Kingston sewage plant to study uses of treated sewer water
September 15, 2008 · Updated 11:10 AM
KINGSTON — The Department of Ecology recently awarded Kitsap County $200,000 to see if Kingston residents’ sewage wastewater can be reused.
Additional treatment would enable reused wastewater to supplement stream flows in Grovers Creek, irrigate fields in North Kitsap’s Heritage Park and recharge aquifers, said Stella Vakarcs, acting senior manager for sewer utility for Kitsap County Public Works. Currently, North End residents get their drinking water from aquifers.
“The feasibility grant is for upgrading the treatment facility at the Kingston Treatment Plant to a Class A level. Now, they only treat to a Class B so the water can be discharged into the Sound,” Vakarcs said.
All the water that flows freely in sinks, bathtubs and toilets in North End homes is treated and released into the Puget Sound, said Don Johnson, operations foreman at Kingston’s wastewater treatment plant.
Before it is released in an outfall near Appletree Cove, microorganisms, bacteria, oxygen and ultraviolet light treat the sewage water at the plant located on South Kingston Road.
In accordance with the grant money, a separate treatment system will be built and additional wetlands constructed.
“Additional treatment is necessary to get to a Class A to discharge (treated water) into the wetlands out there,” she said, adding wetlands naturally filter water through gravel and silt before it soaks into the groundwater.
Currently the plant has no treatment system set up for Class A, said Johnson.
“(Class A) is beyond our scope. It takes another step in treatment which is beyond the existing capability of this plant,” he said. “Someone will need to design and have it built. Clearly the feasibility study is very much at the beginning.”
Hundreds of gallons of water are pumped from underground aquifers daily to North End residents’ homes. About 114,000 gallons of wastewater come through the treatment plant every day, adding up to more than 41 million gallons annually — all enter the Sound, Johnson said.
Although there is no immediate threat of a water shortage, growth creates hazards to aquifer recharge, said Bob Hunter, assistant manager of Kitsap Public Utility District, as rainwater can’t seep through housing’s impervious structures.
To put growth into perspective, in 1986 when Hunter first started with KPUD there were 3,000 customers. Now there are more than 14,000 customers — 5,000 are in the north peninsula water system.
“The greater need for (water reuse) is so that we don’t have our outfalls in the Puget Sound,” Hunter said.
“KPUD is all for reuse. It’s probably best for the environment but at the same time they have to balance the budget,” he said, referring to the cost of the pilot project and additional treatment.
Reused water to help creek, park
Although the project is in its infancy, Vakarcs said if all goes as hoped, the treated water could help irrigate Kingston’s Heritage Park and supplement the trickle of water in Grovers Creek. The creek is an important salmon habitat and home to Suquamish Tribe’s Grovers Creek Salmon Hatchery.
Keith Folkerts, natural resources coordinator for Kitsap Department of Community Development (DCD), said the least expensive way for the county to water Heritage Park is to drill a well.
Heritage Park sits in the same drainage basin as the creek, which is currently closed to future surface water diversions and unmitigated groundwater withdrawals due to the diminished creek flow.
“Grovers Creek doesn’t meet the minimum requirements for flow for the habitat and the overall health of the stream,” Vakarcs said.
The only way to drill a well in the area is through mitigation, Folkerts said.
“If we did drill a well it would have some impact on Grovers Creek. The park is within the same drainage basin and by laws of gravity it would have an effect. One way to mitigate is by taking water from the treatment plant and then pumping it to the drainage basin to restock Grovers Creek,” he said, adding the system would restock the creek with more reused water than it could be taking away in the well.
According to Kitsap’s Reclaimed Water Report submitted September 2007 to the DCD, minimum flows in Grovers Creek are not met between June and October.
Delivery of the water to the creek would increase the streamflow by 16 percent, meeting the minimum flow for most summer months, the report states.
The report proposes that three quarters of the total capacity of the plant — 300,000 gallons per day — could be allocated to augment the creek.
This number is feasible but includes projected growth estimates and future residents of Arborwood Development, Johnson said.
“Treatment facilities are designed and built with future growth in mind,” he said.
Reuse costs more initially, less overall
Folkerts said wastewater reuse projects like the one proposed for Kingston are popping up all over the world.
“We take this valuable resource and treat it as a waste now but communities throughout the world, especially the West, are looking at ways to put it to good use again,” he said. “This will certainly reduce the amount of everything from the pharmaceuticals to the nutrients going into the water ... . Obviously there’s significant treatment going on now and it’s closely monitored but this would reduce it even more.”
After the grant funding is used up, costs to continue the program would have to be worked into the operation and upkeep of the plant, he said.
According to the Reclaimed Water Report, total program costs are an estimated $3.6 million. Over a 30-year period, monetary benefits are estimated between $3.1 and $3.9 million.
“The proposed program would provide the county with a fully functional water reclamation facility and a reliable water supply for the North Kitsap Heritage Park.”
The report states these benefits alone could provide a net benefit of $600,000.
Port Orchard two steps ahead of Kingston
Larry Curles, general manager for West Sound Utilities in Port Orchard, said a feasibility study for a reuse wastewater treatment system already took place in his utility district. Now the utility is working on implementing a system to make it happen.
“Next year we are actually going to start putting money into pipes to Veterans Memorial Park,” he said.
West Sound Utilities runs 1.7 million gallons a day of potential fresh water into the Sinclair Inlet, he said.
“That water has the potential to help with our urban stream,” he said. “We are wasting more than 1 million gallons of fresh water a day in treatment. In a perfect world every drop of water treated can be used.”
When asked about future cost to customers, Curles said his goal is to have it be less expensive than groundwater, although being able to pump reused water to individual homes is years out.
“Anything important or of value will cost,” he said. “We are going along very carefully and methodically.”