OXON HILL, Md. — Thousands of people have been stocking up on bottled water as utility officials in Maryland's Prince George's County, just outside Washington, prepare to repair a failing water main. The repair means residents could spend several days under water restrictions as temperatures soar into the 90s. Here's a look at how it's affecting communities, and what officials are doing to prepare.

HOW MANY PEOPLE WILL BE AFFECTED?

About 200,000 to 300,000 of the county's more than 850,000 residents are under a mandatory water restriction. The affected area includes Joint Base Andrews, home of the president's Air Force One.

WHAT DO THE RESTRICTIONS MEAN?

Residents are being asked to use water only when necessary. They're being asked to take short showers, turn off faucets after washing hands, limit flushing toilets, and postpone using washing machines and dishwashers. Residents are also being told not to water lawns or wash cars.

WHY IS IT HAPPENING?

The Washington Suburban Sanitary Commission is replacing a section of a 54-inch pipeline after alerts from a warning system showed that it appears to be failing.

HOW LONG WILL IT TAKE?

The sanitary commission says the repairs could take three to five days.

HOW ARE PEOPLE PREPARING?

Officials urged residents to stock up on water before water was shut off Tuesday night and water is being provided at three schools in affected areas. Officials are also opening reception centers where people can shower, use the bathroom and get bottled water at two other schools. The county fire department is prepositioning water tankers in the affected area.