SEATTLE – The federal government has given its stamp of approval to a plan that will try to keep Puget Sound’s endangered chinook salmon from going extinct and return their population to healthy numbers.

The plan was developed over five years by Shared Strategy for Puget Sound, a coalition of citizen groups and local, state, tribal and federal representatives. The National Marine Fisheries Service, which approved it Friday, called it the largest and most comprehensive recovery plan prepared under the federal Endangered Species Act.

“It’s been a long, arduous process,” said Joan McBride, deputy mayor of Kirkland. “It started many years ago, and I think this is a day to celebrate.”

The blueprint plan calls for spending $1.2 billion in the next 10 years – a doubling of current efforts – to boost chinook runs by 20 percent.

“The big challenge is implementation,” said Doug Osterman, a King County employee coordinating salmon recovery in the Green and Duwamish rivers and along 90 miles of marine shoreline. “We’re really going to rely on state and federal governments to come through with the funding.”

Over decades, habitat loss, overfishing, competition with hatchery fish, pollution and other forces have combined to dramatically reduce the native chinook runs in Puget Sound.

Among other things, chinook recovery will require tougher land-use restrictions to ease human impacts on the fish and their environment. The plan says recreational and tribal fishermen will be asked to do even more to reduce their harvest of wild chinook, and hatchery management will be rearranged to protect wild fish.

At the state level, Gov. Chris Gregoire’s proposed 2007-09 budget contains $50 million in new money aimed at salmon habitat restoration work.

The groups implementing the plan in 14 regions around the Sound have gone through an exercise to determine which projects are most important. They have selected a set of projects that they hope to complete within the next three years.