Nature keeps finding new ways to punish Maryland for its location straddling north and south. A storm that dumps rain on Norfolk and snow on Philadelphia blankets this area with ice. Just when ice-bound commuters would be happy to abandon their cars and jump on mass transit, the light rail system fails. The same ice that has made the streets and sidewalks treacherous also coats the overhead electric power lines that energize light rail's cars. In effect the power lines are insulated, and the trains can't make contact.
Can't that problem be corrected? Could it have been avoided? Yes and no. There is no single technical device that would keep the overhead wires clear of ice. There are some methods, essentially crude ones, that can help. As for protecting against -- ice when the system was constructed, the options would have been less attractive. Drawing power from a third-rail is too dangerous when people can cross the right of way, as they can on the light rail. Diesel powered cars would have avoided the icing problem but created other, greater ones. That begs the question, however, whether enough thought was given to icing in the initial design.
While icing is not unknown on other transit systems, it is probably going to be more common here. Systems like Boston's struggle with snow regularly, but its colder air brings snow more often than rain. South of Maryland the precipitation pretty much stays liquid. Baltimore's location often places it on a narrow band with easily cleared snow to the north and harmless rain to the south. What comes down here as rain hits frosty metal and pavement, hardening into ice.
The icing problem is also a legacy of the decision to single-track much of the light rail system to save money. It limits trains to 15 minute headways, giving ice on the wires more time to build up. Running cars along the tracks more frequently, even empty, might be a crude but expensive method of breaking up the ice. The Mass Transit Administration is experimenting with a diesel-powered overhead scraper. Another possibility is sending a stronger electric charge through the power lines to warm them, but there remain technical obstacles.
Bad weather is one of mass transit's best marketing devices. Some people forced from their cars might stick with the train -- but not if it fails them when most needed. Not to mention the regular passengers who get fed up when the system shuts down. It's worth a major effort at the MTA to keep the light rail cars moving without fail.