The Bureau of Land Management has announced its preferred alternative for the 1,150-mile transmission line, planned to run from Wyoming to Murphy.

The $7 billion proposal by Rocky Mountain Power and Idaho Power Co. to upgrade distribution of electricity would be the largest industrial project in the nation.

In 2009, Ada and Owyhee county officials protested that the line and its high towers came too close to their communities and could limit development and affect residents’ quality of life.

So the communities struck deals with Idaho Power to move the route of the towers away from private land to the Morley Nelson Snake River Birds of Prey National Conservation Area on BLM land south of Kuna.

But the BLM now says the lines aren’t allowed in the Birds of Prey area, and has recommended they follow the original route across private land.

City of Kuna and Ada and Owyhee county officials have asked the Idaho congressional delegation for help. And the recommendation that the route go across mostly private land in Cassia County has residents there ready to fight.

In Cassia County, the alternative routes proposed for public lands went through critical habitat for sage grouse, which is close to being listed as an endangered species.

And under the law that created the Birds of Prey area, any development — including a power line — has to help raptors, said Heather Feeney, a BLM spokeswoman in Boise.

Since the BLM’s analysis couldn’t make that case, it moved the lines out of the conservation area and back onto private lands — even though it knew that recommendation would bring a lot of criticism, Feeney said.

The BLM still could make changes before it finishes its environmental impact statement later this year. But every mile adds $1.5 million to $2.5 million to the utilities’ costs, state officials say. That goes right onto customers’ rates.

The fate of the line remains up in the air.

Siting power facilities can be a bureaucratic tangle in Idaho, and the state has little say in the matter. Counties have the last word on where energy projects go — unless the Federal Energy Regulatory Commission steps in.

And because the BLM has final say over what happens on its land, and because the route crosses both public and private lands, BLM has taken the lead on finding the best route.

The BLM will begin taking public comment on the proposal in the near future, Feeney said.

Rocky Barker: 377-6484