More untreated wastewater discharged into Puget Sound

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SEATTLE -- Between six and 10 million gallons of untreated wastewater flowed into Puget Sound on Wednesday. It's the second time in less than a week.

Last week, heavy rain flooded the West Point plant at Discovery Park. Equipment failures forced the plant into emergency bypass mode, sending 200 million gallons of wastewater into Puget Sound.

"Our digesters, which treat the solids, are all offline in that area," explained Mark Isaacson. "We were hit with a wall of water about 2:30 in the morning. Mother Nature delivered a tremendous amount of water to us and Mother Nature won. It overwhelmed the plant."

Since then, crews have worked to repair the damage, but right now the plant is only operating at half capacity. That's why more rain Wednesday morning forced more wastewater into Puget Sound.

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About 90 percent of the discharge is storm water run-off. The remaining 10 percent is raw sewage.

"If we didn't do that again, the entire plant would've been flooded. We passed about 6-10 millions from 3:30 this morning through the emergency bypass gates out into the Sound. We stopped that about 10:30 when the rain and the flows subsided," Isaacson said.

Isaacson says this is a first for the plant. In several decades of operation, it has never had a failure of this magnitude.

It will likely take crews several weeks to restore the plant. That means, on rainy days, it's possible wastewater overflows will continue.

"Short events like this, much to our dismay, they occur. In the big picture, we'll recover. We'll get this plant back in shape," Isaacson.