The West Point Treatment Plant is at half capacity and can’t manage heavy rain.

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King County is dumping raw wastewater including sewage into Puget Sound at the rate of 50 million gallons a day as its damaged West Point Treatment Plant limps at half capacity during heavy rain.

The untreated effluent, about 90 percent stormwater and 10 percent raw sewage, is being dumped from an emergency outfall pipe a few hundred feet offshore in water about 50 feet deep at West Point, said Doug Williams, King County spokesman.

The emergency bypass will continue as long as the plant off Discovery Park in Magnolia can’t manage heavy flows resulting from rain that is more than three times that of a typical February. Rain is expected through the week.

The county is also diverting about 150 million gallons per day of effluent to other treatment plants within the system, depending on their capacity during the wet weather, Williams said.

The West Point plant has been running at half capacity since Feb. 9 after a pump failed, causing some portions of the plant to flood and damage equipment, Williams said.

The wet weather is causing the county to dump effluent it can’t treat with the undercapacity, crippled plant. The county is in violation of its permits as it dumps the untreated sewage, exposing the county to monetary fines. The county has notified regulatory agencies and tribes with treaty fishing rights in the area of the situation.

Work is under way to clean and repair the plant and determine why the pump failed Feb. 9. The plant is operating at about 220 to 250 million gallons of capacity per day because of the damage, or about half its usual performance.

The plant bypassed 260 million gallons of untreated flows to Puget Sound beginning early in the morning on Thursday, Feb. 9, and stopped about 19 hours later in the evening the same day, Williams said.

The additional bypassing of untreated flows began again at about 2 a.m. Wednesday because of the wet weather, and is continuing.

A wet air mass stretching to Hawaii has Seattle in for even more rain, which could break the February rainfall record.