Poor Houston. The city’s new light rail line was supposed to help revitalize downtown. Instead, as accidents mount, it’s garnering the wrong kind of attention on local news reports. It took the line less than three months to rack up 21 accidents on just seven and a half miles of track. Here’s how it stacks up against other systems: Portland had 15 accidents in its first year of operation. San Diego counted 27 for their first year. Dallas had six in the first six months. And all of those cities have lines longer than Houston’s. During Super Bowl weekend, one ESPN writer claimed that Houston’s light rail has the makings of a rather sinister urban legend: The light rail has been the running joke of the trip — people are telling apocryphal stories about these accidents, and you never know what to believe anymore. It’s like a cross between Billy Joel’s Mercedes and the Boogey Man. And that was a month ago. Good thing the Super Bowl isn’t in March.