The Sweetheart Lake Hydroelectric Project is nearing the end of its long federal permitting process. On the last day of May, the Federal Energy Regulatory Commission issued its final environmental impact statement for the 111-foot dam and powerhouse planned for a lake southeast of Juneau.
“Based on our analysis,” the report stated, “we recommend licensing the project as proposed by Juneau Hydro with some staff modifications and additional measures.”
Juneau Hydropower Inc. (JHI), the company backing the project, said in a press release that the release of the EIS allows the company “to begin the process to start construction later this year.”
The environmental impact statement is not the same as a license to build a dam, but it is the most significant part of the licensing process.
JHI envisions a dam at the natural outlet of Lower Sweetheart Lake, whose level would be raised to become a reservoir for the project. A two-mile underground tunnel would convey water from the lake to a powerhouse near sea level at the mouth of Sweetheart Creek.
That powerhouse would produce 19.8 megawatts of electricity — a quarter of Juneau’s 2013 electrical load — from three generators. Overland and undersea cables would connect the powerhouse to the existing power transmission lines that link the city to the Snettisham hydroelectric project. The connection would be made to avoid the avalanche-prone sections of that line.
The federal analysis concluded, “power from the project would help meet a need for power, from a clean and renewable source, in the Juneau area in both the short and long term. … Displacing the operation of non-renewable facilities may avoid some power plant emissions, thus creating an environmental benefit.”
The analysis recommended some minor changes to JHI’s construction and operation plan to minimize the effect of the project on area wildlife. One change of note calls for the dam’s operators to consult with the Alaska Department of Fish and Game to develop a plan that would release water from the dam in pulses.
In Sweetheart Creek, below the dam, this would have the effect of mimicking the natural ebb and surge caused by rainfall. Studies have indicated that pulsed flows may improve salmon survival rates.
Sweetheart Lake is currently stocked with sockeye salmon (fish cannot return to the lake due to waterfalls below the lake’s exit) and JHI’s salmon plan calls for the release of at least 21,000 smolt into Sweetheart Creek annually.
JHI would also be required to implement a bear-management plan to reduce the effects of construction on the animals that forage in the creek, and it would be required to grant public access to the dock and boat ramp constructed at the dam site.
Power from the project is intended to go to Kensington Gold Mine north of Juneau. Previous studies have indicated there is a need for about 10 megawatts of electricity at the mine, which currently operates on diesel generators.
JHI intends for the remaining project electricity to power a “district heating system” in downtown Juneau that would displace oil-fired boilers. Instead, those boilers would be connected to hot water piping from a central, hydroelectric-powered heating plant.
Alaska Electric Light and Power, while not formally opposing the project, has raised questions about JHI’s intentions and ability to accomplish its stated goals.
In a letter dated May 25, AEL&P chairman Dennis Vermillion pointed out that JHI’s efforts to license a high-voltage power line between Juneau and Kensington Gold Mine have been put on hold until JHI’s subsidiary, Lynn Canal Transmission, reveals its financial documents.
“The need for power is a significant consideration in conducting analyses regarding a proposed project and deciding whether to grant a license,” Vermillion wrote.