Potential federal protection of sage grouse is forcing Idaho Power Co. to rethink locations for a transmission line planned for south of the Wood River Valley—area that is key habitat for the bird.
The proposed line is separate from a backup transmission line being planned from a substation north of Hailey into the Ketchum and Elkhorn substations, but it is part of the Wood River Electrical Plan, drafted in 2007 by Idaho Power and a community advisory committee to improve reliability.
As the Forest Service and BLM introduce conservation measures to prevent the bird from endangered species listing—in advance of Fish and Wildlife Service's decision in 2015—a governor's task force is developing recommendations to manage the bird. As part of the process, habitat has been mapped for priority, or key, habitat and for general habitat.
"It will affect one of the proposed pieces of this overall project," said Brett Dumas, environmental supervisor at Idaho Power. "Sage grouse regulations changed the permitability of that route quite a bit. It's going to limit infrastructure development in those areas."
One affected portion of the electrical plan is a new, third power line from a station near Shoshone to a substation proposed along state Highway 75 near Burmah Road, southeast of Timmerman Hill—on federal land and key sage grouse habitat.
Also affected is a proposed 138 kV transmission line that was envisioned from the new Burmah substation to Moonstone substation, east of Fairfield. That line can't be built without the Burmah substation. Additionally, the route along U.S. Highway 20 to Moonstone is sage grouse habitat.
"Those are probably not going to be viable, given the constraints that sage grouse conservation measures will have," Dumas said.
Another part of the 2007 plan—upgrading the existing line from King substation, just north of Hagerman, to Moonstone substation from a 138 kV transmission line to a 230 kV line—will likely be given higher priority, he said.
"Because of limitations on the third line, that will move forward in priority," he said.
"The risk and the uncertainty of building the new line were too high, so we're choosing the option of rebuilding the existing line," he added. "That gives us nearly as much reliability and capacity as the new line would have."
That line crosses federal land and sage grouse habitat, and a moratorium on new construction in sage grouse habitat is in place, said company spokesperson Lynette Berriochoa. But rebuilding a line does not fall under the moratorium.
"We have already permitted the reconstruction of that line at 138 kV," she said.
The company is seeking approval from the BLM for more capability in the future.
"We would like to ... have approval to build it at 230 kV but energize it for 138," she said. "We hope to know that very soon."
Rebuilding the King line, if done in conjunction with the northern valley's second transmission line project, would meet the reliability and capacity needs of the valley for the next 10 or 20 years, Dumas said.
He said that if the community wants to move forward with a third line south of Timmerman Hill, sage grouse protections could restrict that location to alongside highways.
"The [advisory committee] is not too excited about bringing in the line along Highway 75," he said.
He said the third line idea could be revived and reconsidered once species listing decisions and BLM land-use plans are made.
Dumas said that portion of the project was not scheduled for detailed planning for several years, but it will require new options for consideration if and when Idaho Power and the community decide to pursue it.
"We'll likely reconvene that committee way down the road if we want to do a proposed third line," he said.
Rebecca Meany: rmeany@mtexpress.com
South-north valley transmission line planning continues
Idaho Power representatives are meeting with homeowners and homeowner associations along the proposed route of a second transmission line between Hailey and Ketchum/Sun Valley, said company spokesperson Lynette Berriochoa. The north valley has one 138,000-volt transmission line bringing in power. Installing a second line would provide a backup if one fails due to weather or technical problems. Officials plan to hold open houses this summer to continue to gather feedback and answer questions about the second line. "We'll keep information out there," Berriochoa said.