AQUASCO, MD. -- Potomac Electric Power Co. opened a $600,000 aquaculture center last week at its Chalk Point Generating Station to spawn rockfish to restock the Chesapeake Bay.

The hatchery has eight tanks that can produce about 100,000 fish a year for release in the Patuxent River, a Chesapeake Bay tributary, said Tom Welle, a utility spokesman.

Populations of rockfish, also called striped bass, have declined in recent years, prompting a 1985 ban on striped bass fishing in Maryland.

Pepco started its fish culture project in 1985 in nearby ponds, Welle said. Rockfish spawned in 11 ponds will continue to augment the hatchery, adding several thousand fish for the rejuvenation program, but the tanks enable company biologists to grow the fish to a larger size, he said.

"It also ensures their survival in captivity until they can be released," Welle said. Biologists started stocking the tanks in June, and once the rockfish are large enough to survive in the wild, they are turned over to the state to be released in the river.

Other utilities have similar programs, but the Chalk Point facility is one of only two on the East Coast using a special pump that adds oxygen to the water, Welle said.

Water from the Patuxent is pumped through the tanks at a rate of 2,000 gallons a minute, said Welle, adding that oxygen helps improve the survival rate in summer when low oxygen levels can endanger aquatic life.

State environmental officials and Gov. William Donald Schaefer attended the Friday dedication ceremony at Pepco's Chalk Point plant.