In a muddy landscape, an army of Denver Water workers and contractors pumped, scooped and raced the clock Thursday night in an attempt to reopen Interstate 25 in time for the morning rush hour.
But about 10:30 p.m., Colorado Department of Transportation spokeswoman Stacey Stegman said the massive effort was bogged down.
Chances were “very thin” the interstate would reopen by rush hour this morning — or possibly even by afternoon, she said.
“At best we might be able to get a lane open,” she said. “It’s going very, very slow.”
The northbound lanes erupted with water at the 58th Avenue exit about 3 p.m. Thursday when a 5-foot concrete conduit gave way, spilling more than 2 million gallons and opening a 40-by-40-foot sinkhole 16 feet deep.
“This is a big one,” said Stegman, her voice muted by the growling pumps and the chug and busy beeps of heavy machinery Thursday evening.
The sinkhole was twice the size of one that closed Interstate 70 near Vail for three days in 2003, she said.
When the conduit gave way, no cars hit the hole, but one nearby business suffered water damage. Traffic backed up more than 10 miles, beyond the University Boulevard exit, Thursday evening until CDOT waived tolls and steered traffic onto its two HOV lanes.
Peter Ebrahimi, a software developer from Boulder County, was trying to get home from the Denver Tech Center. After a 45-minute creep, he had made it within 30 yards of the police roadblock.
“Yes, it’s very frustrating, but at least there are no deaths,” he said from his idling SUV. “Everything else, you can live with.”
A flood of heavy traffic poured onto side streets, spreading the jams to surrounding streets.
“That’s Denver — put the water main under your main highway north. Genius,” said Paul Sims, a plumbing contractor from Westminster, as he sat in a traffic jam on Federal Boulevard.
Northbound motorists were advised to take alternative routes this morning, such as Sheridan, Vasquez and Federal boulevards, before they reach I-70.
Ordinarily, the HOV lanes are southbound routes, rather than northbound, during the morning. However, CDOT is prepared to keep them northbound today if necessary.
Brian Good, director of operations and maintenance for Denver Water, said at an evening news conference that the break was caused by overpressurization of the line after a pump failed, triggering an emergency shutoff.
Three electronically activated remote valves immediately began diverting water into other lines and closing down the broken line, a process that took about 15 minutes.
The same transmission pipe broke in 1997 about 100 yards west of the highway, causing flooding and significant damage. Cleanup and repairs took three days.
Since then, Good said, the line has been inspected four times and more than a mile of it has been replaced.
The conduit was installed in 1978. Good said age was not a factor in the break because the line can last up to 100 years.
The pipeline runs from the Moffat Treatment Plant on West 20th Avenue and Kipling Street to a pump station at East 56th Avenue and Quebec Street.
Good said the high-pressure transmission line, which is made of concrete, will be repaired with steel.
No one should lose water service, he said, though water pressure could drop. If there is an outage, customers should call Denver Water at 303-628-6000.
In addition to causing minor water damage to Callcom, 5721 Logan St., the break affected a Qwest phone vault. Denver Water said it was working with Qwest on that issue. A spokeswoman for Qwest did not return calls Thursday night.
Other recent water-main breaks
May 23, 1997: A break in a 66-inch water pipeline turns “Furniture Row” into a raging river as customers and sales people scramble to the roof of the Sofa Mart at West 53rd Place
and Bannock Street. The break caused no damage to nearby Interstate 70.
June 1, 2003: A culvert collapses after a rainstorm, creating a 20-foot-wide sinkhole and closing I-70 in both directions near Vail. The highway is closed for three days, and it takes 11 days to fix the sinkhole.
Oct. 12, 2006: Denver Water worker Shawn Patilla dies when the 6-foot-deep hole he is working in floods at South University Boulevard and East Hampden Avenue. A three-week probe by Denver Water blames the accident on human error by the foreman.
Jan. 14, 2007: Broken main causes a 60-foot geyser at East Alameda Avenue and South Havana Street in Aurora. Water spouts for more than three hours.
Feb. 2, 2007: Extreme cold causes a water-main break at East Exposition Avenue and South Harrison Street. Water flows to South Colorado Boulevard, causing icy driving conditions.
March 14, 2007: A backup of pressure during an inspection causes nearly a dozen lines south of Gunbarrel Road in Boulder to rupture.
Jan. 17, 2008: A water main breaks in the 4500 block of Lincoln Street in Denver’s Globeville section, causing icy driving conditions.
