MOHAVE COUNTY, AZ — Southwest Gas officials are publicly acknowledging that they are seeing enough deterioration on some active Driscopipe 8000 lines in Arizona to replace entire neighborhoods worth trying to head off future leaks.
Southwest Gas operates 10,000 miles of Driscopipe 8000, which the manufacturer has warned can become brittle and crack under certain circumstances in desert climates.
Southwest Gas executives previously said they could eliminate the danger by replacing a small subset of “inactive services” and “stub” pipes. However, during a trip to Mohave County this month, the ABC15 Investigators uncovered the company was also quietly replacing miles of active Driscopipe 8000 lines.
In Mohave County, Bullhead City and neighboring towns along the Colorado River are some of the state’s hottest places. They are also places with the highest concentration of past Driscopipe 8000 premature degradation leaks, according to ABC15’s analysis of Southwest Gas reports to state utility regulators.
Locations in the map below are approximated from a geolocation service.
The ABC15 Investigators mapped more than 140 locations of past Driscopipe 8000 degradation leaks that occurred since 1999 in Arizona. Most of the pipe failures were detected by mobile leak patrols. Some of the leaks led to explosions, fires, or evacuations. All leaks were repaired.
“I didn't know about it until you said something,” said Jessica Willson who lives in the Sunrise Vistas neighborhood in Fort Mohave. There were three failures in Driscopipe 8000 lines in the area from 2013 to 2015, according to Southwest Gas. ABC15 identified several of these leak cluster neighborhoods in Arizona.
“When you go around the curve, they had a gas leak because you could smell it,” Willson remembered. “Somebody finally reported it.” That leak was fixed.
Southwest Gas sent crews to Sunrise Vistas again in 2016 for a major project. Neighbors remembered how the crews removed and replaced the active service lines to their homes and the mains along the street.
“Once they tore it up, we couldn't leave the house or anything,” Willson said.
Willson remembered the project because it was inconvenient, but it's also significant because the company was replacing “active” service lines and mains, which were distributing natural gas to homes and businesses.
That's a departure from Southwest Gas’ past public statements about the circumstances in which Driscopipe 8000 lines were at risk for leaks.
The company's website said premature degradation may occur only when several conditions were involved including the pipe had gas inside, but it was not flowing. The company’s examples included “inactive services” that have been disconnected from a customer for years or a “stub” pipe never extended to a customer.
“These are really a very small part of the [Driscopipe] M-8000 that we have,” said Southwest Gas’s then-CEO John Hester during a September hearing before the Arizona Corporation Commission.
During that hearing, company officials also told the Arizona Corporation Commission that getting rid of all the inactive services and stubs in the hotter parts of the state will all but eliminate the risk of leaks and explosions.
“It should be, in my mind, essentially zero,” Hester said in September.
When Southwest Gas officials met with ABC15 last week, Kevin Lang, the company's director of engineering services, confirmed some active lines distributing gas to homes and businesses are also deteriorating.
“We've trained all of our field personnel and contractors to recognize what external degradation and internal degradation look like,” Lang said. “When it's seen in the field, we have processes and procedures to cut out a sample of pipe and send it into our lab.”
If the lab finds external degradation that's at least 10% of the pipe wall's thickness or any amount of internal degradation, Lang said, “We are proactively replacing them in the event that they could cause leakage in the future.”
Lang said Southwest Gas has not found any active lines that have deteriorated to the point of a leak.
The company has not said exactly where and how much active Driscopipe 8000 line the company has replaced in Arizona, but the company is reporting what's being replaced and why it's being replaced in Nevada to utility regulators in that state.
ABC15 sent one of the Nevada reports to Arizona Corporation Commissioner Anna Tovar.
“We'll continue to hold the company accountable,” Tovar said.
Last week, she sent a letter asking Southwest Gas to provide "quarterly updates on all Driscopipe 7000 and 8000 leaks and replacements in your Arizona service territory."
The letter also asked the company to “identify any individual projects in the same geographic area that required both main and service line repair or replacement."
“I'm always more to advocate to be proactive instead of reactive, especially in this situation,” Tovar told ABC15 Investigator Melissa Blasius. “This could potentially be, as you said, a life-or-death situation.”
The first quarterly report is due June 15, and a Southwest Gas official said it will formalize the same kind of information that is already shared in discussions with the state's pipeline safety office.
In Sunrise Vistas, resident Jessica Willson said she's not surprised Southwest Gas did not fully divulge to neighbors like her why the pipes in her neighborhood had to go. She was also relieved to know she has newer, safer gas lines now.
“Very good thing; this is a good neighborhood,” Willson said.
Southwest Gas officials told ABC15 their risk assessment algorithms prioritize leak cluster neighborhoods like Sunrise Vistas for accelerated monitoring and possible pipe replacement.