Sediment Woes For Port Angeles Water Treatment Facility Put Elwha Dam Removal On Hold

Apr 22, 2013

The largest dam removal in history is on hold. Dam removal on the Elwha River has been temporarily halted because massive amounts of sediment released from above the dams have clogged one of the city’s water treatment facilities.

A sediment plume is visible at the mouth of the Elwha River, where it meets the Strait of Juan de Fuca.
Credit Tom Roorda / National Park Service website

One of the two dams on the Elwha has been completely removed. That’s released about 20 percent of the 34 million cubic yards of sediment stored up behind both dams.

But the muck, silt and debris has been clogging the intake system at the Elwha Water Facility. The facility provides drinking water to Port Angeles as well as two nearby fish hatcheries and the nearby paper producer.

The city has been using a back-up system that has been in operation since before dam removal began, but experts say it shouldn’t continue to be used in periods of high sediment levels in the river.

Barb Maynes is a spokeswoman for the Olympic National Park.

“As much as we’re extremely eager to see dam removal complete, right now our primary focus is on making sure that the downstream water users have the water that they need," Maynes says. 

The Park Service has signed a $1.4 million contract to fix the problems at the facility, but for right now, removal of the remaining dam on the river has been put on hold.

The Park Service declined to comment on whether it will take legal action against the company that designed the water treatment facility, but acknowledged that that was a possibility.

The brand new $79 million facility was put in specifically to deal with the large flush of sediment predicted to come during dam removal on the Elwha.

Copyright 2013 KUOW