An explosion caused by a Sun Prairie gas leak that hit in the middle of the downtown Tuesday night, killing one firefighter, injuring other first responders and affecting multiple businesses, was complicated by the number of natural gas valve points that feed into the area.
Spokeswoman Cathy Schulze said We Energies was notified at about 6:30 p.m. that a third-party contractor had hit a natural gas line. Shortly after a gas fitter arrived to address the problem at about 7 p.m., the explosion occurred in the 100 block of West Main Street.
“Our workers had to negotiate their way to several different valves at several different locations,” Schulze said. “There were a dozen different valves they had to shut off, so that did take time and obviously, safety was of the utmost concern.”
All 12 gas valves were shut off by approximately 9:30 p.m. Schulze said it has not yet been determined if the explosion occurred in the gas line.
“Our crews were able to stop the flow of gas after safely navigating that scene,” Schulze said. “It was an intricate process that was not as simple as shutting off one valve.”
About 500 customers were left without natural gas service, Schulze said. Crews began connecting customers Wednesday morning.
Schulze said she could not say whether We Energies knew a third party contractor was working in an area or if the contractor alerted We Energies or the Diggers Hotline.
"That is part of the investigation," Schulze said. "We are assessing whether the correct safe digging procedures were followed."
Schulze said anyone doing a digging project is required to call Diggers Hotline at least three days in advance to have their underground facilities marked.
Sun Prairie Police Department Lt. Kevin Konopacki said one firefighter died, a second firefighter remains hospitalized and three others suffered minor injuries, Konopacki said. A police officer and seven civilians also suffered minor injuries.
Konopacki said the Barr House, Glass Nickel Pizza, the Professional Building, Water Tower Chophouse and a residential home experienced significant damage due to the explosion.
The Madison Fire Department’s Heavy Urban Rescue Team is going through the damaged buildings Wednesday to conduct a more extensive secondary search for any possible victims and evaluate structural integrity of the damaged buildings.
“We are confident there is nobody else,” Konopacki said. “We can’t rule that out until they go through.”
People who were evacuated are allowed back into their homes once they have been cleared by a We Energies representative.
The Salvation Army and American Red Cross were assisting with evacuation centers at Sun Prairie High School and Patrick Marsh Middle School. Main Street detours are in effect.