Gear Up for Easier Ways to Marine Base : Event: Officials hope to counter the air show traffic jam with alternative routes, road closures and shuttles.

Local law enforcement and transportation officials are preparing for monumental traffic jams when an expected 1 million spectators converge on this Orange County Marine base for the annual El Toro Air Show, one of the most popular military aviation shows in the world.

According to officials at the California Department of Transportation, the 1994 El Toro Air Show will be the largest free event staged in California this year. California Highway Patrol and Caltrans officials said they expect up to 500,000 vehicles to line the highways and byways leading to El Toro Marine Corps Air Station today and Sunday.

Attendance is expected to swell this year because the Blue Angels, the Navy’s precision-flying acrobatic team, are back after missing last year’s show. This will be the 44th year of the El Toro Air Show, and it is not known if more shows are planned for the future. The base is expected to close by 1997.

“It’s not going to be a pretty sight. People are going to have to leave early and bring along lots of patience if they’re going to the air show this weekend,” said Officer Angel Johnson, CHP spokeswoman in Santa Ana.

Irvine police advise local residents and others who plan to drive on surface streets to check for road closures. Most thoroughfares leading to and from the base will be closed this weekend so that the CHP and Irvine police can manage the expected traffic problems.

Irvine police said Barranca Parkway will be closed between 7 a.m. and 4:30 p.m. from Ada to Alton Parkway in each direction today and Sunday. In addition, Irvine Boulevard from Alton Parkway to Jeffrey Road will be closed in both directions between 2:30 and 6 p.m.

Trabuco Road will be closed from Yale Avenue to Sand Canyon Avenue between 3 and 6 p.m. during the weekend to eastbound traffic. Jeffrey Road will be closed from Walnut Avenue to Trabuco Road to northbound traffic during the same period, Irvine police said.

Caltrans announced that the Sand Canyon Avenue off-ramps from the Santa Ana Freeway will be closed intermittently or for extended periods in order to alleviate traffic congestion.

The Sand Canyon off-ramp from the southbound Santa Ana Freeway will be closed between 3 and 6 p.m. Saturday and Sunday and intermittently at other times as necessary.

The Sand Canyon off-ramp from the northbound Santa Ana Freeway will also be closed intermittently when traffic begins to back up on the street, Caltrans said. The closures will occur without notice, officials added.

However, the Sand Canyon off-ramp from the San Diego Freeway will remain open. Just follow the signs to the base.

The CHP is advising motorists going north on the Santa Ana Freeway to exit at Alton Parkway. Southbound motorists should exit at Jamboree or Jeffrey roads or Culver Drive, Johnson said.

Spectators lucky enough to have VIP parking passes should exit at Jeffrey Road from the San Diego or Santa Ana freeways to Trabuco Road and follow the signs to the VIP parking area. All others will have to compete for parking on the 4,500-acre base. Those who arrive late should be prepared for walks of up to one hour from their car to the airfield.

“Basically, the parking lots will be wherever we can fit a car,” said a Marine corporal answering a constantly ringing phone Friday.

The Orange County Transportation Authority recommends that spectators ride shuttles to the base. Buses will leave every 15 minutes between 8:30 a.m. and noon from the Santa Ana Transit Terminal at 1000 E. Santa Ana Blvd. and the Laguna Hills Transportation Center at Paseo de Valencia and Calle de los Caballeros. The fare is $2 each way.

Getting Around The highway advisory radio station, AM 530, will update traffic conditions for the El Toro Air Show. Air show coordinators suggest the following routes to the base: Road Closures The following roads will be closed today and Sunday during the times indicated. 7 a.m. to 4:30 p.m. Barranca Parkway: Ada to Alton Parkway, both directions. 2:30 to 6 pm. Sand Canyon Avenue: At Burt Road, northbound. Irvine Boulevard: Alton Parkway to Jeffrey Road, both directions. 3 to 6 p.m. Trabuco Road: Yale Avenue to Sand Canyon, eastbound. Jeffrey Road: Walnut Avenue to Trabuco Road, northbound. Santa Ana Freeway: Sand Canyon , north and southbound off-ramps. Santa Ana Freeway: Jeffrey Road, northbound off-ramp. Source: El Toro Marine Corps Air Station