Dosewallips Sewer System Replacement

Looking at the Dosewallips River toward the Olympics

Contact Us

  1. Brian Yearout
    Project Manager

    P.O. Box 42650
    Olympia, WA 98504-2650

    Ph: (360) 725-9763
    Fx: (360) 902-0207

The new sewage system at Dosewallips State Park will replace the aging septic system at the park with an improved treatment process that decreases negative impacts to groundwater quality. In 2010, the project was split into five construction phases:

• Phase 1 – Collection: This project was completed in 2011 and constructed the force main within the campground.

• Phase 2 – Conveyance: This project was completed in 2011 and constructed the force main from the park to the treatment site (Green Hill Property).

• Phase 3 – Sitework: This project was completed in 2011 and cleared the Green Hill treatment site and constructed a gravel entrance road and gate.

• Phase 4 – Treatment: This project will construct the MBR and infiltration basins at the Green Hill Site. Scheduled to be completed in early 2015

• Phase 5 – Collection II: This project will construct the grinder pumps within the campground. Scheduled to be completed in early 2015.

The new system will help support State Parks’ mission of natural resources stewardship and is also part of a comprehensive regional cleanup effort known as the Puget Sound Initiative.

Puget Sound and Hood Canal are ecosystems in trouble. When toxic pollutants from various sources get into the water, they settle to the bottom, working their way into the food chain and accumulating, ultimately threatening the entire ecosystem. To address the problem, Gov. Christine Gregoire and the Legislature launched the Puget Sound Initiative in 2005, to restore, protect and preserve Puget Sound by 2020. The comprehensive effort includes local, state, federal and tribal governments, as well as scientists, business, agriculture and the public.


An informational meeting was held in Brinnon, WA on May 8, 2014. The PowerPoint presentation that was reviewed during the meeting is below.