Two dams have received approval to boost their energy capacity and fill the gap left when three other Penobscot River dams are demolished or decommissioned over the next two to three years.
The Department of Environmental Protection cleared Black Bear Hydro Partners LLC, the company that owns the Stillwater and Orono dams, to build new powerhouses and turbines at both dams that will more than double their capacity, according to Scott Hall, Black Bear Hydro’s manager of environmental services.
The project still needs to go through the Federal Energy Regulatory Commission’s licensing process, which should be completed by the end of the year, Hall said.
“We hope to start construction on those projects next year,” he said.
The construction will include a new powerhouse at each site, as well as expanded turbine units. The additional turbines will harness the power of water that today just spills over the top of the dams when the river is running high.
Black Bear Hydro estimates the upgrades will boost the energy capacity of the Orono dam from 2.78 to 6.52 megawatts and the Stillwater dam from 1.95 to 4.18 megawatts.
“With these two upgrades, and with all the other improvements that are being made, we believe it will replace all the energy being lost by removal of two other dams,” Hall said.
The two dams slated for removal are the Veazie dam and the Great Works dam in Old Town. The Penobscot River Restoration Trust purchased those dams and another in Howland with plans to put them out of service and allow fish to travel farther up the Penobscot River into the central portions of the state.
The trust plans to dismantle the Great Works dam in the summer of 2012 and the Veazie dam sometime in 2013 or 2014. The Howland dam will be decommissioned and bypassed by a fish lift. A dam in Milford also is scheduled to get a fish lift.
Hall said the construction at the Orono and Stillwater dams would cost around $20 million, with smaller fish passage and energy upgrades at other Black Bear Hydro-owned dams adding to that price tag.
There aren’t any plans to expand energy capacity beyond past levels, but it could be a possibility for the future after projects associated with the river restoration are completed, Hall said.