When the Guardian initially phoned the Planning Department to ask about digging near pipelines, the phone call was returned by the Department of Public Works. Anytime a street excavation project is planned, DPW's Gloria Chan explained, a notice of intent is issued 120 days beforehand to PG&E, AT&T, the Public Utilities Commission, and any other stakeholders that might have something running underground. Projects are then designed to integrate existing lines. "Sometimes the information we get may be 40 years old," Chan said. Through a mandated process called USA Service Alert, people go out to physically mark where the underground infrastructure begins and ends on the project site before a contractor starts breaking ground.
That same process occurs with private development projects, explained Alan Kropp, a geotechnical engineer with the firm Alan Kropp & Associates. Kropp said it's left up to a private contractor to work out the technical details for digging, which are governed by a set of regulations. "If you're one foot away or three feet away, most pipes don't care," Kropp said, but he acknowledged that if a pipe is deteriorated, there could be instances where digging a normally safe distance away could still pose a problem.
"Almost all the time, the system works well," Kropp said. As for the condition of the pipe, Kropp said, that information generally doesn't guide project decisions. "It's really up to the owner of the pipeline," he said. "They would be the ones in control of that information."