CASCO — Selectpersons from Casco and Otisfield have agreed to ask permission from the Maine Department of Environmental Protection to temporarily lower the minimum water level at the Pleasant Lake dam to study how to repair it.

It’s the first step to determine the best and most financially feasible way to prevent the dam from totally collapsing.

“Is what we want to repair or replace it, and how much will it cost? We want answers at the end of the day,” Casco Selectboard Chairman Grant Plummer told board members and Peter Barber, president of the Pleasant Lake Association, at Tuesday night’s meeting in the Casco Community Hall.

Maine Emergency Management Agency officials inspected the dam Aug. 15 and reported significant leakage and structure deterioration. Local officials say it has been losing as much as 1,000 gallons of water per minute in at least three places.

A 1978 agreement with the Department of Environmental Protection mandates that the water level at the dam remain at least 5 inches above the spill-gate top, but breaches in the structure have caused that number to drop to 3.6 inches, which has brought the level of the lake down significantly.

“It’s breaching everywhere. There’s all sorts of issues with the existing dam,” Otisfield Selectman Rick Micklon said.

The dam is on Mill Brook, behind the Hancock Lumber office on Route 121. It regulates the water level of the 3.8-mile-long lake, which lies in Casco and Otisfield. There are numerous homes and cottages around the lake, as well as the Seeds of Peace International Camp on the western shore and Camp Arcadia for Girls on the eastern shore, both in Otisfield.

The dam has been jointly owned, operated and maintained by Casco and Otisfield since 1994. It previously was owned by Hancock Lumber Co.

According to the Maine Dams Inventory, the 110-foot-long, 12-foot-high dam was built in 1850, repaired in 1980 and has low-hazard classification, meaning there is nothing significant downstream that would be affected by a dam breach.

Myron Petrovsky, principal of MBP Consulting in Portland, who authored a report on the dam’s condition for the two boards, said the overall condition of the dam is poor and almost every component of the dam is leaking.

“The dam appeared stable at the time of the inspection and no signs of imminent failure of the structure were observed,” Petrovsky’s report said. “However, the existing numerous dam deficiencies, such as severe deterioration, excessive seepage and limited hydraulic capacity, may require at some point in the future to perform major repairs to improve operation and reduce a risk of its failure.”

Casco Town Manager Dave Morton said the water spillage is significant and attempts to keep the water from undermining the structure have been difficult.

“We can’t let enough water out of the dam to stop water from going over the top during significant storm events,” he said.

Normally, four 8-foot oak and pine planks are used to manage the level of the water going over the dam and, subsequently, the level of the lake water. The state allows the boards to be taken out between April 15 and Oct. 15 to regulate the water level, depending on whether there is significant rain.

To address the situation, the board looked at several short-term measures recommended in the Petrovsky report that could cost $10,000 to $12,000, including conducting a survey before repairs.

But the boards differed on how to immediately pay the estimated $6,000 survey cost, which would be shared by the towns.

Otisfield Board of Selectmen Chairman Hal Ferguson said his board would like to move slowly, first dealing with short-term, low-cost resolutions because the Petrovsky report indicates there is no “imminent danger” of the dam collapsing.

He and fellow board members Len Adler and Micklon agreed that any money, even $3,000 from the contingency fund, must go before voters for approval.

While both boards have a contingency fund, which generally covers unanticipated emergencies during a budget year, Otisfield selectmen are not authorized to use the money without voter approval. In Casco, Morton said the use of the contingency fund is “at the discretion” of the board.

Barber offered, and the boards agreed, to come up with bids from several companies for the survey work. He also offered to inform the 300-plus membership of the association about the problem and work to resolve it.

The boards agreed they should come up with a specific money figure, which could be $10,000 to $12,000 for the survey and gathering hydrological information, and bring it before town meetings next June for approval.

All agreed that the public should be educated on the problem and resolutions, including costs, before then.

A subcommittee will meet next month to discuss the ongoing issues. Debris around the dam will be removed.

ldixon@sunjournal.com