DERWOOD, Md. -- Montgomery County is closing all restaurants that are customers of the Washington Suburban Sanitation Commission in the areas affected by a major water main break, News4's Darcy Spencer reported.

The affected area is northern Montgomery County outside of the Beltway with the exception of Poolesville and Rockville. About 1,200 food service facilities, including fast-food restaurants, are being closed.

Water service has been restored and mandatory water restrictions are lifted in Montgomery County, but a boil advisory is still in place. The WSSC reported that service was back to normal throughout the county about 9 p.m. Monday.

The boil advisory will remain in effect for three days, WSSC said.

Patrick Lacefield, a spokesman for the county, said Monday night that the order to close foodservice facilities outside the Beltway came in consultation with the state Department of Health. The only exception was food sold in original, sealed packages and fresh fruits and vegetables not washed or misted at the foodservice facilities.

He said although the broken main had been repaired, the closures were ordered by Montgomery County Executive Isiah Leggett because of "overriding health concerns."

100 Million Gallons Lost After Water Main Ruptures

A 48-inch pipe ruptured Sunday just after 9 p.m. near Rockville Regional Park at Muncaster Mill Road and Meadowside Lane, sending 100 million of gallons of water pouring into nearby Rock Creek.

Jim Nuestadt, a spokesman for the commission, said a large number of people were affected, but he didn't have a specific number.

"People were feeling it all over Montgomery County," he said.

Nuestadt said a drop in water pressure was first noticed Sunday night, but the break wasn't pinpointed until Monday morning in a wooded area of the park. Initially, authorities thought the break was in a 36-inch water main that runs parallel to the broken pipe, which was 38 years old.

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"Right now, we believe the pipe failed," said Lyn Riggins, commission spokeswoman. "It's a pre-stressed, concrete pipe, and inside the pipe is wire. When that wire gives way, the pipe cannot stand the pressure of the water, and it gives way. We believe that's what happened. It's still too early to say an exact cause."

Because of the delay, storage tanks that keep water pressure up were emptied, causing the wide-ranging drop in service. The utility closed valves and took other measures to restore pressure. The Montgomery County Emergency Operations Center worked through the night.

Consumers who experienced very low water pressure or little water face a heightened risk of contamination, the utility said.

Residents of the Shady Grove, Germantown, Olney, Hampshire Green and Burtonsville areas are advised to boil water as a precaution. There is no indication the water system has been contaminated, officials said.

Water should be brought to a rolling boil for one minute before using. Boiled or bottled water should be used for drinking, making ice, washing dishes, brushing teeth, and food preparation.

Residents who receive their water from the city of Rockville and from Poolesville are not affected by the restrictions or boil advisories.

The major break also caused smaller pipes, such as one at Muncaster Mill and Redland roads, to rupture, sending water bubbling up onto roads. Traffic was disrupted Monday morning while crews repaired the leak. About 80 customers were affected.

Residents, Businesses Get By Without Service

Some residents didn't have water, and others reported dirty water flowing through their pipes.

Sylvia Rinaldi said she brushed her teeth, made coffee and ate a bowl of cereal before she realized there might be problems with the water.

"What can happen? I'm going to get diarrhea? So, I get diarrhea," she said.

At Montgomery County General Hospital, tanker trucks with water were called in to provide water for the cooling system, fire sprinklers and other essential functions, said hospital spokeswoman Lynn Myers.

Myers said patients can still use hospital toilets. She said the surgery schedule hasn't been disrupted too much, but a couple of surgeries were rescheduled because they require a lot of water.

At Shady Grove Adventist Hospital in Rockville, patients and staff were given bottled water because of the water advisory. At Casey House, a hospice, some people dropped off bottled water donations.

Meanwhile, county health officials contacted restaurants and food service companies in affected areas to advise them not to serve prepared food if they have no water service. The county did not issue an order requiring them to shut down, said county spokeswoman Mary Anderson, although many decided to close for the day.

Robert Wu said he couldn't afford to close Spring Garden Chinese Restaurant. He said he stored up water and boiled it, one bucket at a time.

Montgomery County government facilities within the Wheaton, Glenmont, Olney, Burtonsville, Gaithersburg and Germantown areas were closed Monday.

Montgomery County Public Schools facilities without water were closed. Only emergency personnel were permitted in the buildings. All Montgomery County summer camps also were closed.

Evening Activities Cancelled At Schools

Community activities are cancelled at: Barnsley ES, Belmont ES, Brooke Grove ES, Cloverly ES, Damascus HS, Drew ES, Edison Center, Farquhar MS, Flower Valley ES, Georgian Forest ES, Greenwood ES, Kennedy HS, Magruder HS, Mark Twain, Olney ES, Redland MS, Rosa Parks MS, Sherwood ES, Sherwood HS, Shriver ES, Smith Center, Stonegate ES, Weller Road ES, Wheaton HS and Wheaton Woods ES.