9th Street Basin Stormwater Retrofit | 2025 Top Projects
The 9th Street Stormwater Retrofit project in Wenatchee, Washington, was implemented to improve stormwater drainage and enhance water quality in the 620-acre 9th Street basin, which discharges into the Columbia River and No. 2 Canyon Drain. Prior to the retrofit, stormwater in the area did not recieve treatment which created risks for wildlife and recreational water use.
The retrofit faced significant design challenges, including low-lying terrain, limited space and aging infrastructure in a densely populated area. Engineers created a cost-effective, low-maintenace solution that fit within the existing built environment without requiring land acquisition. The city had to coordinate with the Army Corps of Engineers due to the unique canyone drainage system that runs through the city.
The success of the project stemmed from collaboration between the city and Osborn Consulting Inc., contractor J&K Earthworks, Wenatchee Valley College, Cascade Natural Gas and state and federal funding partners, including Washington Department of Ecology and the U.S. Environmental Protection Agency's (EPAs) Clean Water State Revolving Fund (CWSRF). The project leaned on community outreach and communication with stakeholders to help mitigate construction impacts.
The project was completed ahead of schedule and under budget, with a total cost of just over $1.4 million, nearly $600,000 under budget.
The retrofit improved stormwater treatment, reduced pollutant discharge to the Columbia River and offered flood mitigation and protection of critical salmon habitat. The project, which was designed to capture and treat runoff, serves as a model for cost-effective urban stormwater improvements that balance environmental protection, infrastructure longevity and community collaboration.
