Your correct, this does not sound right to have a gas leak to travel that much of distance. High pressure mains are not usually set in residential neighborhoods. What normally happens, if the main drop pressure suddenly there are protections, when a major pressure drop in the line the station sensors would automatically shut down the fuel immediately. The only other time that something like this happened was in San Bruno CA.. I'm looking at this from the perspective of some one who work many years in the LNG and propane industry.


San Bruno pipeline explosion

The San Bruno pipeline explosion occurred at 6:11 pm PDT on September 9, 2010, in San Bruno, California, a suburb of San Francisco, when a 30-inch (76 cm) diameter steel natural gas pipeline owned by Pacific Gas & Electric exploded into flames in the Crestmoor residential neighborhood 2 mi (3.2 km) west of San Francisco

International Airport near Skyline Boulevard and San Bruno Avenue. The loud roar and shaking led some residents of the area, first responders, and news media to initially believe that it was an earthquake or that a large jetliner had crashed. It took crews nearly an hour to determine it was a gas pipeline explosion. As of September 29, 2010, the death toll was eight people. The United States Geological Survey registered the explosion and resulting shock wave as a magnitude 1.1 earthquake. Eyewitnesses reported the initial blast "had a wall of fire more than 1,000 feet high".

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