Montgomery County Executive Douglas M. Duncan has signed an unprecedented executive order authorizing construction of a neighborhood sidewalk, ending two years of rancorous debate over the need for one on Maryknoll Avenue in Bethesda.

His move marks the first time in the 35-year history of the annual sidewalk program, which installs sidewalks in neighborhoods developed without them, that a neighborhood dispute required an executive order to settle the issue.

It was not the first time that construction of a sidewalk has ignited a bruising neighborhood battle. But the conflict in Bethesda was so contentious, officials say, that it has prompted them to study changing the procedures for requesting sidewalks so that a handful of neighbors can't block construction of sidewalks needed for pedestrian safety.

"It served us well up to this point," said Richard Earp, an engineer in the county Department of Public Works and Transportation who heads the sidewalk program, "but it's time to take a look at it and see what we can do to improve community outreach."

Construction of sidewalks is a neighborhood flash point that often pits newer residents with young children against longtime residents who don't want a change in the character of an older community. Until 1992, Montgomery had no requirement that builders include sidewalks as part of development projects.

Each year, 80 to 90 neighborhoods submit requests for sidewalks, many of them citing safety concerns. The county currently spends $1.15 million a year building 15 miles of sidewalks, using a detailed application system to help officials sift through the backlog of 200 sidewalk requests.

Just to begin the process, residents must gather dozens of signatures and supporting letters from neighborhood institutions and civic associations. Before a final decision is made, county staff members meet with residents and study each site's engineering requirements, including retaining walls and transplanting trees and shrubs.

According to Earp, his office decided to review its procedures for approving sidewalks after the dispute between neighbors on and near Maryknoll Avenue pushed the sidewalk project into the hearing process.

There, a five-year resident who wanted to walk her children to school in safety requested a sidewalk nearly two years ago, bringing down the wrath of established homeowners who hired a lawyer after county administrators approved the request last June. The anti-sidewalk neighbors demanded a public hearing, which was held in August. The hearing officer ruled in November in favor of a sidewalk and Duncan signed the order on Dec. 20. Construction is scheduled to begin this month.

Though the rancor on Maryknoll Avenue was unusually fierce, similar flare-ups have accompanied sidewalk projects throughout the county.

Helen Dodson was so upset two years ago when the county approved sidewalks for her 30-year-old Olney Mill neighborhood, where she is one of the original owners, that she wrote to Duncan about the plans.

"His answer was, 'I will come down on the side of children,' implying that people who don't want sidewalks don't care about children and that's just not right," Dodson said. "Everyone cares about children. But two generations of children made out fine without them."

While Dodson feels the process was unfair -- the county went ahead and built the sidewalks -- residents in other neighborhoods who want sidewalks find the process overly cumbersome, with too many opportunities for opponents to derail needed projects.

"It's long and drawn-out and you have to constantly follow up," said Anne McDermott, who over a decade helped get sidewalks on several blocks of her Woodside neighborhood in Silver Spring. "It's a burden for the neighbors to be constantly asking, asking, asking but you have to because things fall through the cracks. You need a volunteer in your neighborhood who will stay with the county through the process."

Monica Ettinger, who leads a project to improve safety for students who walk to Rolling Terrace Elementary School in Silver Spring, agrees that dealing with the county government can be "painful."

"We want sidewalks and we want them now but that's not how it works," she said. "You have to learn to manage the beast. It's been a real learning experience."

County staff members have put together a brochure explaining the process, which outlines steps that must be followed to present a formal proposal.

"We don't take a single property owner's request," said Bruce Johnston, head of DPWT's Division of Engineering Services. "If that's all that comes in, it goes on the bottom of the list. We suggest they try to get community support."

The department also gives higher priority to projects within walking areas to schools or other public facilities such as parks, libraries and mass transit, and those that connect with existing sidewalks. Once promising projects have been identified, county officials notify all the neighbors, giving them a chance to respond.

This is often where the process bogs down.

Residents who have managed without sidewalks for decades don't want the sudden responsibility of shoveling snow. Many have developed a sense of ownership of the right of way. Earp tries to work with residents who are unhappy with a sidewalk proposal and will often agree to move or work around trees or other plantings.

"I spend a good portion of my time out in front yards discussing where sidewalks are going to go," Earp said.

But some problems are knottier than others.

In Silver Spring's Forest Glen neighborhood, residents thought their request for a sidewalk on the north side of Holman Avenue was a no-brainer because it would ease the walk to the nearby Metro station for residents of Glen Briar condominiums.

The surprise opponent was the county's Historic Preservation Commission, which said a sidewalk along the side yard of a Victorian house on the proposed route would be historically inaccurate. The commission suggested moving the sidewalk to the south side of the street. But residents opposed that idea because it would have required the removal of trees and construction of a retaining wall and, even then, would have required pedestrians to cross a busy street to use the sidewalk, thus compromising pedestrian safety.

After months of phone calls, letter writing and a contentious public meeting, at which residents showed turn-of-the-century photographs of local homes with sidewalks, the commission decided against a sidewalk on the south side of Holman Avenue. But it did not reconsider the original request for a sidewalk on the north side.

"We feel bad right now because there's a lot of people who use the Metro and a huge population of toddlers getting ready to go to school," said Nancy Mendez, who began working to get a sidewalk more than three years ago. "It would be really nice to have a sidewalk and now it looks like we're not going to get any sidewalk at all."

After a bitter battle, parents and students walking along Maryknoll Avenue will soon have a sidewalk on their way to Burning Tree Elementary School.