No fatalities yet, but local gas line strikes spike

Public, private crews at fault; state fines city seven times in 2003

Public and private construction crews appear to be hitting more buried natural gas lines under Minneapolis streets, and the city is trying to reduce the number -- and the chance of a potentially fatal explosion.

In 2003, public and private construction crews hit 63 gas lines during various projects, an average of more than one a week, said Interim Fire Chief Bonnie Bleskacheck. By July 15 of this year, crews had struck 41 gas lines.

The Minnesota Office of Pipeline Safety fined the city 10 times in 2003, seven times for hitting gas lines (see sidebar), three times for hitting fiber optic and telephone lines. Each time, the city paid the maximum $1,000 fine, according to state records.

According to Fire Department and Public Works data, the city isn't even the prime offender; private crews accounted for more than half of 2003's hits.

Minneapolis has not had a fatal gas line hit, as had happened in St. Cloud. She said, "We have been very, very fortunate."

On Dec. 11, 1998, a cable company struck and ruptured a 1-inch-diameter underground gas pipe in St. Cloud, according to a U.S. Department of Labor report. A half-hour later, an explosion killed four people, seriously injured another person and destroyed six buildings.

In Minneapolis, public or private crews have damaged gas pipes as large as 16 inches in diameter.

The Office of Pipeline Safety has not issued any fines in 2004; one incident involving city crews is under investigation, a state official said.

A growing danger?

At first glance, it appears Minneapolis's 10 fines in 2003 represent a significant spike.

From 1996 to 2002, the Office of Pipeline Safety did not fine Minneapolis once for hitting gas lines. It issued three written warnings and three verbal warnings during the seven-year period, on average less than one a year, according to state data.

Mike Kennedy, Public Works' emergency response point person, said he did not know why the number of fines had increased. Part of the answer could be that the city had a few incidents and they triggered more state scrutiny, he said.

In 2003, "we had a couple of projects where we did have some problems," he said. "That brought us more into focus and [to the] attention of the office, so they began to see more."

City Councilmember Gary Schiff (9th Ward) raised concerns after Public Works crews repeatedly struck natural gas lines during the 2003 reconstruction of East 38th Street, triggering evacuations.

James Dykes, Public Works safety manager, said increasing work volumes also raised the risk of gas line hits. He called 2003 a peak year for excavations and other work that created potential gas line damage.

Mismarked gas lines are another cause. Kennedy said many city roads are 40 to 50 years old. Downtown streets in particular are dense with buried utilities: gas, telephone, electric, sewer and water, and maybe fiber optic cables. Utilities use the best records and information and techniques they have to locate buried lines, he said.

"When you get stuff this old and this dense, mismarks can happen," Kennedy said. "It is not to blame anybody. It is just the fact of life."

Bleskacheck said she has gone to sites where the gas line location was 10 feet off from where a map indicated it. "You could see they were digging right where they should have been and the gas line shouldn't have been there -- and it was," she said.

Kennedy said the gas lines get marked on the street before work starts. Crews typically hit the service lines, the smaller pipes branching off the main line to individual homes and businesses. They are not as well documented, he said.

Sometimes, the service lines are extremely shallow and sometimes they are encased in concrete, making gas line hits more difficult to avoid, he said.

Crews do hit gas mains, however. They tend to be the more serious incidents that draw the Office of Pipeline Safety's attention.

The Office of Pipeline Safety does not track all gas line damage city-by-city; it only gets involved with significant events, said Administrator Charles Kenow.

Statewide, the number of hits on buried gas and electric lines is dropping, Kenow said. In 1996, the state reported 6.2 hits per 1,000 requests to locate lines; in 2003 the number was 2.6 per 1,000 requests.

Bleskacheck said she thought the city could reduce the number of gas line strikes but not eliminate them.

In the event of a hit, Bleskacheck said she wanted to make sure both Fire and Public Works crews worked together to maintain safety.

"I want to work with the construction crews on-site," she said. "If something like this should happen, they need to deny entry into the area until we get there -- so we don't have a pedestrian walking by smoking a cigarette."

Reducing Minneapolis gas line damage is a high priority, Kennedy said. The Office of Pipeline Safety has done multiple trainings for Public Works staff.

Public Works crews have had mock digs, Kennedy said. Trainers bury a pipe and have operators practice digging around them, "so they can get used to the finesse," he said.

The Public Works and Fire departments are collaborating to better track mismarking and operator error, Bleskacheck said. The Fire Department is collecting more data for each incident, such as whether city or private crews hit the gas line, she said.

Private crews account for a good share of Minneapolis's gas line damage, Kennedy said. When the city rebuilds a road, utility crews also repair their underground lines and cables, he said. Public Works crews hit gas lines 26 times in 2003 -- or less than half the 63 total hits reported by the Fire Department.