One big topic at this past week’s monthly HPAC meeting – the plan for another giant storage tank in West Seattle to contain combined-sewer overflows.

HPAC is the community coalition for Highland Park, Riverview, and South Delridge; co-chair Kay Kirkpatrick facilitated the online meeting on Wednesday night.

WEST DUWAMISH CSO CONTROL PROJECT: We mentioned this project three weeks ago, while commenting time was open for its environmental checklist. The King County Wastewater Treatment Division sent reps to the HPAC meeting to present a briefing on the plan. Project manager Maud De Bel led the presentation, calling the West Duwamish Combined Sewer Overflow Control Project‘s central feature “similar to the Murray (Wet Weather) Facility” across from Lowman Beach Park. She offered a quick refresher course on combined sewers – stormwater running off streets and roofs, going into the sewer system – “there’s a point where the sewer gets overwhelmed,” so to prevent floods and backups, the system overflows into bodies of water like Puget Sound or the Duwamish River. The county has controlled “most of those” but this project is meant to address two areas of eastern West Seattle where uncontrolled overflows go into the river several times each year.

Above ground, the new storage tank – 1.25 million gallons, just a bit larger than the five-year-old Murray tank – will cover ground “the size of two Olympic swimming pools,” said de Bel. But it won’t be anywhere near as large as the Georgetown treatment facility that’s being built on the other side of the 1st Avenue South Bridge, which is due to come online later this year. The West Duwamish project is at 30 percent design right now. Currently the tank site is owned by the port and is used for truck parking; that contract will end when the project is ready to begin.

(WSB photo)

The site is close to the encampment in the area but de Bel said the project won’t be displacing it.

Other project points: If the tank is full, in an extremely heavy rain event, there’s a chance the system will still overflow into the Duwamish – the consent-decree requirement is to limit that to an average of one overflow per year. The outfall is at the end of SW Michigan “right under the (1st Avenue South) Bridge,” de Bel said. But that’s not part of the project site, which does not include shoreline.

In Q&A – Project cost? $110 million. With the historic tribal sites in the area, are they working with the Duwamish Tribe re: impacts, art, etc.? 4Culture is responsible for that part of the project, said de Bel, while colleague Amelia Bahr said that they’ll be “reaching out” at a later stage of the process. King County already is speaking with the “treaty tribes” in the area (Muckleshoot and Suquamish), added Cari Simson, a consultant working on the project. She added that they’re looking for more opportunities for community-benefit projects in surrounding West Seattle and South Park neighborhoods, since the immediate vicinity of the project is relatively isolated.

More questions: Will the biking/walking Duwamish River Trail stay open during construction? The project team believes it will. Will there be traffic impacts with this project? Nothing major – the new facility will connect to pre-existing underground pipes that already bypass the busy streets. Since most of this site will be landscaping over the tank, with a small above-ground building, will the landscaped area be accessible to the public? That’s still under discussion. When will design concepts be made public? This summer. HDR is the design consultant; MIG is the landscape designer. What kind of cleanup will be needed during the excavation? They’re still analyzing the soil. But so far, it “doesn’t seem that contaminated” – it’s primarily river sediment that hasn’t had much of anything built over it. What else will be done with the site? The site may include a “little hub” for King County staff.

You can sign up for email updates via the project website.

Also at the HPAC meeting:

POLICE: Lt. Dave Terry was there from the Southwest Precinct to field any community concerns; Kirkpatrick said the only concern she’d received from a resident was about encampments in/near Westcrest Park. Lt. Terry said that while police aren’t dealing with encampments, the city asks that people report problems via Find It Fix It so the city can prioritize trouble spots. Kirkpatrick also mentioned the recent citywide crime-trend report that noted Westwood Village is high on the list of city hotspots for 911 calls. Terry said the Target store – since the chain is targeted around the region – is a magnet for frequent theft. Police are still spending time on “emphasis patrol” at Westwood every day they can.

QUICK NOTES: Neighbors are urging Seattle Parks to work on the Riverview trail that’s been deteriorating – apparently the concrete strike is also affecting availability of gravel … HPAC is mulling a return to in-person meetings, though the question is “where?” given the fire closure of Highland Park Improvement Club … Temporary pop-up art installations are in the works for the Highland Park Neighborhood Greenway … Everyone’s invited to help with a Duwamish River cleanup on March 13th … Next HPAC meeting: March 23rd, 7 pm. Watch hpacws.org for updates.