Years of work to restore Johnson Creek, a 26-mile stream that winds from the foothills of Mount Hood near Boring to the Willamette River near the Sellwood Bridge, are paying off.

In a breakthrough last month, three dead coho salmon were discovered 15 miles upstream -- the farthest in memory, said Matt Clark, executive director of the

, a nonprofit that works to protect the creek.

"This is another sign that the creek is responding to decades of work," said Laura Guderyahn,

watershed restoration coordinator. "We've done numerous surveys and seen an increase in birds and reptiles. What all this shows is that the creek is becoming healthier for wildlife."

Wild salmon used to be found throughout the creek but vanished in many areas because it was unable to sustain them, said Robin Jenkinson, the Watershed Council's restoration coordinator.

But in the past 20 years, 300 reclamation projects have been launched, according to a Watershed Council database. The next one will be a volunteer effort Monday to plant 520 trees and shrubs along about 450 feet of creek banks in Milwaukie's Mill Park.

"The trees will help keep the creek cool in the summer," Jenkinson said. "If the water gets too hot, the fish die."

Johnson Creek is one of the metro area's few streams that can sustain wild populations of steelhead, coho and chinook, Jenkinson said. All three are threatened species, she said, making it vital that Johnson Creek be reclaimed.

"Over the past 100 years, the creek has changed," she said. "Some of the big changes were logging and farming. When pioneers moved to the area, they created slash dams so they could float logs downstream. In some spots, you can still see eye hooks that were drilled into the bedrock."

The dams, though, killed fish by keeping them from their spawning grounds. Pollutants and chemical spills over the years also killed bugs the fish feed on, she said.

In the 1930s, the city of Portland launched a massive project to dig a channel in Johnson Creek, lining the banks with rocks to lessen flooding. That created rushing water that flushed young fish right out, Jenkinson said.

Since then, the city has worked to right that wrong, letting the creek flood in areas. "They've been able to create natural flood plains, Jenkinson said. "All the jurisdictions that have a piece of the creek work together and meet once a month to coordinate things."

Doug Drake, lower Willamette River basin coordinator for the

, agreed that the creek is on the mend.

"It took us 100 years to put a big urban footprint on Johnson Creek," he said. "It's going to take that kind of time scale to bring it back. But it is getting better. The county and cities have spent money on bank restoration, which helps the creek, and other projects to make the creek more natural."

The dead fish found in early December were identified as wild coho by the

after a chain of events. A woman walking along the Springwater Corridor spotted a dead salmon in the creek and mentioned it to a friend, an employee of the

The friend recognized the significance and told her to contact Gresham officials, who sent out a bioengineering/fish habitat contractor. He spotted two more dead fish, and all three were sent to the state.

Jenkinson said money to improve the creek comes from the Oregon Lottery, the federal government, private foundations, cities, counties and individual donors. In 2006, voters approved a bond issue to allow

to spend nearly $11 million for a pair of parcels flanking Clatsop Butte in outer Southeast Portland to stabilize slopes, filter stormwater, and provide shade and shelter along Johnson Creek.

"In the global world of restoration, what's happening on Johnson Creek is unique," she said, adding that river-reclamation specialists from Russia and Canada have visited Johnson Creek to talk with experts.

"I've presented papers on the creek in Italy and France," she said. "We're still learning about the creek and what it offers. What it shows is how the ecosystem is linked."