Progressive Design-Build Surface Water Interceptor Project Adds Capacity to Support Growth in Downtown Tacoma, Washington

The City of Tacoma’s Jefferson Avenue and Hood Street Surface Water Interceptor Project will play a vital role in providing additional surface water capacity to alleviate flooding and increase capacity for growth in the downtown area. Project improvements included approximately 3,200 ft of new 48- and 60-in. surface water conveyance pipe; trenchless crossings of mainline railroad tracks; sound transit light rail tracks and a major city arterial; tie-ins to existing active pipelines; and a new marine outfall with adjoining shoreline improvements. The city elected to use the progressive design-build procurement method because of the alternative alignments available, the extensive permitting processes required, the railroad and light rail crossings, and the many stakeholders and downtown businesses impacted by the project. The paper will review the process for selection of alignment and project delivery method, which relied on a conceptual design to bring in a contractor partner to collaborate with the city in navigating challenging right-of-way crossings in difficult soil conditions.