Preventing Sewer Overflows and Problems
No one wants their sewage back! SPU works to maintain, build and manage Seattle's sewer system to protect our city and the environment from overflows and backups.
To do this, SPU:
- Maintains the sewer system
- Builds sewer system projects
- Manages stormwater that enters the sewer system
- Helps customers with side sewer maintenance and proper flushing
About Combined Sewer Overflows (CSOs)
CSOs are one type of sewer overflow. Use our map to find current or recent overflows.
Since 2008, we have invested almost $1 billion to reduce CSOs. We are reducing pollution in our waters. Learn more about our commitment to CSO reduction:
- Achievements in Reducing Combined Sewer Overflows
- Hear more about Our Commitment to Reducing Combined Sewer Overflows
- Find our largest CSO project, the Ship Canal Water Quality Project
- Learn more about SPU’s Plan to Protect Seattle’s Waterways (2015)