CITY OF RENTON WASHINGTON

The Madsen Creek Flood Risk Reduction Project preliminary investigation and alternatives analysis is funded by the King County Flood Control District Flood Reduction Grant, in the amount of $472,000. The final design and construction is funded through a CIP Grant awarded by the King County Flood Control District in the amount of $615,000.

Design
The Surface Water Utility solicited proposals from consultants in accordance with City policy 250-02. All proposals were evaluated and three consultant firms were selected for interviews. Watershed Science and Engineering, Inc. ranked the highest and was selected to perform this work.

Council awarded the contract to Watershed Science and Engineering, Inc., in the amount of $466,098, at its regular meeting on May 14, 2018. The contract was amended December 21, 2020 to include the completion of final design and construction support services in the total amount of $639,776.

Construction
The Surface Water Utility solicited bids from contractors in accordance with City policy 252-02. Three bids were submitted on July 25, 2022, and Sierra Pacific Construction, LLC has been selected as the contractor for the project.

On August 22, 2022, Mayor Armondo Pavone executed the construction contract, in the amount of $338,674.21, with Sierra Pacific Construction, LLC.

The design phase of the project includes surveying, hydrologic analysis, hydraulic analysis, and environmental analysis to better understand and assess the causes of the flooding problems. This includes the identification of short-term and long-term solutions to alleviate the risk of flooding in the affected areas, and the preliminary design of the preferred solution. Once the preferred solutions are determined, the first phase will be completed and will include final design and permitting.

The construction phase of the project will include construction of drainage improvements and construction support services.

The project is wrapping up construction. All channel excavation, berms, concrete masonry units walls, erosion control protection, hydroseed, and plantings are to be completed by the first week of October. 
Once construction is complete, the City of Renton will perform a punch list with the contractor to ensure that all construction items are completed to a satisfactory level.

We are excited to have this project complete before the winter of 2022/2023 to reduce the flood risk to the surrounding residents.

Figure 1 - Madsen Drainage Basin - All
Figure 2 - Madsen Project Area