WASHINGTON - The government declared two swaths of the country critical to the nation's electricity grid yesterday, pushing for construction of major power lines in Southern California and along the East Coast.

The Energy Department proposed two "national interest electric transmission corridors," the first of their kind under a 2005 law that could overcome local objections in order to relieve bottlenecks in the electricity grid.

The current grid "is aging and stressed. Simply put, it is no longer adequate to meet the demands of the 21st century," Energy Secretary Samuel Bodman said. He also said the government would take a more aggressive role in energy projects opposed by local groups.

"The parochial interests that shaped energy policy in the 20th century will no longer work," he said.

The proposed Southwest corridor would be composed of seven counties in Southern California, three in Arizona, and one in Nevada.

The mid-Atlantic corridor would run north from Virginia and Washington, and include most of Maryland, all of New Jersey and Delaware, and large sections of New York, Ohio, Pennsylvania and West Virginia.

The proposed corridors were announced a day after some House Democrats had criticized the 2005 law's possible effects.

The law gave the federal government greater say on where high-priority transmission lines should be built. If states and regional groups fail to build such lines, the government could order them built.

Concerns about congestion in the electrical grid were heightened after a major blackout in 2003 that swept from Ohio to Canada and New York City.

Still, local representatives fighting proposed towers in their communities were incensed by the announcement.

"The federal government is continuing to try to usurp state authority and override the Constitution," said Rep. Maurice Hinchey (D., N.Y.), who is fighting a proposed transmission line through his upstate district.

The corridor designations could help private industry obtain permits from state regulators or to work in conjunction with regional groups to build new lines.

Utilities in New York and other states have long accused state authorities of being reluctant to approve new lines, often because of local opposition.

Authorities will hold public meetings on the corridors in San Diego, Arlington, Va., and New York City.

Once the 60-day comment period ends, the law calls for state regulators to try to strike an agreement on where new lines should be built.

If state authorities do not approve any construction after a year, the Federal Energy Regulatory Commission has the authority to intervene and approve a grid project if the new line is deemed necessary to satisfy national power needs.