OLYMPIC NATIONAL PARK — Another section of Glines Canyon Dam has disappeared in a shower of concrete and silt, reducing the dam to a low wall covered in rubble.

The blast at 5:36 p.m. Monday removed a large section of dam on the east side of Glines Canyon, said Olympic National Park spokeswoman Barb Maynes.

A stub of the dam still remains above the waterline on the western side of the river.

That and the dam’s apron, bits of dam under the waterline and a slab of hardened concrete built below the riverbed to anchor the dam are all that remain of the 210-foot arch dam, built in 1927 to provide power for fledgling Port Angeles industry.

The remaining stub of dam is not visible on the Olympic National Park webcam, Maynes said.

The next blast is not yet scheduled.

Engineers with Barnard Construction, the contractor hired to remove the dam, have told the park they hope to finish the dam-removal portion of the project by May, Maynes said.

Maynes said the projected May removal is dependant on weather and the possibility of mechanical breakdowns.

Monday’s blast originally was scheduled for Sunday, but ice and wind delayed the delivery of explosives to the site, she said.

The dam site is not yet passable for salmon, despite the apparent disappearance of a cascade that blocked salmon from getting upstream to the pristine Elwha River Valley in the heart of Olympic National Park.

The slope of the river at the dam site is still too steep, resulting in rapids too fast for salmon to pass.

“They need pools as resting areas,” Maynes said.

Rubble from the dam-removal process built up in the streambed below the dam, which artificially raised the elevation of the riverbed.

Most of the rubble will be removed, she said.

With pools, salmon

Fish biologists told Maynes that once the silt and rubble settle and the pools form, they expect to begin to see salmon attempt to pass through Glines Canyon.

The next salmon run is expected to begin in May.

Removal of the dam is part of the $325 million Elwha River restoration project, designed to open the 70 miles of river to salmon and steelhead.

Engineers estimated that more than 34 million cubic yards of sand, silt, cobble and gravel was trapped behind the dams.

Silt that has been released has formed new beaches around the mouth of the Elwha River.

Glines Canyon Dam once held up to 40,500 acre-feet of water in Lake Mills.

The older Elwha Dam, which was located 8 miles north of Glines Canyon Dam, was removed in 2012.

The two dams, which once provided all of the electrical power needed for Port Angeles, by 2010 only produced 40 percent of the power needed for a single paper mill.

Lake Aldwell, which once spread behind Elwha Dam, is almost fully replanted.

Once dam removal is complete, fish biologists said, they believe Elwha River salmon and steelhead populations could grow to nearly 400,000 returning fish per year.

________

Reporter Arwyn Rice can be reached at 360-452-2345, ext. 5070, or at arwyn.rice@peninsuladailynews.com.