Detta Harding's neighbors in Silver Spring used to think of her as a relaxed, easygoing woman, someone who always had time to make macrame wall hangings or reweave the caning on broken chairs.

For the last few months, ever since Harding learned that Montgomery County officials wanted to build houses along the nearby creek, she often has not had time even to wash her clothes. She wakes up at 4 every morning, spends hours clipping articles from newspapers, and stuffs them into shopping bags that she carries with her. Then she drives from county agency to county agency, talking to officials who speak her language -- the language of watershed studies and storm water management and flow charts and hydraulics.

"I used to look at Sligo Creek and think 'pretty,'" Harding says. "Now, I see the creek and look for erosion and sediment and riprap."

Harding is one of hundreds of Montgomery County citizens, most of them women, who are intensely devoted to such arcane subjects as landfills, sewers and storm water management. In most cases, they want to stop the county from building landfills, compost facilities or sewers in their neighborhood. These women, who have come to be known as "the sewer ladies," spend their days learning about the technical details of the projects so they can explain the particular project's failing to officials.

Every day, they wander in and out of county offices, talking to county engineers, planners, lawyers and elected officials. At night, they do more research, reading textbooks and examining maps and charts. Always, they are present at County Council work sessions or public hearings, willing to testify or to politely inform an official that he made an error in computation. t

Officials in Montgomery County do not think of such behavior as unusual. In Montgomery County, citizen participation in goverment is almost a natural reflex, like driving to shopping centers.

"In this county," explained Linda Fohs, an official in the Office of Environmental Planning, "everyone gets in on the decision making."

This is after all, the county that has a shadow government of 42 citizen advisory committees whith nearly 600 active citizen members, several hundred more than any other metropolitan area county.

This is the county where County Council meetings and school board meetings attract as many residents as the movies.

This is the county that spent thousands of dollars to send 12 citizens to Muskegon, Mich., entrusting them with the task of advising council members on whether Muskegon's system of land treatment of wastes could be used in Montgomery.

"Other counties also have people who participate in government," said county Chief Administrative Officer Robert Wilson, who also has worked in Prince George's County and Fairfax. "But not in such numbers."

County officials say that the amount of citizen participation in Montgomery is due, in part, to the jurisdiction's affluence. They say that residents have spent huge sums of money on their homes, and they do not want the government to make decisions that could lower their property values or blight their neighborhoods. In addition, the county has a large population of well-educated women who do not work at nine-to-five jobs and have the time to devote to learning about sewers and landfills.

Another explanation, officials say, is that many of the "Sewer Ladies" are related to, or married to, federal government employes. "We have a lot or people here who know how government rules and regulations work, and want to make them work for them," said Fohs.

Officials in Montgomery like to say that the amount of citizen participation in government there keeps the government open and honest. They also say that the "Sewer Ladies" questions and arguments can result in hours of extra work for them.

"These women who come in our offices make bureaucrats sit up and listen," said David G. Sobers, director of the Office of Environment Planning. "Frequently the bureaucrats will tell their staffs to go back and do more work to satisfy the women's questions."

"One guy in this office," said Steve Profilt of the Washington Suburban Sanitary Commission, "has gone over computations hundreds of times, and just for one woman."

The practice of women analyzing technical data on proposed projects to lobby against them began in the county in the early 1970s when citizens from all over the county began protesting against plans to build a $400 million sewage treatment plant at Dickerson in the upper county. Most of the women opposed the plant because they believed that the tremendous increase in sewage capacity would result in increased development throughout the county.

Officials came to call the women "sewer ladies" because, in arguing against the proposed plant, the women acquired an intricate knowledge of the diameter of every sewer pipe in the county, where the pipes were located, the amount of the water pressure operating in them, and what it all meant in terms of development.

The most celebrated "Sewer Lady," Charlotte Garnett came to prominence then. Gannett, who died last year, was a short brown-haired Chevy Chase housewife who spoke with a rapid-fire Southern accent. She always walked in county offices and hearing rooms carrying cardboard boxes full of technical data.

"She looked like a simple housewife who was great at scrubbing bathroom floors, but she was a mental giant on all that technical junk," said County Council member Rose Crenca. "She'd invite people over to her house and show them movies of waste treatment. Then she'd give me these thick technical volumes on sewage and tell me to read them before I saw her again."

Gannett would interrupt County Council meetings, work sessions and public hearings to distribute her own statistics and information on the proposed sewage plant. When she disagreed with a council member's interpretation of the data -- which was often -- she would interrupt the meeting again and correct the speaker.

"Charlotte Gannett was presistent," said council member Elizabeth Schull.

"There has been no one quite like her since."

In the end, Montgomery County did not build the sewage plant. County officials believe that Gannett, more than anyone else, was responsible for persuading the Environmental Protection Agency to refuse to give the county the necessary permit.

"We look at the EPA's files, and they were replete with letters and references to meetings with Charlotte Gannett," said Sobers. "She visited them constantly."

In Montgomery, sewers are not the big issue they once were. But latter-day "sewer ladies" still roam the county, analyzing data in an attempt to stop proposals for landfills and compost facilities and public housing in their neighborhoods.

Part of the reason they must analyze so much data is that, in Montgomery County, residents do not argue against landfills on the grounds that they do not want to live near landfills. Instead they argue against the geometry of the proposal, saying that the water table of the ground at the proposed site is too high for a landfill, that birds attracted to the landfill will be a hazard for airplanes, and that the farmhouse on the proposed site has historic value and must remain there. The more angles there are, the better the chance of blocking any one proposal.

"There's a key to stop this thing," fretted Priscilla Benner of Laytonsville, who is fighting the proposal to build a landfill near her home. "The water table should have been the key but may not be. The historic house could be the key. We have to find the key."

For the last two years, Benner has spent 40-hour weeks visiting officials about the proposed landfill, analyzing data on it, and testifying against it at hearings and council meetings. Three years ago, she would not have believed that she would ever become an expert on landfills. Today, she rattles off details on them as though they were as familiar to her as her children's names.

"Landfills create methane," she says. "And if you have a porous soil, the methane gas can migrate through the ground and into someone's basement. It can cause explosions.

"Another issue," she says. "Rain coming through garbage creates leachate. Leachate is thick and green and putrid. It will contaminate our well water. The soil at the landfill site isn't the proper soil for attenuating leachate."

Across the county, in Silver Spring, Detta Harding also spends at least 40 hours a week visiting county and state officials and testifying at hearings. 4Harding's field of knowledge is storm water management. She acquired it because she does not want the county to build public housing along Sligo Creek, and she wants to show that buildings there will cause greater flooding and erosion during storms.

Unlike Benner, who by now has found all of the issues she needs to argue against the landfill, Harding is still searching for more issues to use against the public.

On a recent afternoon, she drove from her home to Annapolis to ask the state archeologist Tyler J. Bastian, if the area along Sligo Creek would be valuable for archeological digs.

"Do you think Sligo Creek has prehistoric potential?" Harding asked him, notebook in hand. "We're looking for justification to save the area from development."

The archeologist told Harding that the area has "moerate prehistoric potential" and that the county could not opt to fund an archeological survey to test whether artifacts were buried along the creek.

Harding finally left, content that she had another angle to raise when she visits county planners, engineers, lawyers and elected officials.