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What we do

WTD is an innovative clean-water enterprise that protects public health and water quality by providing wholesale wastewater treatment services to 17 cities, 17 local sewer districts and more than 1.6 million residents across a 420-square-mile area in King, Snohomish and Pierce counties.

More than 650 WTD employees manage the regional system of treatment plants, pipelines and pump stations that operate around the clock. They also plan and design new facilities, regulate the disposal of industrial waste, educate the public and businesses on pollution prevention, and pursue innovation by recycling resources to support sustainable communities.

2016 accomplishments

Plant operation

West Point Treatment Plant celebrated 50 years of service. Regional wastewater treatment has cut pollution to the Duwamish River, and transformed Lake Washington to one of the world’s cleanest urban lakes.

All five treatment plants attained 100 percent compliance in meeting state and federal effluent limits. Vashon Treatment Plant earned a platinum level award for compliance with all permit conditions over a period of five consecutive years.

Brightwater Treatment Plant earned the Department of Ecology’s “Outstanding Wastewater Treatment Plant” award, which is only given to facilities achieving perfect performance in a reclaimed water process that depends on compliance from operations to its customers.

Resource recovery and recycling

Between West Point and South treatment plants, WTD produced 33,600 megawatt hours of electricity, enough to power nearly 4,000 homes.

In addition, WTD cut electricity usage by 800,000 kilowatt hours by installing programmable thermostats in six pump station HVAC systems. Once all pump stations are equipped, the division expects to reduce offsite electricity by 10 percent.

One-hundred percent of the division’s Loop® biosolids were recycled for use in forestry, agriculture and commercial composting applications.

Education, outreach, and community services

WTD continues to promote education about clean water systems and careers in diverse communities. The division hired 10 high school students for an internship learning about water systems, equity and social justice, and careers in wastewater.

WTD’s project team working on the Georgetown Wet Weather Treatment Facility completed a design advisory group effort.

This year marked the five-year anniversary of WTD’s partnership with IslandWood that has reached almost 60,000 people through clean-water education programs.

Pollution control and cleanup

In July, King County approved 11 WaterWorks Grant Program awards to address water quality issues. The City of Kent’s Leber Homestead Arsenic Remediation Project led to completion of off-channel salmon habitat and floodwater storage.

In the fall, King County participated in the “Make a Difference Day” planting event at the Georgetown Green Wall, a community driven air quality project funded by WTD’s Green Grants Program.

WTD’s Murray Wet Weather Storage Facility began operations in November. This facility protects Puget Sound by reducing untreated discharges of stormwater and wastewater off Lowman Beach Park in West Seattle during heavy rainstorms.

WTD led the design and contracting for exploring cleanup technology for the Lower Duwamish Waterway Group, including testing activated carbon for sequestering pollutants.

Finance and administration

Excellent credit ratings and continued favorable financial market conditions combined  to benefit ratepayers served by WTD. King County sold $500 million of sewer revenue bonds in September, essentially re-financing its debt to save $104 million over the next 33 years.

WTD maintained a strong sewer revenue bond rating with sound management practices and consistent financial performance.

WTD received recognition by the “Utility of the Future-Today Joint Recognition Program,” which is supported by the U.S. Environmental Protection Agency. WTD was one of 61 recipients recognized nationally for optimizing operations, meeting or exceeding regulatory requirements, and engaging employees and communities.

Capital projects

The division invested about $207 million in capital improvement projects to add system capacity, replace or rehabilitate aging facilities, and enable efficient operations.

The Fremont Siphon Replacement Project was completed and includes two new pipelines tunneled under the Lake Washington Ship Canal to replace World War I-era pipes.

The RainWise partnership between King County and the City of Seattle marked the 1,000th installation of green stormwater features on private property that will reduce annual stormwater runoff by up to 16 million gallons.

Outlook

The division will maintain its commitment to service excellence by increasing efficiency through Lean and continuous improvement; meeting or surpassing permit requirements; exploring new technologies and markets for its recycled products; restoring the West Point Treatment Plant; and investing in its asset management and capital improvement programs.

2016 annual report coverEnvironmental Stewardship in King County, 2016

"Environmental Stewardship in King County," the 2016 annual report for King County Department of Natural Resources and Parks, describes the department, what it was tasked to do, and what it accomplished in 2016.

Celebrating 50 years of work to keep our waters cleanWTD celebrated the men and women who have dedicated their careers to clean water service.

1610_utility-of-futureActing Director Gunars Sreibers and Assistant Director Sandy Kilroy celebrate the people and energy that earned WTD’s recognition. 

crane-rosette-with-CTC-sampling-bottles_600The County’s marine water quality monitoring program collects and analyzes water quality samples at 12 offshore sites and 20 beach locations.

What we do

WTD is an innovative clean-water enterprise that protects public health and water quality by providing wholesale wastewater treatment services to 17 cities, 17 local sewer districts, and more than 1.6 million residents across a 420-square-mile area in King, Snohomish, and Pierce counties.

The division’s 630 employees manage the regional system of treatment plants, pipeline, and pump stations that operate 24/7. They also plan and design new facilities, regulate the disposal of industrial waste, educate the public and businesses on pollution prevention, and pursue innovation by recycling resources to support sustainable communities.

2015 accomplishments

Plant operation

All five treatment plants attained 100 percent compliance in meeting federal and state effluent limits. The Vashon, Carnation, and South treatment plants earned the Washington State Department of Ecology’s “Outstanding Performance Award” for perfect compliance with all permit conditions in the prior calendar year.

The division completed negotiations with the state Department of Ecology to renew the National Pollutant Discharge Elimination System permit for West Point Treatment Plant.

Resource recovery and recycling

The 2015 drought brought new focus on the division’s recycled water program. Under new agreements, WTD supplied recycled water from its Brightwater Treatment Plant to the Lake Washington Youth Soccer Association’s fields at 60 Acres Park and to the City of Kirkland for municipal uses.

The division sought approval from the Utilities and Transportation Commission to transport biomethane gas from South Treatment Plant to filling stations for compressed natural gas vehicles, which will be an additional revenue source for WTD’s energy products.

One-hundred percent of the division’s Loop® biosolids were recycled for use in forestry, agriculture and commercial composting applications, and demand for this nutrient-rich resource remained strong.

Education, outreach, and community services

Environmental education remains popular with schools and community members. In 2015, WTD guided more than 15,000 people through Brightwater’s exhibit hall, as well as tours, lectures, and workshops. The division also pilot tested a high school internship program to interest local youth in wastewater careers.

Pollution control and cleanup

In 2015, WTD met compliance schedule requirements and project milestones for its Combined Sewer Overflow Control Program by completing construction on projects in Magnolia, North Beach, and West Seattle to control overflows that occur during heavy rains.

In 2015, WTD awarded $100,980 in funding to Duwamish-area community projects through its Green Grants program. The grants were part of a settlement agreement with Puget Sound Clean Air Agency to resolve issues stemming from the West Point Treatment Plant’s raw sewage pump engines.

WTD continued its engagement with EPA, City of Seattle, Port of Seattle, and Boeing on the Lower Duwamish Superfund Cleanup.

Finance and administration

Solid credit ratings and favorable financial markets continued to benefit WTD’s ratepayers and customers. The division refinanced $728 million in bonds that will save $160 million over the next 30 years, and secured $105 million in new funding for its capital program at the lowest interest rate since the 1960s.

Moody’s and Standard & Poor’s affirmed their respective ratings of WTD’s sewer revenue bonds at Aa2 and AA+, citing the utility’s strong management practices, consistent financial performance and bright regional economic outlook.

In December, the Washington State Court of Appeals affirmed a 2012 jury verdict awarding King County $144 million in damages and attorney’s fees after finding a Brightwater tunneling contractor defaulted on key contractual obligations, which will mean less borrowing to fund future projects.

The County Council adopted a monthly wholesale sewer rate of $42.03 through Jan. 1, 2017, which is unchanged from the rate adopted in June 2015. The capacity charge levied to newly connecting customers was raised for inflation from $57 to $58.70.

Capital projects

The division invested $170 million in capital improvement projects to add system capacity, replace or rehabilitate aging facilities, and enable efficient operations.

WTD completed the Barton Pump Station Project in West Seattle. New capacity and electrical and pumping equipment will improve service while protecting the environment from overflows of stormwater and sewage during heavy rains.

Work continued on the North Creek Interceptor Project to replace and rehabilitate nearly two miles of aging sewer line in Bothell and construction began in Fremont to replace an aging siphon beneath the Lake Washington Ship Canal.

Construction is wrapping up on a new 48-foot environmental research vessel that will enable research scientists to more efficiently collect vital data needed to protect Puget Sound, Lake Washington, and the Duwamish River

Outlook

In 2016 and beyond, the division will maintain its commitment to service excellence by increasing efficiency through Lean and Continuous Improvement, meeting or surpassing permit requirements, exploring new technologies and markets for its recycled products, and investing in its asset management and capital improvement programs.

Environmental Stewardship in King County, 2015

"Environmental Stewardship in King County," the 2015 annual report for King County Department of Natural Resources and Parks, describes the department, what it was tasked to do, and what it accomplished in 2015. The report provides maps, facts, and figures to convey the breadth of department responsibilities and includes overviews of executive initiatives, performance measures and results, and awards won by the department in 2015.

2015_page16-17_300Mission – King County’s Wastewater Treatment Division protects public health and enhances the environment by collecting and treating wastewater while recycling valuable resources for the Puget Sound region. 

rainwise_300Al Noor Mosque in White Center celebrated completion of a rain garden and cistern project funded by WTD’s RainWise program partnership with Seattle Public Utilities. The program supports the reduction of combined sewer overflows.

Barton-roadside-raingardens_300WTD completed its first major green infrastructure project in West Seattle, installing 91 roadside rain gardens to support its goal to control overflows of stormwater and sewage into Puget Sound during heavy rains.