Attention Friday turned to tallying up the cost and damage from a massive water line break that sent 14 million gallons of water into the streets near downtown Minneapolis, shutting down businesses and flooding streets.

The city assured residents and businesses affected by Thursday's break that drinking water is safe, but is testing it as a precaution. A handful of businesses could be without water until late Sunday, but they're hoping to restore traffic on at least some lanes of Hennepin Avenue by rush hour Friday. 

A backhoe working at a construction site on the west side of the Hennepin Avenue Bridge broke the line Thursday afternoon, shutting off water to a wide swath of the city. Crews have been working around the clock since to assess the damage, clean up and begin repairs.

The backhoe that tipped after rushing water undermined nearby soil was plucked from the hole Friday morning while representatives from utilities kept watch over the stability of their pipes.  But the collapse of a portion of S. 2nd St. has kept the damaged portion of pipe covered.

"It's buried under a lot of debris and dirt," said Scott Beron, public safety director for Ryan Companies, the contractor for the development. 

City Engineer Steve Kotke said once the pipe is uncovered, workers will assess damage and plan to install a sleeve over the damaged section.  He said he thinks service can be restored by Sunday night to about half a dozen customers along three blocks of 2nd that don't have water.

Initial checks of the area by city street workers found no significant damage to nearby streets, although they haven't been able to inspect the area right around the crater to see if it is compromised.

Kotke said the city has no idea how much damage the rupture caused. "We're going to be investigating that," he said.  "We don't even have a ballpark right now."

Drinking water deemed safe

The city continued to assure water customers who lost and regained service Thursday that their water is safe.  Glen Cerads, assistant director of the city's water utility, said that the water system was able to maintain sufficient pressure to keep water moving toward the break, rather than experiencing backflow that might contaminate the broader water supply.

For reassurance, the city will test water from about 20 locations within a several-block radius of the leak.  Tests will be run for bacterial infection, as well as for toxins like pesticides and metals. Some test results will be available Friday, while others won't have results until the weekend.  The city will chlorinate the three-block stretch of water pipe closest to the break to disinfect it once it is repaired.

Courts likely to sort out blame

Meanwhile, a new picture emerged Friday of what happened just before the break: A Ryan subcontractor was trying to install a construction caisson under the water pipe so that the complex that Ryan is building could be connected to the sewer system.  That subcontractor,  United Water and Sewer of Brooklyn Park, hasn't returned Star Tribune calls.

"The biggest concern right now is to get water back on," Cerads said.  "Why it happened is going to be secondary to getting it fixed."

Kotke said that the courts will probably  sort out  blame for the accident after the city sums the damage.  It has calculated the cost of water lost to the break at $65,000.  It also incurred expense calling out crews to deal with the flooding and reroute traffic, beyond whatever repairs the pipe needs.

Marie Asgian, the city's water distribution supervisor, said the cost of the city's response to the break, clean-up and loss of water has not been estimated yet. The lost water represents about one third or more of the city's daily water production during winter months, Asgian said.  It's also apparently without recent precedent. 

"I spoke with a person who's been here 30 years and he said this was the biggest one we've ever seen," she said.  "It was a big chunk of the pipe that must have been taken."

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

Dozens of cars under water

Near the break site, 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 Thursday.

Pete Nowacki, spokesman for the postal service, said the back ramp of the massive building remained closed Friday because the bottom level was under water.

Up to 30 postal vehicles and an "undetermined number" of employee vehicles are there. Earlier, an official estimated 20 employee vehicles were affected.

"There's substantial water down there. Those cars are going to losses," Nowacki said. The ramp is not usable but the office has a second ramp for employees.

"We're open for business; we're processing mail as usual," he said.

Asked if employees were drinking the water, he said yes. "It was certified by the city as potable. We got water to drink and a post office that works. I can't ask for more. And we got sunshine," he said.  

Toilets flushing, water clear

Many downtown workers were sent home early Thursday because water was brown and toilets weren't working.

Toilets were flushing and water ran clear Friday morning at the Fifth Street Towers in downtown. The buildings and Caribou Coffee shut down early Thursday because of the break. "We got through it," Caribou staffer Luke Norfleet said.

When Louis Ahlberg opened the New-Mart at 6 a.m. in the TriTech Office Center at a. 4th St. And 3rd Av. S., the first thing he did was restock the empty water shelves in the cooler. "It's rare to have to put that much in," he said. "I was just shaking my head. I couldn't believe it."

Ahlberg said he restocked with 24 20-ounce bottles as well as a few liter bottles. But on Friday he said water sale were back to a trickle and water was back to normal in the building after the total loss of liquid Thursday.

He said business seemed slower, however, and he speculates that lots of workers stayed home just in case.

Robert Ramirez of St. Paul, who works for a trading company at Marquette Plaza in downtown, said he was hesitant to drink the water Friday.

"Even with a water filter, I don't think I will. I will probably drink bottled water today," he said as he walked to work.

Roads opening

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

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

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

Break disrupted nightlife

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.

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."

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