As the region's drought worsens, officials on opposite sides of the Potomac River are squabbling over whether people should be asked to take shorter showers and stop watering their lawns, even though all agree supplies are adequate to meet everyone's needs this summer.

The Washington area has been short of rainfall for a year, and river flows are at record lows. This week, for the first time, regional officials authorized release of more than a billion gallons of water stored in upriver reservoirs to offset the drought's effect on the Potomac River near Washington.

That water from Jennings Randolph Lake and the Savage River Reservoir, released by the Army Corps of Engineers beginning last Sunday, is expected to arrive in the Washington area by today. It's not needed to supply drinking water--there's enough water in the river to do that--but to make sure there is enough flow to protect Potomac River fish and other species.

As an illustration of how low the Potomac is, consider these figures: The Interstate Commission on the Potomac River Basin says that the region is using about 500 million gallons of Potomac water a day, its normal summer demand. The Potomac's flow is at about 600 million gallons a day. That leaves 100 million gallons of extra water, the minimum considered necessary to protect life in the river. Water being released upstream will make sure that level doesn't drop.

The commission's worst-case supply-and-demand forecasts indicate that rivers and reservoirs supplying the District and most of suburban Maryland and Virginia have enough water in them to last the summer, even without use restrictions.

"There is enough water," said Erik Hagen, water resources engineer for the commission, which tracks water use and river flow daily. "It's not an emergency."

But the drought has reignited debate over whether that 100-million-gallon level is really adequate to sustain life in the river. The League of Women Voters earlier this year called for more study of whether the level should be set higher, and the Audubon Naturalist Society asserts that it is not high enough to protect the environment. Just to be safe, the region should cut back on water use, some environmentalists say.

Montgomery County Executive Douglas M. Duncan (D)--who asked county residents Monday to begin voluntary water conservation measures--is pushing other localities to do the same.

Duncan urged the Metropolitan Washington Council of Governments on Wednesday to adopt a resolution favoring voluntary water conservation throughout the region. But the local politicians on the council softened the resolution--with phrases including "as appropriate."

"There was more reluctance on the Virginia side to weigh too deeply into this without hearing more from the technical people," said Gerald E. Connolly, a Fairfax County supervisor. "What we're hearing . . . is it's too premature to call for voluntary conservation."

"I was concerned that we might be crying wolf, and so therefore we needed to be more prudent in the approach that we took," said Penelope A. Gross, also a Fairfax supervisor.

Duncan's specific concern is that the drought might eventually require releases of water from 450-acre Little Seneca Lake, a popular park in Germantown that is also a regional reservoir.

Lowering the lake's water level could cost the county about $125,000 in boat rental and mooring fees, according to the Maryland National Capital Park and Planning Commission. Officials say it also would endanger bass and sunfish hatcheries, kill creatures from turtles to tiny crustaceans, and create smelly mud flats.

"We'd like to see the water drawn from the other two sources [upriver reservoirs] and conservation used before going to the smallest lake where the impact would be the biggest," said Marion Joyce, commission spokeswoman.

So far, Fairfax City has had to impose restrictions to conserve supplies in its one low reservoir. Well users are also having problems throughout the region.

The Fairfax County Water Authority, which also sells water to Aleandria and Prince William County, decided last night to advise customers to be prudent in their water use and encourage water conservation, according to James Warfield, the authority's executive director. But the agency didn't recommend implementation of water restrictions because there has been no declaration of a water emergency.

The Army Corps of Engineers, which operates the District's two treatment plants, told city officials that "the District's water supply is quite ample, and there is no need to put any type of water conservation in place," said Libby Lawson, spokeswoman for the D.C. Water and Sewer Authority. But low water levels at Great Falls have forced the Corps of Engineers, for the first time ever, to abandon its gravity-fed intake and use pumps at Little Falls to move water into city aqueducts.

The Washington Suburban Sanitary Commission, which serves Prince George's and Montgomery counties, will consider a water conservation measure on Wednesday.

Some question whether voluntary restrictions do more harm than good, by causing neighborhood conflicts and reducing the impact of a mandatory save-water order, should it be needed later. Already, officials said, people have misunderstood Duncan's call for voluntary restrictions.

About two dozen customers called the WSSC office Wednesday saying they absolutely had to water their flowers or wash their patios, spokeswoman Marjorie Johnson said.

"Some people are thinking it's mandatory now," she said. "They are not hearing the word 'voluntary,' which was what was said."

Some officials and environmentalists say there is good reason to conserve water now, drought or no. It avoids the need to build more reservoirs later, by holding down demand now.

"Why aren't we being asked to conserve?" asked Katherine Mull, an activist with the Friends of Sugarland Run. "I know they say there is a supply, but the drought might last longer than we expect. And it's a waste of resources to squander water."

Drought Relief

Regional officials authorized the release of more than a billion gallons of water stored in reservoirs far upstream to relieve drought conditions near Washington. The water, expected to reach Washington by today, has been traveling downstream since Sunday.

CAPTION: A dead fish lies at the edge of Alexandria's Oronoco Cove at low tide. Environmentalists say more of the Potomac's water must be shielded from human consumption to protect fish and other wildlife that depend on it for survival.

CAPTION: At Alexandria's Oronoco Cove, which has been turned into a mud flat by record-low flows in the Potomac River, a catfish struggles during low tide.

CAPTION: While a heavy drawdown on the Potomac has left humans unaffected, a far greater impact has been felt by plant life along local waterways.

CAPTION: (Photo ran in an earlier edition) In a bid to help parched areas such as Oronoco Cove in ALexandria, the Army Corps of Engineers has released a billion gallons of water into the Potomac from two upstream reservoirs. The water is scheduled to reach Washington today.