Dam Repairs Are Progressing Slowly

Effingham – October 27, 2009 — If the weather holds and the level of the lake is low, some of the work required in advance of repairing the Ossipee Lake Dam complex will take place in November, according to Kent Finemore, assistant chief engineer of the DES Dam Bureau in Concord.

Speaking with Ossipee Lake Alliance by phone, Finemore said the Town of Effingham has been advised by notice that drilling for geotechnical borings will be made in wetlands on the northern side of the complex in compliance with the State Code of Administrative Rules Section Env-Wt 303.05(n). Data from the borings is needed to complete the final design plans during the winter.

The plan is to replace the deteriorating concrete dam at the northern outlet channel, which is known as the Berry Bay Dam, and increase discharge capacity per dam safety rules. The intended design will include an automated hydraulic gate system so that discharge capacity can be increased remotely during times of potential flooding.

Depending upon the final price tag and the availability of construction funds, the project may occur in two phases. The first would be the replacement of the existing concrete dam, and the second would be the installation of the automated gates. If it does become a two-phase project, DES will use stop-logs, similar to the system that exists now, to control impoundment levels until the automated gates are installed.

The second dam at the complex, which is on the southern outlet channel and is known as the Head Works Dam, does not require work and will remain in place and continue to be operated manually.

Finemore said he hopes to be in the final phases of design by early next summer, after which the Bureau must continue to pursue state and federal permitting for the project.

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