NORFOLK - There's a hidden danger lurking underneath thousands of miles of ground in neighborhoods across the country. Old pipes, made of obsolete materials like cast iron and bare steel, are carrying natural gas into millions of homes including some here in Hampton Roads.
A joint USA TODAY/13News Now investigation has uncovered hundreds of miles of the outdated pipe in our area.
USA TODAY Investigation: Look out below: Danger lurks underground from aging gas pipes
The pipe can pose a danger when the bare metal --steel or cast iron-- becomes brittle and corrodes away or cracks under the weight of constantly-shifting soil.
Cast iron pipe has been blamed for deadly explosions across the country, including explosions at a home in Seattle in 2004 and another at a home in Austin, Texas in 2012.
Most recently, a leaking cast iron pipe has been identified as the preliminary culprit behind an explosion in March that leveled an entire apartment building in Harlem.
"It's known that it gets old and brittle and leaks and causes tragedies like we saw in New York City this past year," said Carl Weimer, the executive director of the National Pipeline Safety Trust.
Weimer and other experts say that aging cast iron and bare steel pipe can become dangerous because it corrodes or can crack under the weight of shifting soil. Either scenario leads to dangerous gas leaks.
With the number of incidents related to faulty pipes on the rise, Weimer hopes regulators and gas companies will take steps to prevent future disasters.
"I think there are a whole bunch of things that need to be done," he said. "Some of the pipeline safety regulations need to be tightened. Some of the older pipeline need to be removed and replaced out of the ground.
There are two natural gas providers that serve Hampton Roads: Virginia Natural Gas serves the majority of the area and Columbia Gas of Virginia serves portions of Portsmouth, Chesapeake, Suffolk and all of Isle of Wight County.
Virginia Natural Gas operates 34 miles of cast iron pipe and more than 300 miles of bare steel. The total cast iron and bare steel pipe accounts for 6.6 percent of VNG's total pipeline.
Columbia Gas operates just under thee miles of cast iron pipe and nearly 200 miles of bare steel pipe, totaling 4.1 percent of its pipeline across the commonwealth.
The national average for cast iron and bare steel pipe is seven percent, more than either local company's average.
Spokesmen for both companies say they have been replacing the pipe for years.
"Columbia has been very proactive, actually, going back to the mid-90s replacing and upgrading our facilities," spokesman Robert Innes said.
Innes said that the company hopes to replace its remaining three miles of cast iron pipe by the end of next year. He did not give a timetable for replacing the remaining 200 miles of bare steel pipe but said the company has plans to continue replacing that pipe, too.
"We see it as some infrastructure that's aging and we're actually working right now o get it out of the system," Duvall explained.Robert Duvall, president of Virginia Natural Gas, said his company will have all of its cast iron and bare steel pipe replaced within the next five years.
Both Duvall and Innes said that they deploy an army of inspectors to monitor aging pipelines that are still in the ground until they can be replaced.
Replacing dangerous pipe comes at a big cost. Companies typically pay between $1 million and $3 million to replace one mile of pipe.
Innes, the Columbia Gas spokesman, said it's a worthwhile cost.
"There's a cost to put it in the ground. There's a cost to retire it. But it's very beneficial to public safety, which is our number one priority," Innes said.
However, the hundreds of millions of dollars to ensure customer safety is being passed on to rate payers.
In order to increase rates, gas companies have to make their case before the Virginia State Corporation Commission.
Virginia Natural Gas won a rate case in 2011. It was the company's first increase since 1996. Listed among the main reasons for the increase, though, was the company's ongoing projects to replace aging pipeline.
"Over the last five years, VNG has invested $33.1 million in pipeline replacement and has a plan to continue with significant additional efforts to replace aging infrastructure over the next several years," the company's application read.
Columbia Gas filed a rate case in April 2014. The case is not finished yet but the company won approval to increase customers' rates on an interim bases effective Monday, September 29.
The average bill will increase by roughly $7.
Columbia Gas' application rests heavily on its efforts to replace aging pipeline as the need for an increase.
Columbia spokesman Robert Innes said the increase was necessary to pay for the replacement project.
"Why can't you do that, you know, at no extra cost to your customers," 13News Now asked. "Just as in any business, there is a cost to improve your system."
Innes said his company is subject to many regulations that make it different than other businesses. He said it is fair to make customers pay a higher price to stay safe.
"We believe it is," he said. "You know, the safety of the general public and the safety of our customers [is our top priority]."