LAGUNA NIGUEL, Calif. -- Orange County sheriff's deputies will be out in force Saturday in an attempt to clamp down on public drunkenness and rowdy behavior that has come to mark the annual "mooning" of trains along a stretch of tracks in Laguna Niguel.

Last year's 29th annual drawer-dropping drew about 8,000 revelers and was shut down for the first time in its history, said Jim Amormino of the Orange County Sheriff's Department.

"Things have gotten out of hand to the point of open sex acts and total nudity," Amormino said. "Last year was the first time we shut it down. There was a medical aid call and we couldn't get help in in a timely manner."

This year, city officials have teamed up with law enforcement in an enforcement campaign that includes new but temporary parking restrictions along Camino Capistrano that went into effect on Thursday and will expire on Sunday afternoon.

And don't think of carrying alcohol outside nearby Mugs Away Saloon, said city representative Meg Waters, where legend has it the tradition began in 1979 when customer K.T. Smith offered to buy a drink for anyone who would run outside and "moon" the next train.

Since then, on the second Saturday of each July, people have lowered their inhibitions and pressed their naked buns up against a chain link fence as the trains chug by.

Mugs Away, at 27324 Camino Capistrano, holds only 49 people, Waters said. "If it's full, you can't stand outside and drink," Waters said. "If you leave Mugs Away with a beer in your hand you're going to be arrested. If you're standing outside with a drink, you're going to be arrested. And if you think mooning is fun sober, well, I can't imagine that."

Whether any mooning will get past the watchful eyes of deputies that will be on-scene is not entirely clear. Waters said public nudity is against the city code, but she conceded that whatever steps are taken will be up the law enforcement.

"The rule of thumb is public nudity is not allowed," Waters said. "You can push that."

Amormino also hedged. "We're hoping for a nice peaceful day," Amormino said. "The ideal situation is no mooning at all. You may or may not be arrested for indecent exposure. It all depends."

"We'll see what happens and take it from there," Amormino said. "Our main concern is public safety," Amormino said. "If it gets in front of our faces, the law's going to be enforced."

Thirty-nine Amtrak and Metrolink trains pass the spot between 7:30 a.m. and shortly before 11:30 p.m., Amormino said.

Amormino said the event has grown to the point that people arrive in recreational vehicles and camp out in tents, beginning the night before. Waters said a sheriff's command post will be set up in the parking lot of the nearby train station, taking up much of the available parking in the area -- which usually was gone by 7 a.m. on mooning day, any way.

A Web site, MoonAmtrak.com gives driving instructions to the site, but also recommends arriving by Metrolink. The walk from the train station to the site is about 3/4 miles, according to the Web site.

The Web site gives helpful information, such as bringing flashlights or a camping lantern for "night mooning," and pointing out there are no street lights in the area.

The site emphasizes that no one is in charge of the event, there is no one to sue if anyone gets hurt and no one is carrying public liability insurance.

Waters said, "It's all over the Internet. That's part of what has grown it."

Bottom line: it might be easier to moonwalk as to moon.