(Host) The falls of Otter Creek in Vergennes look quite different this summer.
Water has been diverted from one of the river’s three spillways so that the headworks of the hydroelectric plant can be replaced.
Green Mountain Power has put temporary dams in place to allow heavy equipment to pass under the Route 22A bridge to remove the penstocks. Those are the pipes that allow water to flow into the electric plant. The penstocks will be replaced in the coming months.
Green Mountain Power’s John Voyer says the dam is about 100 years old and the time had come for a replacement of the headworks, which divert water to the turbines.
(Voyer) "We’ve been monitoring it for quite some time and we had some engineers take a look at it and make some recommendations. We figured that it’s a great economic resource. It’s one of our lowest cost power and so we felt that it was important to maintain it and to take it out of service and to make the repairs."
(Host) GMP had hoped to complete the project last summer, but heavy rains made the installation of temporary dams impossible.
Those dams have several safety features to protect workers below them. And Voyer says the work is being done carefully to prevent any damage to historic buildings on islands above the falls.
(Voyer) "We have all kinds of vibration monitors out there to make sure that we’re keeping any vibration levels very low. We had engineers review the activity that we’re doing, which involves some blasting and some hoe ram work, to ensure that any vibrations produced would be a non-issue."
(Host) In the meantime, the northern spillway of the falls is still creating power. The combined Vergennes hydro-plants generate enough power for over 1,200 homes, more than the number of houses in the little city.
Green Mountain Power says the dam is an important source of low-cost, clean energy. And it’s central to the company’s history. GMP traces its roots back to Vergennes Hydro.
The $3 million project is likely to be completed in January.