Utilities remain proactive in reinforcing lines against natural disasters
Thanks to comprehensive preparedness by their natural gas utilities, residents of California hit with two earthquakes in early July were able to safely weather the natural disaster.
At Pacific Gas & Electric Company, employees immediately began inspections to bring its Hinkley compressor station back online after the first quake shut it down, Erik Kurtz, a director in PG&E’s Gas Transmission and Distribution Maintenance and Construction organization, told American Gas.
Meanwhile, PG&E’s Leak Survey team was on the ground conducting assessments while PG&E’s Geoscience Team determined areas to survey based on impact models. About 50 miles of transmission line and 49 neighborhood sections or plats of distribution line were inspected, and PG&E’s Gas Pipeline Operations and Maintenance team visually inspected all stations, including compressor and regulator.
The utility also utilized its Picarro leak-detection, vehicle-mounted technology that measures methane in parts per billion and can detect even microscopic leaks. While no leaks were found on transmission pipelines, two large fissures were discovered where the fault crossed two transmission lines, Kurtz said. A day later, a stronger earthquake hit and resulted in another intensive inspection effort. Ultimately, more than 135 leaks were repaired and more than 600 feet of transmission line was replaced.
“With the threat of earthquakes a reality here in California, we train to respond to these types of events, and that training paid off. Safety is our highest responsibility, and that was top of mind for all of us as we worked quickly to assess the damage, make repairs and restore gas service for our customers,” Kurtz said.
Southern California Gas Company took to social media after July’s events to communicate quickly with customers, tweeting a reassuring message that there were no significant impacts to the natural gas system.
“SoCalGas’ natural gas system is extremely resilient during emergencies. It’s designed in such a way that we can respond quickly to isolate or shut off natural gas service to localized areas if needed,” Vanessa Skillman, spokesperson with the office of media and public relations at SoCalGas, told American Gas.
The utility’s pipeline system has many safety controls in place, such as 24-hour, real-time monitoring of transmission pipelines; automatic shut-off valves on portions of its natural gas transmission lines that automatically close when a large pressure drop is detected, immediately stopping the flow of gas; and system operators who can remotely open or close valves from a central control location, Skillman said.
In May, the Pipeline and Hazardous Materials Safety Administration had issued an advisory bulletin to remind owners and operators of natural gas and hazardous liquid pipelines of the potential for damage caused by earth movement, along with their responsibility to protect and patrol natural gas pipelines/facilities and take measures to address consequences of any pipeline failures.