Members of several north Silver Spring civic associations have joined ranks to fight plans for what they see as unnecessary and potentially ruinous road widenings in their residential areas.

The proposed changes, part of the Montgomery County Department of Transportation's capital improvements plan, would widen Brookville Road between Warren Street and Linden Lane from its present 24 feet to 48 feet and reconstruct the intersection of Seminary Road, Second Avenue, Linden Lane, Brookville Road and Seminary Place.

The project would channel traffic from Brookville Road and Linden Lane into three eastbound lanes moving towards Georgia Avenue on Seminary Road. Second Avenue, Seminary Place and Seminary Road would all be widened and the existing islands trimmed. The plans also call for sidewalks and crosswalks to ease pedestrian travel by school children and future users of a proposed Montgomery Hills Park next to the intersection.

Residents charge that the $4 million project would violate the spirit, if not the letter, of the North Silver Spring sector plan approved by the County Council in July 1978. The sector plan states that "between Warren Street (the B & O Railroad lines) and Linden Lane, Brookville Road should be improved to at least a 36-foot paving . . . Actual width should be determined primarily based on safety factors, since traffic volumes do not indicate the need for a full 48 feet of paving."

Steve Tarkington of Second Avenue argued that transportation department traffic counts made between 1974 and 1979 back up his contention that use of the roads in the area is decreasing.

Residents of the area, which is wedged between the Beltway on the north and the major arteries of East-West Highway on the south, and 16th Street and Georgia Avenue on the east, fear that upgrading existing roads will bring more cars into the area.

Residents who took part in the initial drafting of the sector plan contend that the clause "at least 36 feet" was included to allow for tapering the roadway down from an already constructed 48-foot bridge at Warren Street to two lanes on the rest of Brookville to Linden.

Engineers say that it is illogical to have a 36-foot road leading to and away from a 48-foot bridge. Jerry Clichy, Department of Transportation director, said that "48 feet is our standard width for an arterial street. There are many vehicular and constructio trucks on that road and this width makes sense."

Transportation department engineering chief Robert C. Merryman sees the purpose of the project as emphasizing "safety rather than capacity." He said that there are many points where cars can cross paths and perhaps collide in the present configuration of the Linden Lane, Seminary Road and Second Avenue intersection. "Our proposal seeks to minimize these points of conflict," he said.

"The plan is viewed as a pedestrian advantage," Merryman said. "The intersection has a unique array of islands, and if pedestrians know which direction the cars are going, then they can avoid them."

Whether it makes good engineering sense or not, residents of Montgomery Hills, North Woodside and Linden are amassing their own statistics to counter DOT's arguments at the public hearing scheduled for 7:30 p.m. next Thursday in the Maryland-National Capital Park and Planning Commission offices at 8787 Georgia Ave. in Silver Spring.

If the road changes are approved, construction could begin as early as next spring, because the County Council has already appropriated money for the initial stages of the project.

Representatives of the Maryland National Capital Park and Planning Commission are expected to testify at the hearing next week in opposition to the county plans. In September 1978 commission chairman Royce Hanson sent a letter to the county transportation department recommending that the sector plan be followed more closely. Specifically, the commission recommended a 36-foot width for the stretch of Brookville Road between Warren Street and Linden Lane; that Second Avenue be classified as a secondary residential street and not widened, and that Seminary Road be widened only between Georgia Avenue and the western limits of Montgomery Hills commercial district.

While residents of the area hope to forestall the road widening, they said they also hope to convince the county transportation department to pay more attention to citizen opinions.

"If we'd been in on this from the outset, everyone would have been saved a lot of grief, tears and money," said June Rogul of the Linden Civic Association. "As it was, we had to do all the digging and researching ourselves, just to uncover the plans."

After the public hearing, the record will remain open for about a month to admit any additional testimony that may be offered, according to a county official. Then the hearing officer will make a recommendation to County Executive Charles W. Gilchrist, who will decide whether to go ahead with the project.