The marshy estuary at the mouth of the Snohomish River has been plugged with sediment, channeled for irrigation and just plain tainted with pollutants from the growing city of Everett.

It took a century of abuse to sully this once prime feeding and forage area for healthy chinook salmon.

But under one proposal, 1,500 acres of it could be repaired within a decade.

That is but one of the hundreds of steps toward salmon recovery being discussed in Tacoma this week as more than 400 scientists, government and tribal leaders, business representatives and environmentalists work through details and begin a public campaign to build support for a massive effort to restore Puget Sound's roughly two dozen troubled runs of chinook.

For five years, this group has been working to make Puget Sound the first region in the nation to build an endangered-species recovery plan from the grassroots level rather than have the federal government dictate what the region must do to save fish.

Meeting in groups, the members have worked watershed by watershed to consider where and how to make needed changes to hatcheries, salmon habitat, water flows and temperatures in a way that could help the region's signature fish rebound.

"Each watershed has unique needs and unique threats," said Jagoda Perich-Anderson, associate director of Shared Strategy, the group coordinating the effort.

In Snohomish, restoration efforts already have helped restore several hundred acres of its troubled estuary. On the Cedar River-Lake Washington watershed, for example, restoration planning has focused on creeks like Bear and Issaquah, which have at times run so dry salmon flop about in the mud, said King County Councilman Larry Phillips.

At this week's conference, community leaders will be discussing key unresolved issues, ranging from how to incorporate new science about how salmon use shoreline areas, to how to ease the conflict between farmers and groups trying to save salmon. And, of course, in a time of record federal deficits and a state budget crisis, leaders are still trying to find ways to pay for it all — a tab that is expected to run $100 million to $200 million a year, said Jim Kramer, who is facilitating the entire effort.

On June 30, the group must present its final ideas to the National Marine Fisheries Service, which will determine whether it will satisfy the requirements of the Endangered Species Act.

Still, the effort, led by William Ruckelshaus, former two-time director of the Environmental Protection Agency under Presidents Nixon and Reagan, faces monumental hurdles: Can a plan pass muster with the federal government? And can the region actually provide what salmon need, biologically, to survive?

The plan ultimately will require new rules, which could lead to changes in the way land is developed, the way bulkheads are used and the way water is drawn from area streams — all at a time when rural landowners in King County alone are already seething from new county restrictions.

"The question is, do we have the political will to pull this off?" Kramer said.

Craig Welch: 206-464-2093 or cwelch@seattletimes.com