Arlington officials have narrowed their search for a new jail site to two locations in the Court House area, just as the current jail is experiencing record crowding, County Manager Anton S. Gardner said yesterday.

One option is to build up to an 11-story jail at Court House Road and North 14th Street. The county now owns about 60 percent of the block and would buy the rest, Gardner said. The jail would be built on one side of the block and the rest set aside for future jail or court expansion or open space.

The other choice is to build on the current site of the Holmes Building along North Veitch Street between North 14th and North 13th streets. The county already owns the Holmes Building and some adjacent parking lots, Gardner said. However, Bell Atlantic, which has its headquarters on the same block, has expressed an interest in buying the county's land.

The plans have been submitted to the county Planning Commission for study. The County Board will decide this spring on the jail location and whether to place a bond referendum for about $20 million on the November ballot to pay for building a jail.

The board will also decide how to proceed with plans to expand other criminal justice facilities, including the courts, the police department and the commonwealth attorney's office.

The Maguire Group, a consulting firm hired by the county, has issued a report predicting that within the next 20 years space for the courts and police needs to double and that jail space needs to triple to meet anticipated demand.

The current jail, built to hold 164 prisoners, held a record 282 inmates at one point this week, said Arlington Sheriff James A. Gondles Jr.

"There just isn't any more room," he said. "Once you've reached that outer limit, you're asking for trouble."

Bunks have been put in rooms such as the law library, Gondles said.

In spite of the crowding, Gondles described the situation in the jail as "relatively calm."

Gondles said the growth in the inmate population stems from a variety of factors, including the rise in Arlington's daytime population of workers, crackdowns on drug dealing and the incarceration of Falls Church prisoners in Arlington rather than Fairfax County. Prisoners who would normally be sent to state prisons have also been kept in Arlington because of crowding in state facilities.

Both the original jail, built in 1974, and a $2 million addition finished in 1985 were at capacity as soon as they opened.

Gondles said current jail capacity must be doubled within 10 years and then plans for additions must be on the drawing boards "in five years and then another five years after that."

County Manager Gardner said wherever the new facility is built, "it is going to be expandable so we don't have the same problems again."