CSO Reduction Pump Station
city of snohomish
The first phase of the City of Snohomish’s Combined Sewer Overflow (CSO) project involved the reduction of untreated sewage flow from the historic downtown area going into the Snohomish River during heavy rains. The project also transitioned the site from its current use as a maintenance yard into a city park surrounded by trails.
To meet the client’s goals—to produce a building that would complement the City’s industrial past and historical present—RAI’s team incorporated unique building elements including special masonry, exposed structural steel, and customized lighting fixtures. The multi-colored brick exterior and the “flying” roof line supported by ornamental brackets match the City’s historic buildings. Colors and finishes were chosen to complement the artistic theme. Rain gardens were installed to capture and treat runoff from surrounding paved areas. Accordingly, trails around the pump station and future public restrooms in the pump station building were incorporated into the design.
The project posed some difficult challenges, including an issue with the regional flooding from the Snohomish River. Our solution was to site the building so that it would be located above the high water level. This strategic placement ensured that maintenance would be able to access the building at all times, even during flooding or heavy rainfall. This was an important aspect of the design since the pump station contains electrical panels that need to stay dry and accessible to maintenance staff at all times.
Another issue was the potential noise pollution due to the pumps. Since the pump station is located near a residential neighborhood, we wanted to make sure it didn’t negatively impact the quality of life of local residents. Our consulting with an acoustical engineer resulted in the successful design of this building where the noise created by the pumps was concealed.