of the Clean Water Act and meets state requirements
  • Water Quality Summary (1/6/20): Summarizes known water quality data and evaluates receiving water bodies (lakes, creeks, etc) and stormwater basins to determine priorities for structural stormwater control projects

Creek and Shoreline Health

These reports provide information about the various challenges and opportunities associated with the health of Seattle’s creeks and shorelines.

  • Creek Flow Metrics (12/21/20): Estimates how much stormwater runoff contributes to creek flows
  • Fish Passage Barriers (6/26/19): Summarizes previously identified and prioritized fish passage barriers on Seattle’s creeks
  • Aquatic Habitat (10/28/20): Documents known aquatic creek habitat condition and fish usage in creeks and summarizes previously identified priority areas and sites for salmon recovery, shoreline restoration and creek daylighting
  • Floodplain Reconnection (10/28/20): Summarizes previously identified and prioritized floodplain reconnection opportunities on Seattle’s five main salmon-bearing creeks

Shocks and Stresses

These reports provide information about the challenges in Seattle associated with climate change and extreme events.

  • Extreme Storm Analysis (10/9/20): Identifies areas that may become inundated due to extreme storm events and characterizes them based on risk
  • Flooding - Creeks Analysis (10/9/20): Identifies areas that are susceptible to flooding along creeks and characterizes them based on risk
  • Geologic Hazards (10/26/20): Identifies known landslide areas and liquefaction prone areas in Seattle
  • Sea Level Rise Analysis (10/5/20): Identifies areas that may become inundated due to sea level rise and characterizes them based on risk
  • Seismic Risk Assessment (2/17/2022): Identifies and prioritizes seismic risks in SPU’s drainage mainlines, wastewater mainlines and wastewater facilities
  • Non-Potable Water Demand (9/3/20): Identifies areas of the city that show the greatest potential demand for non-potable water
  • Social and Environmental Systems (2020): Highlights Seattle’s current racial inequities in health, wealth, and environmental quality
     

Disclaimers

The information, data, analyses, and content provided on this website are prepared for use by The City of Seattle for its internal purposes only, by and for Seattle Public Utilities Drainage and Wastewater Line of Business solely for its long-term planning efforts, and is not designed or intended for use by members of the public for private, commercial, or any other use. ALL SUCH INFORMATION, DATA, ANALYSES, AND CONTENT IS PROVIDED ON AN "AS IS", "AS AVAILABLE" BASIS WITHOUT WARRANTES OF ANY KIND EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, AND NON-INFRINGEMENT. The City of Seattle makes no representations or warranty as to its accuracy for any use. In no event will The City of Seattle be liable for any loss or damage including without limitation, indirect or consequential loss or damage, or any loss or damage whatsoever arising from loss of data or profits arising out of, or in connection with, the use of any information from this website. All persons accessing or otherwise using this information, data, analyses, and content assume all responsibility for its use and agree to hold The City of Seattle harmless from and against any damages, loss, claim or liability arising out of any error, defect or omission contained within said information, data, analyses, or content.