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Ewa plant
to recycle
waste water
The plant will turn out
By Suzanne Tswei
12 million gallons of water
each day for irrigation and energy
Star-BulletinTo see a beaker of discolored, musty-smelling water in Ken Windram's hand isn't the surprise. Dirty water has been the veteran waste-water treatment expert's cup of tea, so to speak.
The surprise is the beaker of crystal-clear water he's holding in the other hand.
"This is super-clean water. It's super, super clean -- cleaner than the water you drink. That's what we do here," Windram said.
As project manager of Ewa Water Recycling, Hawaii's newest and biggest waste-water recycling plant, Windram will be in charge of turning 12 million gallons of waste water into usable water for Ewa every day. None of the recycled water will be for drinking -- even the "super-clean" water, which is ideal for industrial use but not for human consumption, Windram said. Although it's possible to produce drinking water from waste water, there are no such plans for Hawaii.The plant is under construction adjacent to the city's Honouliuli Wastewater Treatment Plant, and is scheduled to open Aug. 8. It is a joint venture by the city and USFilter, which is paying for the project. USFilter is the American branch of the French firm, Vivendi, the world's largest water company that does everything from bottled water to waste-water treatment.
The recycling plant will use waste water from the Honouliuli plant, which collects raw waste water, removes the solids and discharges the treated water into the ocean.
"That's perfectly good water that we are throwing away," Windram said, pointing to the beaker of yellowish water. "It may not look very appetizing ,but it can be treated and put back into the system. To take that waste water and put it through further treatment, we can conserve our very precious resource -- fresh water.
"That's what I like. We will be saving millions of gallons of fresh water every day," Windram said.
Ewa Water Recycling will use treated waste water to produce two kinds of cleaned water: 10 million gallons a day of disinfected water that retains minerals and nutrients that make it ideal for irrigation, and 2 million gallons of "super-clean water" to be used in power plants and refineries to produce electricity and steam.
"The super-clean water is what sets us apart from the pack," Windram said, noting Hawaii has had a number of waste-water recycling plants producing irrigation water.
"The technology to make the super-clean water for industrial use has been available and has been in use elsewhere. But it's never been done here. We are the first to bring the technology to Hawaii," he said.
The "super-clean water" is suited for industrial use because it is without minerals, which can leave a residue or scale in boilers. Drinking water should contain these minerals, which are necessary for the human body.
The recycling plant's future customers, Kalaeloa Co-Generation Plant, AES Hawaii and Tesoro Hawaii, have to produce their own industrial-quality water from tap water. They will receive their supply through underground pipes when the plant starts production.
"What we are saving is perfectly good water from the tap that people need for drinking, bathing, washing. Millions of gallons of tap water are being used for industry and irrigation when we can use recycled waste water for the job," Windram said.
The plant will make "super-clean water" by running the waste water through microfiltration units, which trap solid material with tubes packed tightly with strands of synthetic threads. Then the water will be forced through a set of membrane filters, the reverse osmosis units, to remove dissolved minerals like calcium, iron and sodium.
The reverse osmosis water will be stored in a 1.5 million-gallon stainless-steel tank to be pumped to the industrial customers.
To produce water for irrigation at nearby golf courses and green spaces, the waste water will go through a different set of treatments, including ultraviolet light disinfection to ensure disease-causing bacteria are destroyed.
The irrigation water will be stored in two glass-lined steel tanks, each capable of holding 2.5 million gallons. This water also will be piped to customers through underground pipes.
USFilter, which will turn the plant over to the city after 20 years, is spending $38 million to build the plant. The company also will pick up the annual $1 million in operating costs.
The recycling plant will sell its water to recoup the costs and use the plant as a model to attract customers in Asia and the Pacific, Windram said. The plant will charge $1.15 per 1,000 gallons of irrigation water and about $5 per 1,000 gallons of industrial-quality water.
The plant helps the city satisfy a 1995 consent decree that resulted from lawsuits filed against the city over sewage spills and other problems, he said. As part of the consent decree, the city agreed with the federal Environmental Protection Agency to establish a water reuse program.
Water data
Waste water processed at Honouliuli Wastewater Treatment Plant: 40,750,294 gallons in 1999
