King County’s Sewer Rate Hike Is Now Official — Here’s What the Council’s Own Numbers Show

Seattle Sewer & Utility News

Seattle, WA — July 3, 2026 | By The Drain Authority

The King County Council voted unanimously on June 23 to approve a 12.75% sewer rate increase for 2027, locking in what had only been a proposal when we covered it two weeks ago. The wholesale monthly sewer rate is now set to rise from $62.66 to $70.65 starting January 1, 2027 — and council members used the vote to warn that this is not a one-time bump. Under the county’s own forecast, rates could nearly double again by 2032.

What the council actually approved

The increase passed the King County Council with no dissent, raising the county’s wholesale monthly sewer rate — the wholesale charge that funds regional treatment, not any individual city’s local sewer bill — to $70.65 for 2027, according to King County’s official rate page. That’s about $8 more per month, or roughly $96 a year, for the average Seattle-area household’s wastewater treatment portion of their utility bill. The approved increase is projected to generate $676.2 million in revenue for the Wastewater Treatment Division next year, according to reporting from KIRO 7 News.

The money is going toward roughly $6.2 billion in capital projects tied to aging infrastructure — much of the regional system has been running nearly continuously since the 1960s — plus federal and state regulatory deadlines for reducing combined sewer overflows.

Council members are already worried about what comes after 2027

What’s notable about this vote isn’t just that it passed — it’s how bluntly the council talked about the trajectory it’s now locked into. “We are in violent agreement across this council and our partner jurisdictions that the wastewater treatment rates are going up at an alarming trajectory, and it is not sustainable,” said Councilmember Claudia Balducci, who represents the Eastside and sits on the Regional Water Quality Committee. Council Chair Sarah Perry, who represents Duvall, Issaquah, and Woodinville, echoed the point: “I don’t view rate increases of this magnitude as sustainable.”

Their concern is backed by the Wastewater Treatment Division’s own multi-year forecast. If the current plan holds, double-digit increases continue for several more years before leveling off:

Councilmember Ron Dembowski, who represents Bothell, Kirkland, and North Seattle, said the reaction from constituents has been visceral. “When I shared that with a group of constituents in Wedgwood at a neighborhood meeting, the jaws dropped, jaws dropped, and gasps were heard,” he said. Councilmember Steffanie Fain, who represents Des Moines, Kent, and Renton, pointed to a recent council visit to the South Treatment Plant as a reminder of the scale of the problem: “That reinforced for me the importance of these investments and the scale of the challenges ahead.”

The angle most coverage is missing

Every outlet that’s covered this vote has led with the same number: $8 more a month starting in 2027. What’s gotten almost no attention is that seven-year table above, and what it actually means for a homeowner’s budget. If the county’s forecast holds, the wholesale rate alone goes from $62.66 to $125.92 — essentially doubling — in the same window most Seattle homeowners plan a kitchen remodel or a roof replacement around. That’s not a rounding error. It’s a structural, compounding cost increase on the part of your utility bill you have zero control over.

Which makes the part you do control worth more attention, not less. As we noted when the proposal was first transmitted, the side sewer line connecting your home to the street isn’t touched by any of this money — it’s entirely the homeowner’s responsibility, the same way it’s always been. But with the treatment side of the bill on a trajectory to double, the math on deferring maintenance on your own line shifts. An emergency sewer backup already costs more than a scheduled repair; now it’s competing for the same household budget against a regional utility bill that’s rising 12%-plus a year with no ceiling in sight through 2032.

What this means if you own an older Seattle-area home

You can’t vote on the county’s rate schedule, but you can control whether your own line is the next expensive surprise layered on top of it. If your home has original clay or cast-iron piping — common across Seattle’s older neighborhoods — pipe descaling can strip years of mineral and grease buildup and meaningfully extend the life of a line that’s already decades old, often for a fraction of the cost of replacement. It’s the kind of proactive move that makes more financial sense every year the regional rate climbs.

If you’re not sure what condition your own line is in, that’s the place to start before the next rate notice arrives. Browse our full list of Seattle drain and sewer services or get in touch to schedule an inspection before a small problem turns into an emergency one.

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Sources: King County Wastewater Treatment Division — Sewer Rate and Capacity Charge; KIRO 7 News / MyNorthwest.com, June 25, 2026.