A special interest group -- this one sporting power tennis shoes rather than sleek ties -- has successfully coaxed Prince William County into taking a leap no other Washington area jurisdiction has dared: to build a publicly operated skateboard park.

Prodded by the teenagers, county officials are planning to construct a $50,000 skateboard facility at Veteran's Memorial Park near Route 1. The park, partly financed by a developer contribution and scheduled for completion by the end of the summer, is expected to draw skateboarders from the metropolitan region.

"I think we're doing something kind of pioneer," said Stewart Christiano, chairman of the Prince William Park Authority, which will operate the park. "Yeah," said Chris Lyman, 18, one of the skateboarders who approached county supervisors two years ago, "Prince William is on the cutting edge of skateboard technology."

Across much of the country, skateboarding on public streets and pathways is illegal, forcing enthusiasts of the sport to build private ramps or use shopping center parking lots and other paved open spaces. In recent years, however, many shopping center owners have banned skateboarding.

But some Prince William skateboarders said they have ignored the laws, going "anywhere and everywhere."

"There's a demand to get these children off the streets," said Supervisor Hilda M. Barg (D-Woodbridge).

Park officials from area jurisdictions have shied away from publicly run skateboard parks, primarily because obtaining liability insurance for what is considered a high-risk facility is difficult and expensive.

But Prince William, and other counties and cities across the nation, resolved the insurance issue by putting the skateboard park under a self-insurance fund. Several county agencies contribute to the fund, which totals about $500,000 for casualty insurance. The county also has a commercial policy to help cover claims.

There are about 80 indoor and outdoor parks for skateboarding in the United States, according to Katie White of the California-based National Skateboarding Association. The sport, said skateboarding experts, began flourishing in the mid-1970s after the introduction of a more resilient, faster urethane wheel for the skateboard.

About 30 percent of the country's skateboard parks are publicly operated or run by nonprofit organizations, such as the Boy Scouts or YMCA clubs. But White said the number of publicly run parks is "definitely going up."

Seven publicly run parks operate in the East, including Ocean City, Md., and Virginia Beach. There is a privately run ramp at Cedar Crest Country Club in Centreville, which is open to the public.

In 1989, about 65,800 skateboard-related accidents were treated at hospitals across the country, according to the Consumer Product Safety Commission.

Many of those accidents occur outside supervised skateboard parks, which require protective equipment, according to Tom Perlozzo, director of Ocean City Parks and Recreation and author of a guide to developing skateboard parks. The skateboarders "are more reckless on the streets than they are in the facility." In 1989, Ocean City's park, for example, had about 30 reported accidents, Perlozzo said. Four included major injuries, such as broken bones.

For Prince William, the main stumbling block to building the skateboard park was finding the money to build it, officials said. But in February, Barg proposed the county use $30,000 a developer donated as part of a rezoning to help build the park. Future developer contributions will probably cover the remainder of construction costs, Barg said. User fees and park authority funds will pay for operating expenses, estimated to be $13,000 annually.

To avoid lawsuits over accidents, Prince William park officials said skateboarders will be required to sign a liability waiver form. The park will be surrounded by a fence, skateboarders will be required to wear protective equipment and a supervisor will be on duty.

The park will have a steel half-pipe with 11-foot sides, a concrete or asphalt bowl, and for the street riders, a curb and set of steps.