The second major equipment malfunction in six weeks onCaltrain tracks delayed riders up to 40 minutes during the Thursday morning commute after a broken rail was discovered.
The transit agency’s crews near the southbound tracks just north of the San Mateo station discovered the three-quarter-inch break in the rail at 6 a.m. The issue was fixed by 10 a.m., said Caltrain spokeswoman Christine Dunn and the track could not have been broken for long because maintenance checks were performed on the area six weeks prior.
Officials have yet to determine the cause of the crack but Dunn said there was no immediate threat the trains could have derailed, although the broken rail could have became dangerous had it gone undetected.
Caltrain riders are already dealing with the frustration of boarding four-car trains instead of the normal five-car trains. Hairline cracks were found on the lower portion of 14 railcars in early June and were immediately taken out of service. The cars have been taken by truck to Ohio where they are being fixed, and officials still do not know how the cracks occurred, Dunn said. Like the track concerns, Caltrain contends the railcar cracks were not immediately dangerous.
Caltrain also fought another danger this week: the sun. Trains must slow down to 60 mph, as opposed to the normal speed of 79 mph, when temperatures reach 95 degrees, as it does on the southern Peninsulaand South Bay occasionally. The heat can cause the tracks to expand, which could lead to derailment, Dunn said.
In 2000, the last time the agency experienced a heat-expanded track called a "sun kink," tracks stretched 2 feet in San Mateo because of the heat, sparking 75-minute delays.
"[Sun kinks] can cause a pretty good wreck if they’re running on high speed," said Dick Doughty, a national rail expert who follows Peninsula transportation. "Some [sun kinks] can pop out right in front of the train."
"If it’s not detected before any train runs over it, there is always the potential for a disaster," Reeves said.
Some riders were frustrated by Caltrain’s delays Thursday.
"I kind of needed to make it to work on time [Thursday] so it was a bit frustrating," said George Lane, who was bound for Foster City on Caltrain Thursday morning but decided to hop off at the Millbrae station and ride his bike there instead.
.75 inch Size of track break found Thursday morning
40 minutes Maximum delays caused by break
14 Railcars with cracks found in June
95 degrees Threshold for trains to reduce speed to avoid derailment
2000 Last time heat expanded tracks