For the second time this year, TriMet is shutting down all light rail service as well as the Portland Streetcar due to adverse weather conditions.
Last time: ice. Today: heat. The transit agency announced Sunday afternoon that it is suspending all MAX service through Tuesday as a result of the record-breaking heat bearing down on Portland.
According to TriMet’s website, temperatures over 100 degrees cause the overheard copper wires on the MAX to expand and sag, forcing the trains to slow. Over the last few years, the agency has added counterweights and rail anchors to mitigate delays, but this weekend’s unprecedented heat pushed the infrastructure to its limit.
“Our system was designed to operate up to 110 degrees—the most extreme temperatures you’d expect for the Pacific Northwest,” said TriMet spokesperson Tyler Graf. “But even then, as temperatures start exceeding 100 degrees, more strain is put on the system. Today our overhead wire was at 120 degrees and our rail was at 140 degrees, so we had reached our limits.”
TriMet had previously suspended both MAX and bus service during February’s ice storm.
Bus lines will continue to run as normal, and fares will not be enforced for passengers headed to cooling shelters.