Before a BART train derailed near Concord last month over “track warping” on a surface that reached 140 degrees, the agency apparently did not follow a process that they’d used in years past to prevent such derailings during extreme heat.

Remember last month when a BART train partially derailed near Concord during that late June heat wave? Considering it happened at rush hour, the whole thing could have been a lot worse. There were about 50 people onboard, and according to the Bay Area News Group, “A small number of them reported minor injuries.”

The day after the incident, NBC Bay Area reported that the tracks’ surface temperature hit 140 degrees, and they’re designed to not exceed 114 degrees, or else there’s trouble. “Whenever that temperature gets more than 20 degrees above that neutral temperature of the rail that opens the possibility that the rail could misalign,” BART spokesperson Chris Philippi told that station. “It appears that may have happened in this case.”

But what’s odd is that the temperature issue has happened before, but not the derailing. A follow-up NBC Bay Area report points out that BART has slowed trains in the past to prevent this kind of thing. “The agency later acknowledged they had no formal policy to reduce speed, even though it had cut speeds in half during a similar heat wave back in 2017,” according to the station.

“This is something that every rail operator should have a set policy that goes into place under these conditions — they know what the danger condition is, we dodged a bullet,” UC Boulder environmental design professor Paul Chinowsky. “To have so few injuries is almost unheard of, so, it was truly, truly fortunate that there weren't more people injured and killed in the event.”

It does seem BART has realized this and gotten the message. In a July 8 follow-up to the incident, the transit service wrote, “BART’s review indicates a rapid increase in ambient temperatures caused the rail to misalign.” They added, “As BART is able to identify sections of track that are particularly susceptible to heat-related impacts, it will reduce the threshold temperature to apply speed restrictions for trains in those areas when temperatures are forecast to exceed 100 degrees Fahrenheit.”

And they’ll have to, because this manner of occurrence is likely to happen again more frequently.

“This is just going to keep getting worse,” Chinowsky tells NBC Bay Area, referring to climate change. He noted other rail operators have employed heat sensors for alerting purposes, or simply painted rails white to reflect the heat away.

Related: BART Trains to SFO Briefly Halted After Tree Falls Onto Tracks Amid Gusty Winds [SFist]

Image: Pi.1415926535 via Wikimedia Commons