Prince George's County Executive Parris Glendening has asked the County Council to support a controversial proposal to reroute a heavily traveled road through a section of historic College Park Airport, described as the oldest continuously operated airport in the United States.

The highway project, estimated to cost $21 million, would provide an alternate route for a section of Calvert Road, a main throughfare for the densely populated College Park-Hyattsville area that is being rerouted because of Metro Green Line construction scheduled to begin in the area late this year.

Glendening's proposal, sent to the council last week, follows years of controversy surrounding the realignment of the road, which cuts a path across College Park from Rte. 201 to Rte. 1 south of the University of Maryland campus.

"{The route} represents a selection of an alternative that best suits the public interest," said James Novak, director of the county Department of Public Works. "Because of time constraints, we need to go forward."

College Park officials, historic preservationists and at times the federal government have opposed rebuilding the highway north of the existing route so that it ends at the University of Maryland campus gates on Rte. 1 -- the path favored by Glendening. The northern route would slice a half-acre off the College Park Airport, which opened in 1907, and come within 18 feet of where original plane hangars stood. The airport was recently added to the National Register of Historic Places.

A modified version of the proposal would build the road 180 feet to the south, but would destroy a half-acre of a city-owned park. When negotiations for the park land broke off in December, Glendening opted for the airport route.

County officials said the northern route is the best alternative because traffic surveys show that 75 percent of vehicles using Calvert turn north at Rte. 1. They said the road would not affect airport operations.

However, College Park officials favor a route that would take the road south of the existing alignment to intersect with Rte. 1 south of Queens Chapel Road because it would provide the shortest distance across a city park and cause the least environmental damage.

The delay in selecting a new route for Calvert Road means that when the highway is closed later this year, there will be no new road to take its place. About 18,000 vehicles will be funneled to Rtes. 410 and 193, which already experience rush-hour traffic problems.

"That's one of the points we've been trying to emphasize is the time constraints are unalterable," said Glendening spokesman Tim Ayers.

If the council and the Federal Highway Administration approve the proposal, county engineers in the fall will begin designing the road, which is expected to take about 1 1/2 years. Construction will begin after the county buys rights-of-way, including 16 small businesses on Leigh Road, and should take about two years.