NEW ORLEANS -- Aging gas pipes are a potential danger everyday in the United States. Back in March, an explosion in East Harlem leveled part of a New York City block. The blast killed eight and injured 48 others.
Closer to home, a 30-inch gas line in Washington Parish, owned by the Florida Gas Transmission Company, erupted in June 2013. It sent flames into the sky.
Fortunately, no one was injured and damage was minimal, but that isn't always the case.
"A natural gas pipeline is a massive safety issue," said Louisiana Public Service Commissioner Eric Skrmetta.
In the last several years, there have been at least six incidents involving damaged gas pipelines. These incidents can cause millions of dollars in damage, injuries and in one case, even death.
Pressurized pipelines criss-cross the country, carrying natural gas between well heads, storage tanks, processing facilities and into our homes. The question is, where does Lousiana rank in this vast above-ground and under-ground network?
"I think if you look at the amount of pipeline in Louisiana, we really do have the most pipelines in the United States," Skrmetta said.
Because Louisiana has so many miles of pipes, it also has a significant amount of older pipelines, and they're not alone. A check of federal safety data shows tens of thousands of miles of pipes in the United State are aging.
Together with our partners at USA Today, Eyewitness News took a look at the infrastructure of one of the area's largest natural gas providers, Entergy New Orleans.
"We've had very, very few events in Louisiana, thank God," said Skrmetta.
Very few events, but the numbers provided to the National Pipeline and Hazardous Materials Safety Administration show Entergy New Orleans is far from perfect. It ranks above the national average in several problematic categories.
The company reports 83.5 hazardous leaks per 1,000 mile of pipe. The national average is just 35.
10 percent of Entergy New Orleans' distribution lines, linking high pressure transmission pipes to low pressure service lines, are made up of 10 percent bare metal. It's a material prone to rust and corrosion. The national average in that category is just 7 percent.
A lot of work was done to Entergy New Orleans' infrastructure after Hurricane Katrina, but it's still old compared to other systems: 65 percent of the pipes were installed before 1970. That's compared to 39 percent nationally.
Michelle Bourg is Entergy's director of gas distribution, and she believes the numbers don't tell the whole story.
"That number, that 65 percent number, does include some pipe that was installed in the 70's, 80's and 90's that we're unable to identify the vintage for. So, it's lumping it together as an unknown," she said.
Bourg said New Orleans is uniquely positioned to replace aging infrastructure. That's because during Hurricane Katrina, corrosive salt water flooded more than half of Entergy's system, totaling about 840 miles of pipe.
Entergy has been aggressively replacing lines in the city since 2007.
"Since then, we've removed almost 50 percent, which is significant. 50 percent of the cast iron pipe from our New Orleans natural gas delivery system," Bourg said.
In many neighborhoods, the company is replacing old, 6-inch cast iron pipes with 3-inch, high-density polyethelene pipe. Entergy is also using directional boring technology, which doesn't dig up streets, sidewalks and yards.
"We're constantly monitoring the condition of our pipe," said Bourg. "We're constantly looking for opportunity to replace pipe where we may have service reliability issues."
But it's expensive work. Just one mile of pipe can cost up to a million dollars to replace. However, Entergy is keeping costs under $500,000 a mile. The company is using insurance money from Katrina and a community development block grant to pay for it.
"We've got a pretty aggressive program in place to implement the right procedures, to make sure we're monitoring the work of our employees and contractors, to make sure we're delivering the most effective results for our customers," said Bourg.
The Lousiana Public Service Commission monitors numerous natural gas systems around the state. Skrmetta said he's confident in the system's overall safety.
"I would say the general consensus is, companies inspect their lines," he said. "They are very good about making sure safety is their number one priority. Generally speaking, it's a safe system and it's demonstrated itself to be safe. obviously, no one knows when the odd event takes place."
That's why Bourg says Entergy New Orleans is working quickly to improve its pipes.
"We've removed pipe at a rate that far exceeds that of the industry average," said Bourg. "So right now, we're on pace to remove about 5 percent of our cast iron per year."