Katherine Shaver/The Washington Post – WSSC crews work to repair a broken water main at Connecticut Avenue and Chevy Chase Lake Drive in Md. Pepco crews also work to repair power lines that came down when a tree pummeled by the geyser fell about 5 a.m. Tuesday.

Two lanes of northbound Connecticut Avenue are likely to remain closed in Chevy Chase through the Wednesday afternoon rush to allow for repairs on a major water main break, a utility official said Wednesday morning.

The three northbound lanes will narrow to one lane north of East-West Highway, near Chevy Chase Lake Drive. All three northbound lanes will reopen before Jones Bridge Road. The area is just inside the Capital Beltway. Southbound lanes remain open.

The same lane closures Tuesday evening snarled traffic throughout southern Montgomery County, as side roads clogged with motorists seeking alternate routes.

Keeping two northbound lanes closed provides a safe area for utility repair crews to park trucks and use heavy equipment, said Kira Calm Lewis, a spokeswoman for the Washington Suburban Sanitary Commission. Crews are scheduled to remove and replace the broken section of water main on Wednesday, she said. Pepco and Washington Gas workers are also in the area repairing damage to their lines, Lewis said.

The water main, which is five feet in diameter, exploded Monday around 8 p.m., sending up a 40-foot geyser of rocketing water. The geyser, which took about seven hours to turn off, resulted in the water distribution system for Montgomery and Prince George’s counties losing more than 60 million gallons, WSSC officials said.

WSSC has ordered 1.8 million people in both counties to cut back on water use by taking shorter showers, limiting toilet flushing and running only full loads in dishwashers and laundry machines. Violations of the water restrictions carry up to a $500 fine.