By Arwyn Rice
Peninsula Daily News
Want more top stories? Sign up here for daily or weekly newsletters with our top news.
Sediment pouring out of the Elwha River after dam-removal work is causing a number of changes, said Anne Shaffer of the Coastal Watershed Institute, which organized the Friday field day.
“Those include more complex freshwater habitat, additional estuary habitat and sandier beaches,” Shaffer said.
“With the additional sediment, the habitat in the estuary and along the shoreline is transitioning from a hostile, cobbled environment for juvenile fish to one that is soft with sand and much more beneficial for fish migration and forage fish [food for other creatures] spawning,” she added.
The survey was part of the Nearshore Field Workshop, a day for members of the public to explore the changes in the estuary and the area around the Elwha River mouth, as well as in Freshwater Bay, where the river empties its water.
Changes have been made by the release of sediment from dam removal, which is part of the $325 million Elwha River Restoration Project.
Another goal of the outing was to talk with community members about how to protect the nearshore environment.
The workshop was sponsored by the Coastal Watershed Institute, the state Department of Fish and Wildlife, the clothing company Patagonia and the federal Environmental Protection Agency.
On Friday, four areas of the Elwha estuary were seined with nets by a group of fish biologists, college professors and students and volunteers. Two areas were well-established, and two were newly formed.
One of the new ponds, which was formed by new sediment deposits in an area that was part of the river just a few years ago, had a large number of young fish: 84 chinook and 60 coho.
That was a big change from the last time the pond was surveyed in May, when it contained few fish, Shaffer said.
In one of the established ponds, which has been seined for about five years, the number of fish found in the nets was about the same as in the past — 33 chinook, seven coho, 30 sticklebacks, 30 prickly sculpin and four red-sided shiners, Shaffer said.
Changes were slight in the other two ponds.
Most of the young fish found in the newer pond are likely from the May 31-June 1 release of 810,000 baby salmon from the state Fish and Wildlife fish-rearing channel about 3.5 miles from the mouth of the river, Shaffer said.
But, she added, a few were wild fish.
Shaffer said a new resident — a red-sided shiner, a type of minnow not seen before in the Elwha estuary — was found only after the dams were removed and the Elwha River freed.
“The fish numbers overall, in general, are staying the same, but the numbers of each species seem to be fluctuating,” Shaffer said.
“We're smack in the middle of a restoration event,” Shaffer said. “It's interesting to see the changes that are happening right now, but the real story is yet to come when the restoration event associated with the sediment has settled.
“Right now, we're just looking at the equivalent of a construction zone.”
Shaffer said the freshwater habitat is becoming more diverse and that the shoreline habitat is improving dramatically.
The estuary ponds are connected to the river at high tide by several small channels that the river has kept open even as increasing amounts of sediment are deposited in the lower river.
That gives the young fish a place to hide before moving out into the Strait of Juan de Fuca, Shaffer said.
On Friday, scientists were on hand to answer questions from about 20 workshop participants, which included people from age 2 to 80.
The workshop was led by Shaffer, Fish and Wildlife biologist Chris Byrnes, state Department of Natural Resources geologist Dave Parks, University of Washington professor Tom Quinn and Nicole Harris, a recent Western Washington University graduate.
The survey didn't mean much without the five years of surveys made before the dams were removed, Quinn said.
“It's rare to have data from before big events,” he said.
Quinn said that usually, events that cause major changes to the environment, such as restoration projects, don't have data of the fish, wildlife and habitat that existed before they happened, so studies after the fact can be somewhat pointless.
“They [the Coastal Watershed Institute] had the foresight to sample up to five years before the dam removal,” he said.
He said that in addition to having the pre-removal data, information from Salt Creek and Dungeness Spit also is used for comparison.
On Friday, the river's mouth was split.
The larger mouth flowed west, between the beach — which has been built from sediment over the past year — and similarly built sandbars farther from land.
The smaller mouth headed almost directly into the Strait.
Parks led a tour of the beach areas along Freshwater Bay and described the changes to the bay, pointing out the difference between the large cobbles that once dominated the landscape and the sand that is creating new sandbars, beaches and changing the mouth into a more fish-friendly environment.
Sediment was released from the former Lake Aldwell, which was behind Elwha Dam, built in 1912 and removed in 2012, and from Lake Mills, behind Glines Canyon Dam built in 1927 that has been knocked down to 60 feet from its original 210 feet.
Park hydrologist Andy Ritchie said in May that about 20 percent of the estimated 34 million cubic yards of sediment that had built up behind both dams while they were standing had flowed down the river so far.
Shaffer pointed out that the sand grains along the beaches are the perfect size for the breeding grounds of small forage fish, such as surf smelt and sand lance, that are food for salmon, whales and birds.
Reporter Arwyn Rice can be reached at 360-452-2345, ext. 5070, or at email@example.com.