Work to Begin on South Leg of Toll Road : Transportation: After 20 years of planning and numerous court appearances, the San Joaquin Hills Transportation Corridor Agency will break ground today in Laguna Hills.

Bulldozers will start carving the path of the San Joaquin Hills tollway this morning, officials said, about 20 years after the project was proposed to move traffic through South County.

Mike Stockstill, spokesman for the San Joaquin Hills Transportation Corridor Agency, said Wednesday that two bulldozers and other heavy equipment would start work near Greenfield Drive, in the southern portion of the proposed 17.5-mile corridor.

“This thing is not like the start of a big race or the Oklahoma Land Rush,” Stockstill said. “It’s more like a big steam locomotive pulling out of the station. . . . We’re going about it in a methodical way.”

A federal judge on Tuesday allowed work to begin on the north and south ends of the corridor, which stretches from Interstate 5 in San Juan Capistrano to the Corona del Mar Freeway in Newport Beach. At the same time, U.S. District Judge Linda McLaughlin barred tollway construction, at least temporarily, through undeveloped areas around Laguna Canyon between El Toro Road and Newport Coast Drive. Her ruling remains in effect for at least five months, when she may issue a permanent decision.

Work had been scheduled to begin two weeks ago, but McLaughlin ordered it postponed while she considered environmentalists’ arguments that the tollway would cause irreparable harm to the Laguna Canyon ecosystem.

Lloyd Smith, project manager for the tollway contractor, California Corridor Constructors, said about 10 workers would start working on the site around 8 a.m. today.

“We’ll start moving some dirt,” Smith said. More earth-moving equipment and crews will be brought in in a few days, he added. On Wednesday, the company already had surveyors out in the field, measuring the Bonita Creek area in Newport Beach, where a wetlands is planned to replace former wetlands destroyed by tollway construction.

Judy Davis, of Citizens Against the Toll Roads, said she was not aware of any groups that would protest the beginning of construction work today. “As far as we’re concerned, the canyon is saved,” Davis said.

Meanwhile, Joel Reynolds, attorney for the Natural Resources Defense Council, said the group plans to sue Interior Secretary Bruce Babbitt over his decision not to list the California gnatcatcher as an endangered species. That ruling, based on a U.S. Fish and Wildlife Service finding that the ultimate survival of the gnatcatcher is not jeopardized by the toll road’s construction, even though its habitat will be disrupted, was a bitter blow to toll road opponents several months ago.

Reynolds said he didn’t know when he will file the lawsuit, which has the potential for delaying the toll road project for months, if not years.

Times Urban Affairs Writer Jeffrey A. Perlman contributed to this story.