Recycled waste water to be used for irrigation

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Golf fairways and farms in the green Sammamish River Valley could soon be irrigated with recycled waste water instead of taking fresh water out of the salmon-bearing river nearby.

King County Executive Ron Sims yesterday announced plans to build a small sewage-treatment plant in the valley by 2003 and a smaller test project this summer.

Sewage from a large pipeline in the valley would be diverted into the new plant, where solids and water would be separated. The solids would be reinserted into the pipeline and complete their trip to the county's regional treatment plants. At least 3 million gallons of treated water per day could be piped or trucked to nearby lands.

Sims called the end product "a new, drought-proof supply of water."

The county is negotiating with potential users, including the Willows Run Golf Course, Molbak's, FARM (Farm Acquisition, Research and Management) and other local farmers.

County officials say reclaimed water will meet state Health and Ecology department "class A" standards, clean enough to be applied on crops.

FARM manager Roger Calhoon said he needs more information before deciding whether to apply recycled water to cherries, corn, pumpkins, apples and other produce.

"I'm concerned not just about microbial contamination but organics, fertilizers, heavy metals coming through," he said.

Among other treatment steps, a membrane will screen out contaminants "at the molecular level," said Tom Fox, the county's water-reclamation manager.

Recycled water is routinely used on California farms and on Walla Walla sweet onions, said Washington state Department of Ecology spokeswoman Mary Getchell.

"You probably eat food every day that was grown with reclaimed water," she said.

The recycling plant, at $20 million and half the size of a soccer field, is intended to reduce the valley's consumption of Sammamish River water and valley ground water by one-third or more.

The test project will be next to the river at Northeast 124th Street between Redmond and Woodinville. A site for the larger facility hasn't been chosen.