As part of the Spot Drainage Program, Seattle Public Utilities has a team from R.W. Beck working on 36 drainage problems, 23 of which already have been designed. Approved designs are channeled to one of two firms SPU has contracted to complete the work. The anticipated construction deadline for many of these drainage solutions is the end of the year, in time to help protect city residents and properties from the upcoming winter wet season.
A typical site is in the Crown Hill neighborhood of northwest Seattle. Landslides have occurred near homes along the street because street runoff flows off the roadway down a potentially unstable slope. The team is working on reducing persistent flooding problems that must be addressed on an area-wide basis.
Initially, SPU identified three basin-wide solutions for analysis: storm drain upgrades to increase capacity, storm drain upgrades with large-scale detention to reduce peak flows, and supplemental detention requirements for new development.
