In a second breakneck day of undoing the previous board's decisions, the Carroll commissioners axed yesterday the proposed $16 million water treatment plant at Piney Run Reservoir in Sykesville, a project that had pitted county government against the state and many South Carroll residents.

The commissioners voted unanimously to walk away from the plan, even though about $2 million has been spent laying the groundwork for the project. They also voted to delete the plant from the county's water and sewer master plan and add the construction of wells and an expansion of the Freedom water treatment plant at Liberty Reservoir to the document, which the state is reviewing.

"We want those changes sent to the state right away," said Commissioner Julia Walsh Gouge. "We will not mention Piney Run in the plan at all."

Besides scrapping the Piney Run plant, which had been favored by former Commissioners Donald I. Dell and Robin Bartlett Frazier, the board also moved to overhaul the county ethics commission by ousting members appointed by Dell and Frazier and pulled the plug on the former commissioners' plans to auction the former Hampstead Elementary School. These moves occurred a day after the new board fired the old regime's top assistant, tinkered with several appointed committees and abolished Frazier's pet project - all within hours of inauguration.

Killing the Piney Run plant was among the sweeping changes new board members promised throughout the recent campaign. The proposal to tap Piney Run Lake as a water source for South Carroll was unpopular from the time Dell and Frazier voted to build it more than two years ago. Both lost their re-election bids in the September primary and acknowledged that the issue was a factor in the vote.

The state contended the plant would promote sprawl and refused to issue a construction permit. State officials urged the county to pursue other options, such as a series of wells at Springfield Hospital Center and expansion of the Freedom plant.

Residents, fearing a plant at the Piney Run Reservoir might ruin its value as the county's most popular recreation spot, doggedly pursued their cause with the state.

"Hallelujah! Obviously, the people's wishes have been heard," said Rich McIntyre, spokesman for the Maryland Department of the Environment. "MDE looks forward to working with the new board to plan and develop water resources. This issue was much larger than Piney Run, and it showed Carroll County residents are more astute about water issues."

Commissioner Dean L. Minnich said yesterday's action could help the county's strained relationship with state government.

"This step depoliticizes the issue," he said.

The county can do nothing to retrieve the $2 million it has spent on engineering designs for the proposed plant as well as a road and pipeline to the location at the southern end of the lake. While the pipeline, tied into the county's water system, might improve pressure in the area, the county owns a $500,000 road to nowhere and about $1 million worth of plans that will be shelved.

The county had drilled and tested wells at Springfield as a possible water source for South Carroll, the most populous area and one that suffers from seasonal water shortages. But Dell and Frazier repeatedly rejected the wells in favor of Piney Run.

Minnich instructed the public works staff to immediately seek state permits to draw water from the wells.

"You cannot do anything without an appropriations permit, which typically takes a year," said Douglas Myers, county public works director, who urged the commissioners to schedule a meeting with the state as soon as possible.

The county has gathered all the data required for the application, but the state is retesting the wells - all on state-owned property - this week, possibly as a backup water source for the hospital and a $60 million police training center set to open on the campus next fall.

"I would hate to see the county lose those wells to the state," Myers said.

The commissioners also will review the Watershed Protection Agreement, a longstanding document among the metropolitan counties and Baltimore City that safeguards land surrounding the water supply. Carroll officials' refusal to endorse the document created an impasse in negotiations to obtain more water at a cheaper rate from the city's Liberty Reservoir.

The Baltimore Metropolitan Council will meet next month to discuss the agreement. Gouge said she expects the county to sign it then.

"This is the way to go," said Commissioner Perry L. Jones Jr.

A signed agreement could help improve the county's negotiating position with the city, said Gouge, adding that she spoke with Baltimore Mayor Martin O'Malley last week.

"The mayor told me the agreement will make a big difference," she said. "The last time we negotiated, things were negative. I think this time will be better."

Carroll can draw as much as 3 million gallons a day from Liberty Reservoir, water it treats at the Freedom plant and pipes to nearly 7,000 homes and businesses in South Carroll.

An expanded Freedom plant could process up to 6 million gallons a day.