• Storm System Illicit Discharge Assessment
  SSWM staff inspected and mapped over 1,000 discharge locations to ensure that only rain enters the storm drain system. When water quality tests showed a potential problem, then staff investigated, identified the pollutant source, and removed it from the storm system.
  
  
• Silverdale Stormwater Outfall Detergent Contamination Screening
  Staff tested stormwater outfalls in Silverdale and found that over 40% are contaminated with detergents, mainly from wash water. In 2010, staff repeated the testing to determine the effectiveness of public education efforts in changing the way people wash their vehicles.
  
  
• Silverdale Stormwater Maintenance and Source Control
  SSWM and the Health District partnered with commercial property owners to maintain storm systems on private property. Because of this study, SSWM inspects all commercial properties annually and over 95% of property owners comply with maintenance standards.
  Bacterial Pollution Reduction in an Urban Watershed-Presentation
  Bacterial Pollution Reduction in an Urban Watershed-Technical Paper
  
  
• Removing Pollutants from Roads and Stormwater Structures
  Using vactor trucks, SSWM routinely removes sediment from catch basins, vaults and ponds. In addition, the high-efficiency street sweepers remove pollutants from roads. Staff determines the amounts of pollutants removed to help measure the benefits of these maintenance activities. For more information, click here to read our "Preventing Pollution from Entering our Waterway" factsheet.

Evaluating Stormwater Treatment Technologies

• Southworth Drive Stormwater Treatment System Monitoring
  SSWM will monitor the sediments that a Vortechs® stormwater treatment system removes from the street runoff.
  
  
• Pervious Pavement Infiltration Testing
  Staff uses an infiltration test to evaluate how well water can soak through these new pavement surfaces, including how well maintenance prevents clogging.
  
  
• YMCA Low Impact Development Performance Study
  Staff will evaluate the overall benefits of the LID facilities and also compare pervious concrete to normal asphalt.
  Project Approach Memo
  Pervious Pavement Installation Photos

Monitoring Construction Projects that Improve Water Quality

• Downtown Silverdale Ridgetop Boulevard Swale Retrofit.
  Staff collected samples before and after the retrofit to gauge the effectiveness of the swale’s redesign. 
  
  
• Kitsap County Fairground Retrofit
  Fecal coli form levels will be monitored at the mouth of Barker Creek and the adjacent marine station in Dyes Inlet before and after the LID installation to evaluate their effectiveness in improving water quality.

Kitsap County Public Works                                                                                      Updated: 06/24/2011
Surface & Stormwater Management Program
(360) 337-5777 or (800) 825-4940
Kitsap1@co.kitsap.wa.us