The Huntington Bridge, which has carried traffic across the railroad lines in Bowie for 54 years, is getting too old for the task and will be replaced in six years. But figuring out with what and where -- without totally disrupting life in the center of Bowie's oldest shopping area -- is going to be burdensome, merchants and residents say.

State highway officials contend that the two-lane bridge on Chestnut Avenue, which carries about 13,000 vehicles and hundreds of pedestrians daily, will have to be torn down by 1991. But nearby residents say they are beginning to think that none of the alternatives proposed by the State Highway Administration will do.

"You get used to a way of life here," said Dorothy DiGregory, who has lived a few blocks south of the bridge since 1941. "I'm looking at it as a part of our town -- my friends and neighbors live across the bridge, the community center is across it, and so is the church."

Four of the town's churches are located just north of the bridge, as are banks, the post office, a fire station, service stores and antiques shops.

South of the bridge are more antiques shops, a grocery store, and the homes of hundreds of town residents who use the span to cross the tracks on foot.

DiGregory said that when the bridge was closed for six months for repairs two years ago, it was "a real disturbance." Traffic was detoured for more than five miles, she said.

Michael Synder, project engineer for the highway administration, said replacing several supports and paving the surface two years ago cost $100,000 and added 10 years to the life of the bridge.

Since then, vehicles weighing more than 20,000 pounds -- loaded drump trucks weigh about 60,000 pounds -- have been banned.

All of the alternatives to the bridge proposed by the state would cost $2.1 million to $3 million, officials said. The most disruptive -- rebuilding the two-lane structure -- would require closing it for 18 months, Synder said.

"You close that bridge for 18 months and this town is gone," said James Kram, owner of Clocks and Things, a shop at the southern end of the bridge. "Many of the residents simply don't own cars," said Kram, who has been acting as a spokesman for the merchants. "They're elderly or lower income. How do they get across?"

Other alternatives for reconstruction are more acceptable to residents and merchants, but new retaining walls required would block properties at either end, including Kam's store.

Another alternative calls for building the bridge east of its present site, which would require knocking out a house on Chestnut Avenue, and obscuring another with a retaining wall.

The highway administration will decide, and has scheduled another in a series of hearings for Feb. 22, Synder said.

"Right now none of the alternatives seems to be good," Kram said. "I suppose it's a matter of going with the lesser of the evils."