Delridge Basin
Project Update
Thanks to everyone who came to our October 4, 2012 meeting to discuss how to prevent sewage overflows into Longfellow Creek. View the October 4, 2012 presentation (pdf).
Read the questions and comments from the meeting (pdf). Sign up for project e-mail updates.
View the display boards from the meeting (pdf).
Soil borings were taken around Highland Park to gather data about soil and groundwater conditions. See the map of locations (pdf).
We will share the results of these tests in 2013.
Sewer and Stormwater Pollution
In the Delridge area, sewage and stormwater overflow into Longfellow Creek, even when it rains less than two inches. In 2011, more than 1.33 million gallons of sewage and stormwater overflowed into the creek.
Stormwater found toxic to salmon (KOMO News)
Delridge Basin Projects
As part of a citywide program to prevent sewer overflows, SPU is investigating the scope of the Delridge problem and possible solutions. Current plans call for projects to be built in 2014:
- Fix It First—retrofit existing storage tanks to control up to 100 percent of the total volume.
- Keep the Stormwater Out—add Green Stormwater Infrastructure (GSI), such as raingardens and cisterns, to protect Longfellow Creek from polluted runoff.
- Store What’s Left—if the retrofit and GSI projects are as successful as expected, a new storage tank would not be needed.
Contact Us
Contact April Mills at april.mills@seattle.gov or (206) 733-9816 if you have questions or concerns.