One morning in late August, at the peak of an unusually hot summer, I joined a group of scientists on the northern coast of Washington State’s Olympic Peninsula to perform a fish census. We trudged over a dike to a pristine beach just west of the mouth of the Elwha River. Chris Byrnes, a state biologist, and Sheri Washington, an intern with the nonprofit Coastal Watershed Institute (C.W.I.), rowed a small skiff into a shallow pond. Byrnes manned the oars while Washington let out the seine, a net embroidered with buoys along its top edge and lead weights along its bottom, which unfurled into the water like layers of meringue. Once the seine was in place, forming an underwater screen, four of us waded in bellybutton-deep, grabbed hold of its ends, and dragged it toward the shore. (At this point, another intern discovered a pinhole leak in her waders, “somewhere north of the crotch.”)

Near the edge of the pond, still half-submerged, we crowded around the seine and used our fingers to comb the catch. Byrnes grabbed a little fish with a spotted fin and dropped it into a clear, ruler-lined box of water. “Oncorhynchus mykiss,” he said. “Steelhead, seventy, no clip, no tag.” (Translation: seventy millimetres in length, no hatchery marking.) He let it swim away and resumed the inventory. From dry land, Anne Shaffer, the C.W.I.’s executive director, took notes as Byrnes continued to holler. Some of the fish he measured twice—once from snout to tail end, and once from snout to tail fork. “Ten sticklebacks under thirty!” “Coho, one-thirty, one-eighteen, no mark, no tag!” “Chinook, one-sixteen, one-oh-two, no clip, no blip!” (This was a particularly good find, since the leopard-spotted Chinook salmon is classified as threatened under the Endangered Species Act.) A few other reports went unrecorded. “We’ve got tons of snails,” Washington said, ten minutes into the census. Later, a biologist named Tara McBride said, “The fish won’t stay still enough to be measured, little fucker!”

Shaffer and her colleagues have sampled the Elwha’s nearshore region, where the river meets the ocean, once or twice a month since 2006. August, of course, is an ideal time; when you go in January, McBride said, “your fingers freeze, so you just put ’em under your armpits.” The work of the C.W.I. now seems particularly vital, because, for the first time in several generations, the forty-five-mile-long Elwha is a living river, end to end. Between 2011 and 2014, two large, century-old hydroelectric dams were demolished as part of a federal recovery effort. Spurred by decades of litigation, the Elwha restoration is the largest dam-removal and river-rehabilitation project in U.S. history. The smaller of the dams was illegal from the start, built in violation of the treaty rights of the Lower Elwha Klallam Tribe and a state law mandating passage for anadromous fish—species, like salmon and steelhead trout, that return from the ocean and migrate upstream to spawn. Their life cycle is sacred to the tribe and difficult not to anthropomorphize. Hatched in freshwater streams, the salmon swim dozens of miles toward the sea, where they spend their adulthood. Then, when nature calls, they swim all the way back, their skin, accustomed to saltwater, peeling away as they search for their pebbly natal streams. There they mate and die, giving life to bears, birds, and trees.

Scientists with the nonprofit Coastal Watershed Institute (C.W.I.) have been counting and measuring the fish near the mouth of the Elwha River since 2006. Photograph Courtesy E. Tammy Kim Photograph Courtesy E. Tammy Kim

Until recently, the Elwha’s nearshore was an ankle-twisting pile of cantaloupe-size rocks, with occasional swampy pools and thin bunches of sea grass. Now, with the river free to push millions of tons of sand, soil, and woody debris downstream, it has grown by some eighty-five acres. Shaffer has spotted a range of new species in the estuary’s ponds, such as bull trout, redside shiner, and slender eulachon. There are new human visitors, too. “The changes to the beach have changed the way the community interacts,” LaTrisha Suggs, the assistant director of river restoration for the Elwha Tribe, told me. “Back when there were just cobbles, you only had hearty people out there, but now you have people going out to the beach every weekend.”

The change is most visible at Beach Lake, a twenty-six-acre property that borders the Elwha reservation. For years, the dams starved the area of sediment, so homeowners armored the shoreline with concrete, riprap, and rows of boulders to prevent erosion. The C.W.I. recently purchased the land from a private owner, and in August removed some three thousand cubic yards of rock. Shaffer’s team expected modest resedimentation, but the transformation was far more rapid and dramatic than they’d thought possible. Within a few days, the beach had widened by many feet and was edged by soft, fine-grain sand. After several weeks, there were signs of species returning to the brackish waters—sand lance (a tiny prey fish), crabs, flounder, and squid. Once the restoration of the Beach Lake property is complete, it will be deeded to the tribe and opened to the public.

It’s a rare happy story in an age of environmental calamity. But, even with the Elwha dams out of the way, threats of every variety confront the Olympic Peninsula. Shaffer rattled off the ones that worried her most—fish from commercial hatcheries crowding out their wild cousins, the breeding of non-native Atlantic salmon in migratory streams, huge oyster and geoduck farms occupying precious shoreline, and, as on Beach Lake, barriers erected by city planners and wealthy homeowners. (And now, perhaps, President-elect Donald Trump’s nomination of the Montana congressman Ryan Zinke, an advocate of logging and drilling on federal lands, to lead the Department of the Interior.) Cleaning up a river, Shaffer observed, means accounting for factors far afield of its immediate path. It doesn’t help that the nearshore is miles away from the former dams and outside the confines of the park, giving it a somewhat marginal status. The river mouth and surrounding delta were excluded from the congressional budget for dam removal and river restoration; thus, the C.W.I. and the Elwha Tribe have relied on a patchwork of research grants to fund their decade-long studies of the area.

The day after my expedition with the C.W.I., I went seining on the east side of the Elwha nearshore with four natural-resources workers from the tribe. Conditions were perfect, if a little warm for juvenile fish. We seined under blue skies, taking in the squawking seabirds and miles of wild tidal beach. The team leader, a veteran biologist named Rebecca Paradis, has made her career on this stretch of land. She brought along Gabe Youngman, a tribal member who grew up fishing the river and got his start in conservation as Paradis’s middle-school intern. In the algae-filled ponds of the New Delta East—land created by the undammed Elwha—we netted hundreds of knuckle-size sculpins, sticklebacks, snails, and baby flounder, along with lots of perfectly round beaver poop. We captured almost no salmon or trout, but the team seemed unconcerned.

Afterward, as the rest of the crew loaded the boat and equipment onto the trailer, Paradis gave me a tour of the expanding river mouth. “We knew we would get some sedimentation in the estuary, but we were thinking centimetres,” she told me. “We got feet.” The land was beginning to resemble its old self. More than a century ago, before the two dams went up, tribal members lived in seaside homes and fished not only for salmon but also for crustaceans and shellfish. Now, with the sand replenished, the Elwha people were again crabbing in their historic territory. Paradis and I paused to wash the mud off our waders, looking north over the Strait of Juan de Fuca, which separates Washington from British Columbia. During a lull in conversation, I heard a drumbeat and singing in the distance. A few hundred yards away, we spotted a small crowd. The tribe was holding its annual First Salmon Ceremony, a ritual in which a fish is flayed and carried out to sea on a bed of pine needles. I’d attended this ceremony two years earlier, just after the last bits of dam were removed.

Since 2012, when tribal and state leaders instituted a five-year fishing moratorium on the Elwha, the ceremonial salmon has been brought in from elsewhere. Though the spawn counts are improving, the moratorium will likely be extended by at least another year. Scientists with the tribe counted only twelve hundred Chinook this autumn, compared with four thousand in each of the past three years. But Keith Denton, a consultant to the tribe, said that this wasn’t so surprising. The Chinook that returned this year were born in 2012, when the river “was running chocolate milk,” he said. During the demolition, few juveniles survived; there was nothing to do but wait for the water to clean itself. Two years on, the Elwha runs magnificently clear, a promising forecast for the fall runs of 2020. In the meantime, the tribe and the C.W.I. will proceed with their work. “Massive rip in the net this morning,” Shaffer texted me recently. “Merry Xmas, my ass.”