It shimmers at the intersection of Colesville Road and University Boulevard in Silver Spring, wavy and foreign, like a Death Valley apparition. There's something ephemeral about it, but something familiar, too.

"At first, I thought it was a mirage," Susan Starr says.

It's no mirage. It's water, that rarest of commodities today: hoarded, thirsted after, drilled for and, at this crossroads just outside the Capital Beltway, apparently bubbling up from underground and darkening the roadway. Since Tuesday, some sort of problem with a buried Washington Suburban Sanitary Commission water pipe has created a little oasis right here in Four Corners.

But a water leak, usually considered nothing more than a nuisance, is freighted with symbolism in this summer of drought, when residents are being ordered to conserve. As their shrubs shrivel, here is a precious liquid ebbing on the asphalt.

"My God, here I am at home trying to find all kinds of creative ways to conserve water, and there it is going down the road," says Celeste Puppolo-Orestrom, as she shops for a doggie chew toy at the nearby Pet Supplies Plus. "It just vitiates all our attempts to conserve."

Over at the 7-Eleven, reading the paper in the parking lot, Jeff Vaughan, 49, of Silver Spring, has noticed the leak, too. "It's not setting a good example, that's for sure," he says.

Inside the convenience store, assistant manager Jerry Ogunyomade, 36, is quick to stress that he's not responsible for the ever-widening puddle. "There's nothing we can do about it," he pleads. "It's not leaking from our premises." (Note to 7-Eleven corporate headquarters: It looked like one of the sinks had a slight drip.)

"I saw it yesterday," says Starr, 55, who stopped at the 7-Eleven for a cup of coffee. "I know WSSC. It takes them forever to respond."

Looking at the water makes her sad, Starr says. "It makes me think of the farmers and their loss."

Outside, water has pooled in a sewer cover in the middle of the road; every time a car goes by, a refreshing-looking rooster-tail of water is flung high into the air. There's the strangely pleasing--and now seldom heard--sound of tires on wet pavement: schweeet, schweeet, schweeet.

"That's a nice sound, isn't it?" says Dave Goad, 37.

Goad is here to silence that sound. He's part of a five-person WSSC crew that's waiting until the morning rush hour is over before it closes two lanes of traffic, then uses a backhoe to pierce the roadway in search of exactly what it is seven or eight feet down that's leaking.

Goad thinks it's a cracked 20-inch main, or a valve that's gone bad. He estimates it will take him three hours to open up the pavement and eight to 24 more for the flow to be staunched.

Goad recognizes the public relations dimensions of The Leak, how desperate measures for desperate times can seem a bit punitive and arbitrary--a bit paradoxical--when WSSC itself is letting some of the irreplaceable resource evaporate under the wheels of commuters. "I'm sure a lot of people are driving by and saying, 'Look at all that water!' "

But, Goad says, it really isn't that much water. "We consider that a little leak. It just looks bad because the cars are spreading it as they drive by."

It is pointed out that the WSSC truck Goad is driving looks suspiciously clean. The baby blue bodywork of the cab seems to have a showroom shine. Dave, you haven't washed this truck, have you?

"Oh no! The water company wouldn't do that," he protests. "We'd definitely make the news if we did that." He points to the back of the truck. "You can see the mud on the bed. It needs a wash."

So conscientious is WSSC, says Goad, that the crews are not allowed to hose off their work sites, as they usually do after they're done. Instead, they now use shovels and brooms to clean up the mess.

Goad also takes pains to say that the lawn at his Lanham-Seabrook house is "just as brown as everybody else's. My flowers are dead."

He hasn't been bringing work home from the office.