One too many flushes of the toilet, a little too much luxuriating in a hot shower, a house full of guests--that's all it takes for the people on Peach Tree Road to lose their water altogether.

Living on a rocky ridge in the northern Montgomery County community of Clarksburg, about 100 homeowners who rely on wells are accustomed to intermittent water and lousy water pressure.

So they're not terribly keen about the prospect of a new neighbor--a golf course--whose fairways and greens might quaff as many as 110,000 gallons of underground water a day, more than five times the little neighborhood's current daily usage.

"Picture this: It's Labor Day, it hasn't rained in six weeks. They're watering like crazy to keep their beautiful greens green," said Tom Hoffman, who heads the Clarksburg Initiatives Association, one of several groups opposing the course. "That's going to affect me. I won't be able to give my daughter a bath or myself a shower or my horse a drink."

The course's developer says nothing of the sort will ever happen. But that hasn't stilled the water controversy, one of several that have gushed up in rural and suburban Maryland and Virginia this summer, prompting concern about the impact that development and drought might be having on water supplies.

* In Poolesville, the summer's prolonged drought has so depleted the water table that town officials have imposed mandatory water restrictions, and some residents have argued that development ought to be restricted as well.

* On High Knob Mountain, near Front Royal, Va., several residents are running out of water and complain that the developer never told them drought conditions would mean the toilets in their weekend homes would have to be flushed with buckets of water.

* In Beaver Creek, Md., in Washington County southeast of Hagerstown, a quarry's expansion plans have drawn fire from residents who say the company's activities threaten wells and the underground spring that feeds the state's major fish hatchery.

* In Windsor Knolls, a high-end subdivision being built in fast-growing Frederick County, officials halted construction last month after the community's well water reached a dangerously low level.

* In Walkersville, also in Frederick County, workers laying utility lines for a new development last month shattered a sewage pipe, spilling nearly 900,000 gallons of raw sewage into the town's wells.

"Urban sprawl is causing these kinds of competing demands for groundwater, these conflicts," said Jim Gerhart, of the Baltimore office of the U.S. Geological Survey. "The more growth, the more conflict. And the drought doesn't help."

The water table across the region has dropped to unprecedented levels, Gerhart said. One of the agency's six test wells in the region is the lowest it has ever been. The Monocacy River has reached its lowest flow ever.

All that, environmentalists argue, represents one more reason government needs to limit development. "Droughts like this just bring the crisis home sooner," said Chris Bedford, who heads the Maryland chapter of the Sierra Club. "We've got to think about the limits to our water supply before we just give it away to any developer."

In Clarksburg, the proposed Bucklodge Hollow Golf Course--whose water-use application is pending with Maryland environmental officials--threatens to exacerbate the water troubles of the ridge-top neighborhood of 100 well users, residents say.

"The first year we moved here, we planted trees, watered them," said Melane Hoffman, "and that day our well went dry."

Now, the Hoffmans keep bowls under dripping faucets and scoop out the water from the kiddie pool for houseplants. And there is no lawn or garden watering. Some neighbors rent portable toilets when they have family parties. Others have basements equipped with barrels of emergency water. Almost everyone has an explicit toilet-use policy, often posted over the tank.

"You don't flush until it becomes objectionable in there," said Tom Bartel, putting it delicately.

The Bucklodge course, which developer Hossein Forooshani, of Potomac, has been working on since 1991, would be an 18-hole public golf course on 212 currently wooded acres. The site is between Peach Tree and Slidell roads west of Clarksburg in Montgomery's rural up-county, where much of the zoning is extremely low density. The developers' consultants say nearby residents have nothing to worry about because there is no significant underground connection between the golf course site and the dense, high rocky area where most of the neighbors live.

"We believe that between the wells we will drill and the two big lakes where we plan to store water, we will have more than enough water," said Robert H. Metz, the Silver Spring-based attorney for Forooshani.

Based on early comments, state environmental officials who are reviewing Forooshani's application agree that the golf course will not unreasonably affect residential wells. But Quentin Banks, spokesman for the Maryland Department of the Environment, said that no decision has been made and that the matter is still under review.

The developer has offered to conduct regular monitoring and to drill a new well if necessary. That was cold comfort to residents.

"Once it's built, it's built," said Dolores Milmoe, of the group For a Rural Montgomery. "They're not going to shut it down if problems show up after the fact."

The residents' consultants, who include a hydrogeologist for the U.S. Environmental Protection Agency, dispute the developers' testing methodology and computer modeling. They also dispute the estimate of the orientation of the major underground rock fractures in their part of the Piedmont formation, the geological zone that spreads over most of the county and western Maryland.

Residents are also concerned that the developer has significantly underestimated the golf course's likely rate of water consumption. County officials agree.

"Based on our experience with other golf courses . . . an 18-hole course, just to irrigate the tees, fairways and greens in a drought summer month, will use 300,000 to 450,000 gallons per day," James Caldwell, director of the Montgomery County Department of Environmental Protection, wrote in a letter to the state.

Residents also worry about the herbicides, pesticides and fertilizers that might run off the course and into several streams and, ultimately, reservoirs and the Chesapeake Bay watershed. Among the streams with headwaters at the site is the Bucklodge branch of the Little Seneca.