The phone rang shortly after 11 a.m. yesterday. A man answered. His sprinklers had been sprinkling away, quite illegally.

"Hi, I'm calling from the Montgomery County Water Conservation Line," came Susan Freiman's chipper voice.

The man's sheepish reply: "I was wondering how long it would take you to call."

A neighbor had turned him in, though Freiman didn't mention that, in the interest of community peace.

"He knew he was being a bad boy just waiting to be caught," Freiman said, recalling the call she made -- and it wasn't the only one.

On the first full day of parched Maryland's first-ever prohibitions on the watering of lawns and the home-washing of cars, some residents got a little, well, rebellious. Or panicky. Or creative. They watered and washed anyway. So others, often their neighbors but sometimes eagle-eyed passing motorists, turned into dime-droppers.

It's a serious business, this illegal use of a temporarily controlled substance, sometimes borne of ignorance, sometimes willfulness. A violation can bring a visit from the police -- and up to six months in jail and a $1,000 fine -- though offenders were merely being politely warned yesterday.

At the Montgomery County Volunteer and Community Service Center, housed in a small office in a seven-story building on Hungerford Drive in Rockville, Andrea Jolly, two of her employees and at least four volunteers became, overnight, the drought hot line and instant water experts.

Workers estimated their four phone lines were jammed with more than 500 calls before they closed at 8 p.m. Jolly said about 20 percent of the people calling 240-777-2600 were neighbors tattling on each other. Most of the other callers just wanted answers.

Q. "May I water my one-acre flower garden?"

A. Not with a sprinkler, you can't. You may use a hose, but you have to hold it.

At the outset yesterday, the questions and neighbor complaints started arriving so fast and furious at the police department's 911 center that the police asked the county to set up the drought hot line.

"We're trying to keep our 911 operators from having to take time to say `Is he holding the hose in his hand or is he running the sprinkler?' " said police spokesman Derek Baliles. "We're trying to enforce the [water restriction] laws, but not at the expense of people in emergency situations."

At the 911 center, dispatchers fielded calls reporting everything from spewing fire hydrants to carwashes pumping away. (Carwashes may operate as long as they use at least 80 percent recycled water.)

"These people are doing their duty," said police dispatcher John Staubb.

Dispatchers took note of the watering violations and faxed the reports to the drought hot line center every 30 minutes. Then volunteers such as Freiman, a Montgomery County public school teacher when she is not a drought recruit, called the alleged violator with a friendly reminder. If the volunteers couldn't reach anyone, police were sent to issue a warning.

Louis Murphy, a hot line volunteer, cupped his hand over a phone's mouthpiece.

"This guy wants to set up a 300- to 500-gallon dunking tank for a family outing," Murphy explained.

"No," Rosemary Clark, a center employee, said.

"Do you consider shrubs a garden?" Murphy asked Clark.

Gardens, see, may be watered with a watering can or hand-held hose.

"Yes," Clark said.

"What about ivy?"

One caller explained a bit too much. She said she was doing her part in the crisis by flushing the toilet only every fifth visit.

It was much the same in St. Mary's County, where the Metropolitan Commission fielded about three dozen calls from neighbors ratting out neighbors.

In Montgomery County, perhaps the day's most interesting question was this: How long is this drought going to last?

Clark's answer: "Until it rains -- long and hard."

Staff writer Jessie Mangaliman also contributed to this report.