I saw this article today on the LA Times blog and on the NC Times website:

State tries to free up car-pool lanes; California's hybrid policy triggers federal requirement to keep lanes open

By: DAVE DOWNEY - Staff Writer

Under pressure from the federal government, California transportation officials said Tuesday they will devise a strategy by the end of August to free up clogged car-pool lanes.

Measures could include adjusting the hours that the car-pool requirement is in effect, stepping up California Highway Patrol enforcement, allowing continuous access into the lanes and limiting access to hybrids on congested freeways, said Tamie McGowen, a Caltrans spokeswoman in Sacramento.

On Friday, the Federal Highway Administration told the California Department of Transportation the state is out of compliance with federal law because it has allowed lanes to become congested, state officials said.

Car-pool lanes were intended to give commuters who double up a smooth ride. The federal agency considers lanes to be congested -- and out of compliance -- when minimum speeds drop below 45 mph more than 10 percent of the time.

Formerly, California did not have to live up to that standard. That changed when the state began letting solo drivers of gas-electric hybrids into the lanes in late 2005, McGowen said, in a phone interview. She said the Federal Transportation Act is invoked when hybrids are involved.

"The good news is that people are using the car-pool lanes," McGowen said.

California has issued 85,000 car-pool-lane stickers to owners of Honda Insights and Civics, and Toyota Priuses, which get 45 miles per gallon or more.

Despite the surge of interest in hybrids, they are not to blame for congestion in car-pool lanes, McGowen said.

"The increasing population is a huge factor in this," she said. "And the bottom line is that the number of vehicle miles traveled is increasing faster than the population."

In Los Angeles and Orange counties, congestion in car-pool lanes has become a serious problem. Officials say it is rare in San Diego and Riverside counties.

John Standiford, a spokesman for the Riverside County Transportation Commission, said car-pool traffic often backs up on Highway 91 in Corona, but elsewhere ride sharers enjoy free flow.

Garry Bonelli, a spokesman for the San Diego Association of Governments, said congestion has yet to surface on the eight miles of car-pool lanes on Interstate 15, which double as toll lanes for paying solo commuters.

Bonelli said the transportation agency is hopeful that it will be able to keep those lanes clear through strategic pricing of tolls. Charges range from 50 cents in light traffic to $8 in gridlock.