Southwest Gas is now explaining how often a problematic type of natural gas pipeline is leaking in a report submitted to state regulators.
The report to the Arizona Corporation Commission on Driscopipe 8000 was docketed last week after a hearing about a natural gas explosion that injured four men in a Chandler strip mall a month ago.
Southwest Gas has known for years that Driscopipe 8000 can prematurely degrade in the desert heat, especially in smaller diameter dead-end lines - stubs - that contain gas that's not actively flowing. A Driscopipe 8000 line, which was misidentified on Southwest Gas maps, leaked leading to the Chandler explosion.
In its filing, the company said it removed or abandoned nearly 63,000 of the inactive stubs and service lines in Arizona since 2014. About 22,000 these inactive sections still exist in Arizona, but Southwest Gas executives plan to remove the pipes or close them off by 2023.
According to the report, there have been 89 leaks from the deteriorating Driscopipe 8000 lines since 2014 in Arizona. On average, that's about one leak a month somewhere in the state, but the company says the data also shows 99.6% of the lines have not leaked.
Utility industry watchdog Stacey Champion said the leaks are not as rare as the company statistic makes them out to be.
"I think we definitely need better oversight on a more regular basis," Champion said. "People need to ask more questions and then it really comes back to those large utilities be held accountable"
Four men were injured in last month's explosion. Printshop owners, Andrew and Dillon Ryan, are now recuperating at home. Glenn Jordan had surgery Saturday and is still hospitalized, according to his wife. The family of the fourth survivor, Parker Milldebrandt, said they are grateful for the medical care and community support he's receiving.