Community, King County celebrate completion of Carnation wastewater treatment plant

State-of-the-art facility will mean a safe environment, growth for community

Carnation community members came together today to celebrate the completion of their new wastewater treatment plant – a facility that protects local water quality and helps ensure future growth in the region.

Complete with live music, speeches and a salmon barbecue, the celebration signaled the successful conclusion of a collaborative effort between local, county, state and federal agencies who share a common goal: Protect the environment while ensuring the community can continue to thrive.

“Replacing old, failing septic systems with a new, state-of-the-art treatment plant will protect this beautiful Snoqualmie River and all the creatures that love and depend on it,” said King County Executive Ron Sims at today’s dedication ceremony. “Carnation’s future environmental and economic goals are ensured, thanks to this facility.”

Sims gave special thanks to U.S. Rep. Dave Reichert, who attended today’s ceremony, and was responsible for securing $1.3 million in federal grant funding for the $23 million project. County and state grant funding was also used during the construction project, which took less than two years to complete.

The plant will treat wastewater to such a degree that highly reclaimed water will be used to enhance a wetland at Chinook Bend Natural Area, a mile and a half north of the Carnation plant.

The Carnation Wastewater Treatment Plant uses an advanced treatment technology called a membrane bioreactor (MBR) system instead of the large round settling tanks used in conventional plants. The membranes are immersed in wastewater. The MBR system sucks wastewater through hollow fibers with microscopic pores small enough to filter out particulate matter and even individual bacteria.

In addition to the reclaimed water, the plant has been designed with numerous “green” features that minimize impacts on the environment, conserve resources and maximize energy efficiency.

For example, regionally available materials and materials with recycled content were used during plant construction, and construction waste was recycled whenever possible. Energy and water efficient equipment was installed throughout the plant, and the building was designed to take advantage of natural light for indoor spaces.

The new treatment plant will serve about 2,000 people in Carnation’s urban growth area, with capacity to serve up to 4,000 in 2030. At design capacity, the plant is expected to treat 480,000 gallons of wastewater a day.

The water quality of the plant’s effluent – the treated wastewater leaving the plant – is regularly tested. During the start-up phase, treated water from the plant will be discharged via the river outfall at Carnation Farm Road Bridge, but flows will eventually be directed to the Chinook Bend wetlands along the Snoqualmie River.

Using the membrane bioreactor technology will also allow for expanded use of reclaimed water that can be used for irrigation and wetland enhancement. Sims said King County partnered with Ducks Unlimited to enhance the Chinook Bend wetlands, which provide highly prized habitat for fish and wildlife.

“The wastewater will be seven to 10 times cleaner than typical secondary treated wastewater,” Sims said. “By reducing the discharge of pollutants even more with the MBR process, we’ll provide an even higher level of protection for the Snoqualmie River and surrounding environment.”

Today’s dedication ceremony included live music by Duvall’s Cedarcrest Jazz Band, and a salmon dinner hosted by the Snoqualmie Tribe.

Speakers included Carnation Mayor Mike Flowers; Congressman Dave Reichert; County Councilmember Kathy Lambert; State Reps Larry Springer and Roger Goodman, and Snoqualmie Tribe Drum Bearer Ray Mullen.

The treatment plant is located at 4301 Larson Ave. in Carnation. For more information about the project, visit http://dnr.metrokc.gov/wtd/carnation/index.htm.

People enjoy clean water and a healthy environment because of King County's wastewater treatment program. The county’s Wastewater Treatment Division protects public health and water quality by serving 17 cities, 17 local sewer utilities and more than 1.4 million residents in King, Snohomish and Pierce counties. Formerly called Metro, the regional clean-water agency now operated by King County has been preventing water pollution for more than 40 years.

Related Links

 Video: Newest wastewater treatment facility opens in Carnation

Carnation Wastewater Treatment Plant

King County Wastewater Treatment Division