Construction at the New York Power Authority’s Crescent hydroelectric plant will include raising one of the dam’s earthen abutments to make sure it can withstand future flooding on the Mohawk River, according to federal regulators.
NYPA last week announced plans to close the plant’s public fishing access site, for the second time this year, to make way for repairs.
Public access was closed there from December 2012 to mid-July for repairs to an underwater cable damaged during tropical storms Irene and Lee in 2011.
Crescent is one of two hydroelectric plants on the Mohawk River that sustained damage in the storms.
An earthen embankment at the Vischer Ferry plant, located upstream from Crescent in Niskayuna near Lock E-7, sustained damage during the tropical storms, leading to an emergency declaration and temporary fortification work to shore it up. Those repairs are temporary and plans are being drawn up for more repairs there, the Power Authority said in June.
At the Crescent plant, just upstream from Lock 6 on the Canal Corp.’s flight of locks that get boats around the Cohoes Falls, roughly 200 feet of shoreline has been eroding continuously since initial damage from Irene and Lee, according to NYPA spokeswoman Maura Balaban.
Placing large stones and vegetation along the shore are among elements of the repairs, Balaban said in an email. “We are also planning minor additional work to reinforce the area where the dam meets the shoreline.”
According to the Federal Energy Regulatory Commission, the New York Power Authority plans to increase the height of an earthen abutment that was overtopped by the river during Tropical Storm Irene.
The abutment will be raised between 1 and 2 feet “to ensure the project is able to safely pass flood flows,” FERC spokeswoman Celeste Miller said in an email.
She said FERC expects the work to take two months and it should be done by the end of the year.
Miller said the dam is “safe in its present condition.”