A massive water main break has forced the closure of Connecticut Avenue in Washington, D.C., and imposed mandatory water restrictions on Washington Suburban Sanitary Commission customers in two counties.

The break is expected to affect the morning commute, as a hoped-for 6 a.m. reopening of Connecticut Avenue was called off around 5:20 a.m.

Drivers are not able to get between D.C. and the Beltway using Connecticut Avenue, which is closed in both directions between Manor Road and Dunlap Street. That closure will continue indefinitely, WSSC said.

The main broke around 8 p.m. Monday at Chevy Chase Lake Drive, where water gushed several stories high from the 54-inch water main.

The break caused a power line to fall, but no customers have lost power. Natural gas and electric lines run along the water main, so crews from Washington Gas and PEPCO had to secure those lines before work on the water main could begin, said WSSC.

Crews had a scare shortly before 5:20 a.m. when a tree came down at the scene due to the saturated ground.

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The tree brought down some additional power lines, which dashed hopes for a 6 a.m. road opening. Pepco is headed to the scene.

Another tree is also threatening to topple, said WSSC.

Water restrictions in Maryland
While there are no water reported water outages, all WSSC customers in Prince George's and Montgomery counties are required to restrict usage until repairs are complete.

WSSC says all residential and commercial customers must:

Use water only as necessary -- i.e., take shorter showers and turn off faucets after washing hands and while brushing teeth.

Limit flushing toilets (do not flush after every use).

Put off washing clothes if possible.

Limit the use of dishwashers and wash only full loads.

The restrictions could last up to a week, WSSC said. A violation carries a fine of up to $500 fine.

WSSC said in a release it has been working with fire departments from both counties to ensure adequate fire protection.

"Please don't hoard water. We're not running out," said General Manager Jerry N. Johnson. "But if everyone can cut their water use by 10 percent, we should be OK. We appreciate everyone's understanding and cooperation."

Officials said the pipes are old -- circa 1980 -- but did not give a cause for the break.

There is no timeline for repairs, WSSC said.

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