VIDEO: You’ve probably passed it many times. Now, see inside King County’s water-cleaning facility just off 1st Ave. S. Bridge

(WSB photos and video)

With another “atmospheric river” on the way, the King County Wastewater Treatment Division‘s Georgetown Wet Weather Treatment Station is gearing up for another potentially busy run of intercepting contaminated runoff/overflow water before it gets to the Duwamish River. This is the year-old facility you may have driven or rode past many times, near the north end of the 1st Avenue South Bridge, on the northwest corner of 4th and Michigan. Today the county gave media crews a behind-the-scenes tour.

Operating the quarter-billion-dollar facility – built over more than four years – is not labor-intensive – just one person is needed at all times to run it, and if there’s a major storm event sending millions of gallons of water through it, that rises to a grand total of three. It can handle up to 70 million gallons of combined-sewer overflow per day. (So far its peak usage has been 26 million gallons a day during an early December storm.)

Unlike the county’s Murray Wet Weather Facility by Lowman Beach, and the West Duwamish Wet Weather Storage Facility that’ll be built on our side of the 1st Avenue South Bridge, the Georgetown facility is a treatment plant – taking solids out of the water via a “high-speed settling tank” using materials like the sand in these bags to quickly pull the solids out of the water:

The solids eventually wind up in agricultural use. The filtered water gets disinfected with ultraviolet light:

After all that, the treated water gets sent into the Duwamish River, via an outfall under the nearby bridge.

King County Executive Dow Constantine gave the overview of the plant, noting it’s won awards and is intended for climate resiliency, including the fact it was built to handle up to two feet of sea-level rise:

(added) Rebecca Singer, who oversees facilities including this one, said this rainy season is the real test for the treatment station:

The facility also has interpretive features and gets visits from students.

The county has been working on combined-sewer-overflow reduction for more than a decade under orders from the federal government to reduce the overflows into local waterways. The consent decree related to this gave a deadline of 2030 to meet the goals; we asked Wastewater Treatment Division spokesperson Alison Hawkes how much progress the county has made: “We built the Georgetown Wet Weather Treatment Station as one of our commitments in the consent decree. We have controlled a number of outfalls already, and are working to meet requirements on others. Some of the details on this future work, such as the timeline, are in negotiations with EPA and [state] Ecology as part of our request for modification of the consent decree – that information will be released to the public once negotiations are finalized.”

15 Replies to "VIDEO: You've probably passed it many times. Now, see inside King County's water-cleaning facility just off 1st Ave. S. Bridge"

  • WS Resident January 24, 2024 (6:43 pm)

    Makes me wonder about that water 20 years ago when I regularly dove at Alki 😞

  • Kt January 24, 2024 (7:41 pm)

    Thanks for posting this.  Was curious about what went on there.

  • Lorraine January 24, 2024 (7:53 pm)

    This is so cool! 

    • Beth January 24, 2024 (10:20 pm)

      It’s very cool.  You should ask for a tour.

    • Daniel January 24, 2024 (11:05 pm)

      Indeed, that’s some super cool engineering and construction.

  • Alki res January 24, 2024 (10:04 pm)

    Very cool! Thanks for sharing this information.  Incredible that it only takes one person to operate normally.

  • Always A Bridesmaid January 25, 2024 (7:17 am)

    Very cool indeed. What about the landscape around the facility? Sad there’s no mention of it. Is it functional to cleansing and/or storing water, or is it an educational demonstration landscape? It feels this celebration snubbed the landscape architecture of this amazing project, like it’s the Greta Gerwig of stormwater management. 

    • WSB January 25, 2024 (11:22 am)

      Hi, this wasn’t the grand-opening celebration – that happened a year ago. (We unfortunately weren’t able to go then, which is part of the reason why this tour opportunity was appealing.) Perhaps they talked about landscaping then. If you listen to the second video clip (both clips are only a couple minutes long), Rebecca Singer does mention the primary landscaping feature I noticed, permeable “paving” (grass growing between open blocks) all over the site – you can see it under and behind her in the video. I also noted an interpretive plaque by a seating area with what I think was a bioswale (not filled so hard to tell) – TR

  • Plastics? January 25, 2024 (8:09 am)

    Are they still using plastics to condition and form the fertilizer? Or do they have a different process now?  I worry about the chemical contamination of farmland that this could cause. Recycling is nice, but protecting our food from chemical contaminants is more important.

  • KayK January 25, 2024 (9:55 am)

    Any mention of the public art component?

    • WSB January 25, 2024 (10:55 am)

      They talked about the “flowing” lights but it was daylight so we couldn’t see a demonstration. We weren’t able to attend the grand opening a year ago – this was sort of an update event rather than a thorough explanation of everything – TR

  • Another One January 25, 2024 (12:28 pm)

    A friend of mine saw this fertilizer spread around. He said it was full of the grocery code stickers they put on produce. So many little stickers. Do people just eat those stickers? 

    • WSB January 25, 2024 (1:31 pm)

      The stickers are supposed to be thrown away in the garbage, so they shouldn’t be turning up in other streams …

  • Nearby Worker January 25, 2024 (4:59 pm)

    Although I accept that the solids are removed and sterilized, I have to wonder about the heavy metals and other chemicals in them and the agricultural use indicated.  Much of that area is industrial and contaminated.

  • General Info January 26, 2024 (9:48 am) The above has more info on how King County addresses industrial waste

Sorry, comment time is over.