PORT GAMBLE, Kitsap County — As much as 7,000 acres of prime woodlands in North Kitsap County could be protected from development under an agreement announced Wednesday by Pope Resources and the nonprofit Cascade Land Conservancy.

The huge swath of undeveloped forestlands, including two miles of waterfront between Port Gamble and Kingston, had been scheduled for rural residential development, possibly into 20-acre ranchettes. But the Poulsbo-based timber and development company agreed to give conservationists 18 months to assemble the money needed to buy all or part of the land and prevent its development.

The deal could protect thousands of acres of recreational green space in a suburban area with a population of 70,000 residents just 15 miles west of downtown Seattle.

"This deal opens a door, but we still have to find the means to go through," said Michelle Connor, vice president of the Cascade Land Conservancy, a Seattle-based nonprofit with a track record of negotiating creative conservation deals.

Conservation groups will immediately begin looking for money — public or private grants or other funds, she said, amounting to "tens of millions" of dollars. The final price tag will depend upon an appraisal of the property.

Despite the uncertainties, the agreement could turn a new direction in the perennial tension between timber firms and environmentalists over large parcels of logged-out timberlands in the Pacific Northwest. It also points toward a possible future for Port Gamble, the historic mill town still wholly owned by the company that built it 150 years ago.

Port Gamble was founded in 1853 by Andrew Pope and William Talbot, New England entrepreneurs who built a mill there to provide lumber for the California Gold Rush. Enriched by thousands of acres of rich timberland surrounding the mill, the company and town prospered until the 1990s, when the mill was closed by changing economics.

Since then, Pope Resources has been studying what to do with the town and the thousands of acres of surrounding timberlands, most of which has been logged three times over.

Meanwhile, the Pope land has been open to hikers, who have developed trails that weave through the woods from Poulsbo to Hansville.

Two years ago, Pope proposed to turn over much of its land for conservation and recreation in return for allowing them to build and sell some 1,200 new homes near Port Gamble. But that plan was fiercely opposed by the Port Gamble S'Klallam tribe, based across the bay from the milltown.

Negotiations resumed early this year, with the regional Cascade Land Conservancy taking the lead. "It's been six months of hard work," Connor said. "But we've worked with Pope before in Southwest Washington, and we've found them to be conservation-oriented."

Jeromy Sullivan, chairman of the Port Gamble S'Klallam Tribe, said the deal could help ensure protection of valuable shellfish beds in Port Gamble Bay.

"We have an obligation to our ancestors, our elders and our youth to ensure that Port Gamble Bay will be restored and protected for the future."

But advocates still face the daunting task of finding money. Possibilities include the Navy, which could offer up funds as mitigation for the environmental impact of planned expansion of its dock facilities at the Bangor submarine base.

Jon Rose, president of Pope Resources' real-estate subsidiary, said negotiations have been complicated, in part because the purchasers may only be able to buy certain parcels.

Pope Resources has placed about 20,000 acres of Puget Sound woodlands in conservation since 1998, Rose said.

"But this deal would be unique because of the ready access to 70,000 people, the trails and the two miles of undeveloped waterfront," he said. "If this is successful, it opens new possibilities for corporate, community and tribal cooperation."

Connor also expressed hope that preserving the surrounding forestlands would bode well for the future of the town.

"This could define a kind of future for Port Gamble as a town that hearkens to the past and to the future."

Ross Anderson is a freelance journalist and former Seattle Times staff reporter now based in Port Townsend.