Inspecting our system
Puget Sound Energy's (PSE) natural-gas system has more than 21,000 miles of gas mains and service lines, interconnected across some 2,900 square miles over six counties. In accordance with federal and state law, we regularly inspect all our pipelines for corrosion and defects. Sophisticated electronic gas-detection equipment is employed to inspect every neighborhood's system — block by block, house by house, foot by foot.
Our piping systems with bare steel and transmission pipelines are surveyed for leaks every six months. Our gas mains in service areas with business and high-occupancy structures are surveyed for leaks annually. Plastic natural gas piping and coated steel pipelines are equipped with cathodic protection – a method of inhibiting corrosion on steel pipe. They are surveyed for leaks at least every five years. The cathodic-protection systems are inspected anywhere from every two months to every ten years, depending on their type.
Moreover, PSE technicians and other field employees monitor the gas system daily for anything out of the ordinary, including construction activity in the vicinity of gas lines.