Never mind if it's ontime or being properly managed, are Muni tunnels safe? The San Francisco Examiner contends that outside engineers question the viability of several tunnels, pointing out that they have not been inspected for earthquake safety.
While the Sunset and Twin Peaks tunnels were found to be "in good serviceable condition," many must-do repairs were reported.
The Examiner reported:
Asked if the tunnels’ vulnerability to earthquakes had ever been studied, [SFMTA spokesman Paul] Rose said no.
“Our maintenance inspections have assured us the tunnels are in good, serviceable condition,” he said, adding that the known defects “do not jeopardize the safety of our riders.”
Repairs, according to an internal SFMTA inspection report, for the Twin Peaks Tunnel include structural joints, lagging timber and missing fire-proofing, among others. Type I conditions need to be addressed, the report states, and one showed "[v]ertical load carrying capability of concrete beams and slab(s) may be compromised."
BART did a similar study about a decade ago, only to find that their more stringent constructions were also seismically vulnerable.
San Francisco State University engineering professor Elahe Enssani reviewed the inspection reports for the Examiner, concluding that further, seismic testing should be done -- including soil testing and possible computer modeling.