King County wants to renegotiate a high-stakes court settlement to curb discharges of untreated storm and wastewater that may overflow sewers during heavy rainfall, citing challenges ranging from soaring construction costs to climate change.

The county expects to spend some $1.9 billion on this work during the next decade. But county officials now want regulators with the state Ecology Department and federal Environmental Protection Agency to give them more time to complete some projects, and agree to a broad review of how the money should best be spent.

“We are willing to invest money, substantial amounts of money, to make water quality better here,” said Christie True, director of the county’s Department of Natural Resources. “What we’re really keying up here is, what are the best things that we could do with the money that we have?”

True said it could take two years to conduct scientific studies and come up with a plan that could better address the huge amount of stormwater that regularly bypasses treatment facilities, incidents which are far more frequent than the more dramatic, but rarer, overflows of sewage facilities that can follow heavy storms.

A 2018 county technical memorandum that analyzed stormwater runoff found that that the untreated discharges from the combined sewer-storm system totals about 595 million gallons.

In contrast, the county estimates that 118 billion gallons of untreated stormwater flows from a separate network of ditches and pipes that enter the region’s streams, rivers and estuaries and can carry chemicals, oil, lubricants, animal waste, copper and other contaminants that can harm aquatic life.


The current county spending is guided by a 2013 consent decree filed in U.S. District Court. The 72-page settlement lays out a series of timelines stretching to 2030 for improvements in the network of sewers that carries a combination of human waste and stormwater.

In an Oct. 28 letter letter to state and federal regulators, King County formally requested a new round of negotiations to modify the agreement on how to improve the quality of the water that treated — or untreated — eventually flows to Puget Sound.

The new letter notes that nine projects outlined in the consent decree had previously been estimated at $849 million. Today, four of those projects are in some stage of design, construction or completion, but the estimated cost for the remaining five is now more than double the initial estimate for all the projects combined.

“These cost estimates will only continue to escalate due to climate change, the difficulty of finding locations for facilities in a dense urban area and the associated needs for more pumping and conveyance,” says the letter from Mark Isaacson, director of King County’s Wastewater Treatment Division.

Climate change is projected to lead to increased rainfall which will require more capacity to handle runoff.

State and federal officials have agreed to talk about possible changes to the consent decree, with an initial meeting scheduled for Jan. 8.


The meeting also will include Seattle city officials, who entered into a separate settlement agreement to reduce discharges, and also have requested additional time to reach the work deadlines.

Ecology Department spokeswoman Colleen Keltz said both King County and Seattle officials have made reasonable requests, and “there may be more room for flexibility” with respect to specific projects and timelines. But she said the overall requirement of bringing the combined stormwater-sewer systems into compliance with federal and state law will remain unchanged.

Most of the time, this system is able to handle all flows and carry them to treatment plants. But during intense storms they may overflow, and the 2013 consent decree resulted from a complaint filed by regulatory officials alleging these discharges repeatedly violated federal Clean Water Act standards.

Six years later, the county continues to struggle with compliance. Just last month, the county was hit with a $105,000 fine for 18 violations of pollution limits during a two-year period from four plants built to treat the sewer and stormwater overflows.

Despite such penalties, True said the county has made tremendous progress in reducing the overflows from the combined sewer-stormwater system.

The county and Seattle Public Utilities are currently building a massive sewage and stormwater tunnel between Ballard and Fremont along the Lake Washington Ship Canal, whose cost has swelled to $570 million. That project is estimated to reduce pollution sewage and stormwater overflow from 90 million gallons a year to 8.5 million gallons. A $262 million treatment plant in Georgetown that will cut untreated stormwater discharges into the Duwamish River from 130 million gallons annually to less than 10 million also is under construction.


Some veterans of stormwater cleanup say such projects do deliver substantial benefits, since these discharges may include concentrated doses of sewage that are very high in bacteria.

“They are having real impacts on the things that we care about,” said Mindy Roberts, a former state Ecology Department official who now works for the Washington Environmental Council.

County officials want to consider a broader array of work to reduce pollution. The goal would be to give the biggest possible boost to efforts to recover salmon, southern resident orcas and other Puget Sound marine life. Some options could be more business inspections to improve pollution control, more street sweeping, more tree planting. There could also be more landscaped drainage channels called bioswales that help to absorb pollution and more treatment of sediments that have been contaminated.

“What we would be looking at is really trying to find things that would have the same or better amounts of pollution reduction,” True said.