CITY OF RENTON WASHINGTON

Design Services
The Surface Water Utility solicited qualifications from consultants in accordance with City policy 250-02. Six responses were received and evaluated.  Louis Berger U.S., Inc. ranked the highest and was selected to perform this work.

Council awarded the contract to Louis Berger U.S., Inc. in the amount of $111,600, for engineering design services, at its regular meeting on January 7, 2019.

The design phase (February 2019 – December 2020) is partially funded by a grant from the Washington State Department of Ecology 2017 Water Quality Combined Financial Assistance program.  The construction phase (summer 2021) is partially funded by a grant from the King County Waterworks program.

Construction Services
Twelve contractors submitted bids for the project on April 15, 2021. The lowest responsive and responsible bidder is Diversified Holdings NW in the total amount of $208,983.36.  Schedule A represents the work associated with the retrofit of the pond while Schedule B includes storm system upgrades along Union Avenue SE in the vicinity of the project area. The bid schedule A is $148,889.08. The bid Schedule B is $60,094.28. 

Seventy-five (75) percent of the construction cost of Schedule A will be funded by Ecology’s FY 2020 Stormwater grant. The remainder will be covered by a King County Waterworks grant. Funding for Schedule B is available from the approved 2021 Surface Water Utility Capital Improvement Program budget for the Heather Downs Detention Water Quality Retrofit Project. 

Stormwater runoff from approximately 30 acres of predominately impervious area including driveways, streets, buildings, and other impervious areas collects in catch basins and pipes and flows to the Heather Downs Detention Pond, where it currently provides no treatment runoff. The pond runoff discharges to Maplewood Creek, a tributary to the Cedar River, and ultimately to Lake Washington.   

The project will retrofit a city-owned detention facility in the Heather Downs residential development to be a combined detention and water quality treatment facility. This stormwater facility will provide flow control and additional basic water quality treatment to remove pollutants from streets and other pollution generating surfaces within a 30-acre drainage basin.

Figure 1 - Heather Downs Vicinity Map
Figure 2 - Heather Downs Detention Pond Map
Figure 3 - Heather Downs Outfall Pipe Map