So far this year, local police and SCE&G crews have responded to at least 60 gas line breaks across the Charleston area.
It’s a pace that could lead to a record number of disruptions in 2012 compared to recent years, but such problems aren’t unusual.
Since 2009, Charleston has experienced about 200 natural gas line incidents a year, according to SCE&G figures.
No one has been hurt, but they have led to traffic snarls, street closures — even police warning calls to nearby homes.
In January, an underground gas line ruptured near East Bay and Tradd streets. Parts of seven streets were closed off for hours, and more than 400 homes, restaurants and other businesses went without natural gas service overnight.
That same month, a separate leak closed down R.B. Stall High School for a day.
Last month, two different sections of Meeting Street — one near George Street and another near Tradd Street — were closed for a few hours because of gas leaks. In June 2010, two gas leaks about a week apart shut down an area near Wentworth and King streets for a few hours each time.
The vast majority of these incidents stem from contractors and others digging into buildings or under streets and sidewalks without knowing what’s buried beneath, SCE&G spokeswoman Kim Evertt Asbill said.
She said it’s important that anyone digging call 811 at least three working days beforehand so the location of utility lines can be marked.
The special phone number was created in 2007, and while there are still more than 100 incidents of gas line leaks and ruptures each year, public education appears to be paying off.
“In the past five years, we’ve seen more than a 50 percent reduction in the number of incidents on our system that can be attributed to a failure to call 811,” she said. “There is no doubt that calling 811 before you dig can make a tremendous difference.”
State regulators also spend a lot of their time trying to minimize third-party damage, said Carey Stites, gas manager with the state’s Office of Regulatory Staff.
“There are no guarantees in this business, but I have to take our hats off to our operators and brag a little bit,” she said.
SCE&G first installed cast iron gas pipes in Charleston during the late 19th century, when it burned coal to manufacture gas for street lights, Stites said. The utility switched over to natural gas around 1954, then it gradually replaced the cast iron pipes with less brittle ones.
By 1983, all of Charleston’s cast iron pipes had been replaced. Columbia’s was changed out by 1991, Stites said.
An 83-year-old cast iron gas main is suspected of being the cause of a February 2011 explosion that killed five people and damaged 47 homes in Allentown, Pa.
There haven’t been any serious injuries from recent gas leaks in the Lowcountry.
Charleston Fire Department Capt. Greg Chesher, the city’s HAZMAT operations officer, said the city’s first job is to determine the size of a gas leak and how many trucks should respond. For the larger leaks, the department also figures out how large an area should be cleared of anything that could ignite a gas cloud, such as smokers, vehicles, pilot lights and open stoves.
Charleston police Lt. Jason Emanuele, special units commander, works with the fire department to close off streets, as needed. Police can even use reverse 911 to notify nearby homeowners of street closures and advise them to avoid certain areas.
Emanuele said police work with fire officials to reopen streets as soon as possible.