OXFORD — Stay off the dam.
That’s the message newly installed “danger” signs at the Welchville Dam are intended to send to anyone who uses the popular fishing area on Route 26, by the intersection of Route 121.
The dam is in imminent danger of failing, according to Myron Petrosky of MBP Consulting in Portland.
Petrosky said he recommended to town officials about a month ago that they install warning signs at the dam to alert people to the danger and to protect the town in a case of an accident.
“The condition of the dam hasn’t changed in the last month but significantly changed in the last few years,” he said. “I think people can fish and boat at the dam but should be aware of the risk involved.”
The risk is there regardless of whether a dam is failing or is brand new, he cautioned.
In Oxford the risk is multiplied by the fact that it could fail at any time.
“Every dam poses a danger to the public, upstream or downstream, regardless of its condition,” Petrosky said.
Selectmen voted at their Thursday, June 1 board meeting to hire Petrosky to develop specs that will allow the dam replacement project to go out to bid so they will have a sense of the true costs, but Petrosky said he is still awaiting the go-ahead from the town.
“Considering the current condition of the dam, the earlier start of rehab work is better,” he told the Advertiser Democrat. Petrosky first reviewed the Welchville Dam almost five years ago and has seen the deterioration progress.
According to a survey report by Petrosky, the spillway is a rock-filled timber-crib structure about 140-feet long and reportedly 12 feet high, and controls the water level in both Hogan and Whitney ponds. Petrosky said it was in fair to poor condition at the time he first inspected the structure in 2012.
Deficiencies five years ago included deterioration of crib work, partial washout of uplifting of crib boards, missing structural timbers and stone fill, extensive leakage, deeps voids in the masonry abutment walls and other issues, according to the survey.
Petrosky, who just completed the replacement of the Pleasant Lake Dam in Casco, told the board last month that the costs could be about $1.4 million to repair the dam or about $900,000 to build a new dam. A special town meeting would be called once the true costs are known to raise and appropriate the money.
In Casco, with the combined effort of Casco and Otisfield officials plus representation from the Pleasant Lake and Parker Pond Association, it took a little more than two years to rebuilt the dam after the initial condition assessment.
The Pleasant Lake and Parker Pond Association was active in the decisions from the beginning, pushing the dam owners forward to take action. The Association also financially assisted in the project and had a seat at the table with officials from both towns when determining how to go forward.
Although the Welchville Dam is considered a “low-hazard” structure, Petrosky said if the dam fails he expects the water levels of Whitney and Hogan ponds to drop at least five to six feet. The 170-acre Whitney Pond has a maximum depth of 24 feet, while the slightly larger 177-acre Hogan Pond has a depth of 34 feet. Both ponds, which are located off Route 26, have year-round and summer residences, plus popular summer campgrounds.
The Whitney and Hogan Pond Association officials are aware of the situation.
Petrosky said earlier this month that a dam failure could also send buried, old toxic materials downstream and pose a threat to recreational users in the river at the time of the failure.
Once Petrosky gets the request from the town to go ahead with the project, he said the process including preparation of design plans and specs, contract documentation, bidding, permitting and funding approval would take eight to 12 months.
Interim Town Manager Becky Lippincott told the board last month that there is limited state or federal money available for the work unless the dam classification is upgraded by the state from low hazard.