Stormwater Maintenance

The Stormwater Division is responsible for the maintenance and repair of:

• 320 miles of pipe
• 12,125 catch basins
• 285 vaults
• 141 bioswales
• 84 ponds.

The stormwater system is designed to prevent flooding and reduce the water quality impact runoff has on Lake Sammamish, the Sammamish River, and multiple creeks. Many features of the stormwater system collect sediment, pollution and debris, and require regular maintenance to remove collected materials before they enter the natural environment. 

Maintenance activities include:

• Inspect, clean, and repair catch basins every two years. 
• Inspect, clean, and repair stormwater vaults and ponds annually.
• Inspect, clean, and repair low impact development stormwater facilities such as bioswales and rain gardens annually. 
• Operate and maintain the City’s decant facility which process liquid and solids collected from streets and sewers.