Drinking Water Must Be Boiled Lake Roosevelt Being Drained Stirs Up Mud, Other Sediments

Residents here are being asked to boil their drinking water as Lake Roosevelt is drained to make room for the largest anticipated spring runoff in years.

The low water also has left most boat launches high and dry, so anglers and boaters have a hard time reaching the water.

On Monday, the reservoir behind Grand Coulee Dam was at its lowest level in 15 years, 82 feet below full pool.

The exercise, which began early this year, has been stirring up mud and other sediments since early April, prompting the state Health Department to require drinking-water advisories for the town of Grand Coulee and the eastern side of Coulee Dam, which use treated lake water.

The problem is disease-carrying microorganisms in the water, which are concentrated when the lake’s level is so low.

How long the conditions last depends on how quickly the lake fills with spring runoff and how quickly the turbidity settles, said Steve Clark, manager of the dam.

“People have been tired of it from the start,” Grand Coulee Mayor Bob Seiler said.

“The worst impact is we require businesses to boil or buy bottled water. It’s a hardship for the hospital, schools, restaurants and bars - those who supply water to the public.”

Several other towns near the massive dam get their water from wells and are not affected.