Tukwila South Development

LaPianta LLC required preparation of a comprehensive stormwater management approach and plan for the proposed Tukwila South development in Tukwila. The plan included the design of stormwater infrastructure, sizing water quality treatment facilities, design of detention facilities, hydraulic analyses of stormwater conveyance systems, and evaluation of the effects of interactions with the Green River.

Role / Services: Larry was the managing hydrologist and hydraulic engineer responsible for the evaluation of on-site stormwater control and the mitigation of potential downstream impacts of the proposed project. Hydrologic and hydraulic modeling was conducted using HSPF, SWMM, HEC-RAS and River2D. These tools were applied in support of fish habitat restoration project design, levee setback project evaluation, and environmental permitting. Larry's work on this project began while he was at NHC and has continued at WSE.

Outcome: The Tukwila South project represents an ambitious effort to develop a business campus in the Green River valley and attract high tech companies from around the world. The project faced significant challenges with regard to stormwater management and interactions with the Green River. Larry's leadership and technical expertise has been critical in helping to design a project that successfully meets the requirements of numerous reviewing agencies.