NEWPORT, Maine — For the fourth time in four years, one of the chains that open and close the dam at the southern tip of Sebasticook Lake has broken, except this time the cause is a mystery.
In the past, the chains have failed while someone was opening or closing the heavy gate in the center of the dam — at times posing a significant safety problem. A protective cage was built around the gate last summer and engineers installed two Grade 100 chains that are designed to hold approximately 30,000 pounds each.
Apparently, they weren’t strong enough. On Monday, town officials noticed one of the chains was broken again, except this time the gate hasn’t been used in more than a month.
“We don’t know what caused it this time,” said Town Manager James Ricker.
Compounding the problem, the gate shifted to its left and wedged between the dam on either side. The gate has been straightened and resecured, but the big question is how much damage was done below the waterline. Crews from Cianbro Corp. of Pittsfield, which installed a wall of logs behind the gate to stem the flow of water, will return Tuesday to continue their investigation of the problem. Engineers from Kleinschmidt Associates, also of Pittsfield, have been hired to determine the best fix for the problem.
Ricker said the town has nearly $30,000 set aside for maintenance for the dam, but it may not be enough. He said he couldn’t speculate on how much the repairs will cost until he knows the extent of the problem.
“This will undoubtedly drain both of those accounts,” said Ricker, who said the town might have to borrow money for the repairs.
Last summer, crews installed a system of hydraulic flashboards on the upper edge of the dam, which allow the town to regulate the level of the lake without using the heavy gate. However, they are not adequate for the large-scale flushing that’s necessary in the spring and fall.
Proper operation of the dam gate is essential to the town, particularly the property owners on the lake who contribute about 28 percent of the property taxes in town. The gate is used in the spring to lower the level of the lake and again in September to flush out built-up algae. Keeping the lake at the correct level keeps the shoreline from changing drastically and protects what is widely known as a destination for freshwater bass fishermen.
“That lake is very important to our economy,” said Ricker. “We’re trying to promote it as a destination.”