King County warns Ecology nutrient plan could cost $10–$20 billion and urges collaborative, science-based approach

King County wastewater officials told the Regional Water Quality Committee on Sept. 3 that Washington State Department of Ecology's draft nutrient reduction plan and voluntary general permit could require one of the largest water-quality investments in state history and will need more collaborative work before it is finalized. "Upgrading King County's wastewater treatment system could cost on the order of $10 billion to $20 billion or more measured in today's dollars," Director Cameron Gural of the Wastewater Treatment Division said, calling the investment "very expensive" and saying it would take decades to implement.

Gural said the division submitted detailed comment letters to Ecology on Aug. 27 and recommended changes to the draft plan and permit. He told the committee that King County supports the "mechanism" of a permit-based approach but raised concerns about technical assumptions, timelines and cost estimates. He said Ecology appears to be using load targets and water-quality standards that the county believes need stronger scientific justification and suggested a biologically based approach that would account for species needs and natural variability in Puget Sound.

Why this matters: County staff said the proposed load targets use 2014 baseline data and do not account for growth since then, which could make the targets harder to meet as populations increase under the State Growth Management Act. The county warned regulators and local leaders that meeting the draft targets would raise rates on households and businesses and pose technical challenges for large plants, particularly West Point, where Gural said maintaining treatment operations while constructing upgrades will be complicated.

In his presentation, Gural recommended that Ecology work collaboratively with regulated utilities to (1) re-evaluate the water-quality standards used to set targets, (2) incorporate scientific uncertainty with an adaptive-management approach, (3) reconcile differences across Ecology's own documents with utility input, (4) ensure planning reflects climate-change effects, and (5) consider the cost and energy implications of potential treatment approaches. "We are committed to continue to work with Ecology, other utility partners, and others, like tribes and NGOs, to work towards better consensus on this important topic," Gural said.

Committee members pressed staff on the numbers and on trade-offs between projects. Commissioner Warren said the scale of the nutrient costs made other large projects — such as combined sewer overflow controls like the mouth of the Duwamish project — harder to justify without better comparative science. "Does it make sense to spend $3 billion on CSO control when we've got to spend $20 billion on nutrients?" Warren asked, urging analysis of relative impacts.

Gural and staff reported coordination with peer utilities through a Utility Caucus and the Association of Washington Cities and said King County had asked the National Association of Clean Water Agencies (NACWA) to examine national examples to learn how to structure cost-effective, consensus-based programs. Gural also noted that the county's South Plant recently received a NACWA platinum peak performance award for five years of 100% permit compliance.

What’s next: County staff said they will continue to work with Ecology and peers, participate in proposed technical advisory committees, and refine the county's comments. The county also said more detailed briefings are scheduled for related subcommittees and for next steps in the Regional Wastewater Services Plan work.

Authority: The county's comments were made in response to Ecology's draft nutrient reduction plan and voluntary general permit and were submitted Aug. 27. The committee discussion referenced ongoing litigation and the county's internal capital and rate planning documents.