In a small creek off the York River, the largest oyster aquaculture project in the Bay is under way. But unlike other commercial-scale oyster-rearing projects, its oysters are destined for the Chesapeake — not the dinner table.

The Chesapeake Bay Foundation, which proposed the tenfold oyster increase goal included in the Bay Program’s Chesapeake 2000 Agreement, is planning to rear 1 million disease-tolerant oysters annually to stock restored oyster reefs.

Frankly, I think this is the best chance we have of restoring Virginia’s oyster population,” said Tommy Leggett, a waterman and a former member of the Virginia Marine Resources Commission, who is overseeing the project. “I think we stand to see some phenomenal increases.”

Oysters are one of the Bay’s most important resources and historically supported a major fishery. Their reefs, piled many feet high, provide habitat for fish and other species while the oysters filter sediment and algae from the passing water. But their numbers have been devastated by disease, water pollution and overharvesting.

Rebuilding the oyster population — and its filtering capacity — is seen as a critical part of Bay restoration efforts. Many efforts are under way to build new oyster reefs, but coming up with enough oysters to stock the reefs can be a problem.

In the past few years, oysters have come from “buy back” programs that purchase oysters harvested in other areas from watermen, as well as from oyster gardeners who raise the creatures, usually in bags that hang off a dock.

Those efforts have shown signs of success, with oysters transplanted to the new reefs sometimes producing large “spat sets” — young oysters that successfully settle on the reef. But the number of oysters available from those programs is limited to a few hundred thousand per year. The CBF’s intent is to dramatically ratchet that number up.

The group invested about $50,000 to lease three acres of oyster ground, purchase aquaculture equipment and buy tiny oysters produced at a nearby hatchery. The project also requires two full-time employees, Leggett and another biologist, Amy McDonald.

The hatchery-spawned oysters were taken from the Lynnhaven River, where oysters have shown some ability to withstand diseases. The hope is they will pass that trait on to their offspring.

Still, to allow for some disease mortality, the project was starting with 1.5 million oysters, in anticipation that up to a third would die. In fact, Leggett said, nearly half of the initial 48,000 oysters put in the water died after a “phenomenal hit” of the disease, MSX.

Surviving oysters will be placed on reefs next summer in time to spawn — hopefully producing millions of offspring. “It’s not the million oysters a year that is important,” said Rob Brumbaugh, a CBF fisheries scientist. “It’s the offspring they produce.” He said about 300,000 oysters from the first year’s production will go to a sanctuary on the Rappahannock River where Virginia’s Oyster Heritage Program — a partnership between state agencies, business groups and nonprofit organizations including the CBF — has begun building eight oyster reefs. The other 700,000 oysters will go to other restoration sites.

While other hatchery operations place small “seed” oysters in the Bay, those tiny oysters are highly vulnerable to predation.

At the CBF’s York River site, the oysters are placed on plastic trays which are enclosed by screens to protect them from predators, allowing most of the oysters to become adults — something that would never happen in the wild.

Full-size aquaculture oysters are worth about 25 cents apiece on the wholesale market, so the actual economic value of the million oysters being placed in the wild is about $250,000, Brumbaugh said.

Besides benefiting the oyster restoration effort, Leggett and Brumbaugh said they hope the project draws the attention of watermen who may be interested in turning their interest from open-water harvests to aquaculture — something they say would benefit both the Bay and watermen.

“This would be a way for people to continue being on the water, but doing something different,” Leggett said. “Being a waterman, I would love to see more and more people doing this. It would put food on the table, it would put oysters in the water to purify the water and it would keep a culture going.”

Relative to the Bay’s entire oyster population, which scientists say numbers in the billions, a million oysters is not a lot. But it could be an important jump-start to a restoration project, said Steve Jordan, director of the state-federal Cooperative Oxford Laboratory in Maryland.

“Compared with the total oyster population in the Bay, it’s a pretty small number,” he said. “But for a local area, that is a substantial number. A million moderately large oysters per acre is a pretty dense population. I hope they succeed in that.”