Seattle Public Utilities

South Park Conveyance


Current South Park Conveyance study area; boundaries may change based on technical feasibility.

What & Why

Seattle Public Utilities is currently working on three stormwater projects in northwest South Park's lower industrial basin to reduce flooding and improve water quality in the Lower Duwamish Waterway.

The South Park Conveyance project will complete design for a new stormwater collection system in roadways that don't currently have one. Scope and budget will ultimately determine which roads will receive new drainage systems. Selected roadways will be rebuilt to ensure they drain into the new inlets and catch basins.

We are also planning two additional projects in the lower industrial basin:

  1. A flood control pump station to overcome the flooding effects of high tide.
  2. A water quality facility to treat stormwater from the storm drain system before it flows into the Duwamish Waterway.

The South Park Conveyance project is supported in part with funding from the King County Flood Control District.

What’s happening now?

The South Park Conveyance project is a joint effort with SDOT. The project is currently in the design phase for improvements to the drainage system and streets. The joint project team is working with technical consultants to determine the best approach and sequencing for the planned improvements.

In 2017, we gathered feedback from lower industrial basin businesses and residents on how they utilize the right-of-way, drainage and flooding issues they experience, and SPU’s proposed plan. We will use this feedback to inform drainage system design.

SPU is analyzing and planning drainage improvements for the entire project area, but the 2018-2023 budget is not sufficient to complete all the work. The plan will include all the work, along with a phased approach for full implementation. The initial phase of construction will be based on available budget.

Project goals and benefits

When complete, this project will work in tandem with the flood control pump station to reduce flooding in the industrial and residential areas in the northern part of South Park. The pipe improvements will collect and convey flows to the existing drainage system and lessen overall flooding. The drainage system will direct stormwater to the flood control pump station, which will pump stormwater to the Lower Duwamish Waterway, and to the future water quality facility

Meetings & Events

No meetings scheduled at this time.


Jason Sharpley, project manager
(206) 615-0030

Sheila Harrison, line of business representative
(206) 684-5899

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