minneapolis

An area near the Hennepin Avenue Bridge remained closed Friday morning after a major water main break in downtown Minneapolis flooded streets and cut off water to a substantial swath of the city just before rush hour Thursday afternoon.

Crews worked through the night to repair the damage caused by 14 million gallons of rushing water.

The Hennepin Avenue Bridge was opened overnight, but parts of Hennepin Avenue and nearby stretches of 1st and 2nd Streets N. will remain closed through the morning rush hour, officials said.

Also, numerous Metro Transit bus routes remain disrupted Friday morning. They include routes 4, 6, 6U, 7, 10, 11, 12, 25, 61, 141, 667, 668, 671, 672, 673 and 674.

"We want to make sure the rushing water didn't undermine the pavement or utilities below the roadway," said Public Works Director Steve Kotke.

The Hiawatha light-rail line is operating normally, the transit agency said.

Rush-hour traffic on Central Avenue approaching downtown from the north was heavier than normal, with Hennepin Avenue closed. Motorists were turning to the 3rd Avenue Bridge as an option for crossing the Mississippi River.

About a half-dozen buildings in a three-block area along 2nd Street N. from 3rd Avenue N. to Hennepin Avenue are likely to be without water until Saturday evening while crews make repairs and disinfect the water main, Kotke said.

All of Hennepin County's downtown buildings will be open Friday, a spokeswoman said Friday morning. That includes the Central Library not far from where the main break occurred.

The break occurred about 2:30 p.m. Thursday, forcing workers in businesses left without plumbing to head home early, snarling traffic and disrupting nightlife. The break was under 2nd Street N. at Hennepin, where a $70 million retail-apartment complex is under construction.

The project, called 222 Hennepin, will be a 580,000-square-foot mixed-use development that will contain 286 luxury apartments and be anchored by a Whole Foods Market. Work began in February and is expected to finish this summer.

Scott Beron, public safety director for the developer, Ryan Companies, said a subcontractor, United Sewer and Water, was boring under the street to hook up city utilities to the project when the break occurred. The crawler hoe that might have punctured the main fell onto its side as water gushed out and undermined the soil beneath it.

Before dawn Friday, a crane was positioned to pull the hoe from the scene.

City Attorney Susan Segal said Minneapolis will seek reimbursement from the party responsible for cleanup costs and other damages.

The 36-inch pipe was "a main transmission line for the southern half of the city," Kotke said. Residents as far south as Lake of the Isles to the south and west were affected when pressure dropped.

By the time workers shut off the water an hour and 20 minutes after it began to flow, nearby sidewalks were glazed in ice. As the water slowly ebbed, backhoes scraped layers of mud left behind while others covered the street in salt to break up the fast-forming ice and keep sewers open.

The Mill City Museum closed at midafternoon, and the Guthrie Theater canceled Thursday night's performance of "A Servant of Two Masters."

The U.S. Postal Service Building sustained the most damage of any building. The intercom at the post office warned employees they wouldn't be able to get to their cars in the underground ramp. One official estimated that 20 employee cars were partly submerged, as well as roughly 30 postal vehicles.

At Hennepin County Medical Center on the other side of downtown, surgeries and other operations remained on schedule thanks to a backup system, a spokeswoman said.

sbrandt@startribune.com • 612-673-4438

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