The St. Mary's County commissioners decided this week not to add land to the 17,000-acre Lexington Park development district.

More than 6,000 acres had been proposed for inclusion in the district -- an area in which concentrated growth is allowed -- including the grounds of the Patuxent River Naval Air Station and several pieces of property whose owners wanted them included in the service area of the county water system.

All of the commissioners except for Commissioners President Thomas F. McKay (R-At Large) voted to retain the boundaries.

"We don't need to create a South Waldorf, so to speak," said Commissioner Larry Jarboe (R-Golden Beach). "There's no reason to make this development district bigger."

McKay said the decision was "shortsighted." He said it indicated that some of his colleagues were "lacking the vision and understanding [of] Lexington Park" and that the support for maintaining the boundaries arose out of "just not having the will to make some tough decisions."

McKay argued that Myrtle Point, an environmentally sensitive area known for its steep slopes and erodible soil, could be taken out of the development district and that land more appropriate for building could be added. But Jarboe said after the meeting that it was the first he had heard of such a swap and that all previous proposals were to add land.

"There is a time to just say no," he said.

Lexington Park, which is west and north of the Navy base, has grown steadily in recent years as military jobs have poured into the area. From 1990 to 2000, Lexington Park's population grew 13.9 percent to 24,104, and it is projected to grow an additional 30 percent by 2020. The commissioners' decision came as part of a review of the county's 1999 comprehensive plan, a process that will lead to a major rezoning.

The plan "has huge influence, not just over Lexington Park . . . [but] over everything that happens in St. Mary's County land-use wise," McKay said.

The decision to retain the boundaries kept several pieces of land on the district's perimeter ineligible for higher-density development, including a 75-acre parcel known as the Beavan property and three parcels totaling 357 acres west of the Wildewood neighborhood.

Much of the land that would have been added is on the Navy base. Including that land in the district would have made the process of applying for some grants smoother, said Sue Veith, an environmental planner in St. Mary's.

But officials from the Maryland Department of Planning had said that the development district was "much larger than the total projected growth requires," Veith said, and that adding the base "just makes that appear to be an even bigger issue."

The new master plan calls for creating a more pedestrian-friendly downtown with ground-floor shops topped by apartments. A 240-acre mixed-use zone that would be the focus of the effort is slated for the area off Great Mills Road that includes St. Mary's Square.

Also on Tuesday, the commissioners approved the transportation plan within the development district. A major goal is to improve access to the Navy base and divert some traffic off Route 235, especially around Route 4, which county Planning Director Denis Canavan described as a "failing intersection."

Roads scheduled to be built include an extension of FDR Boulevard from Willows Road to Wildewood that would run parallel to Route 235.

Another road would extend from Pegg Lane to FDR Boulevard, though the commissioners said they would like it to go even farther, to Route 235.

Of the transportation plan, McKay said: "It is a good vision, and sometimes it's hard to make visionary decisions. They're tough. But that's what people put us here to do."