When a massive fire caused a section of Interstate 85 to collapse in Atlanta in late March, the Metropolitan Atlanta Rapid Transit Authority (MARTA) swung into action. Before the fire was out, MARTA CEO Keith Parker joined city and state officials to quickly draft a transportation action plan for the hundreds of thousands of drivers whose commutes were thrown into disarray with the I-85 shutdown, which would last six weeks. The rebuilt section reopened the week of May 13.Recently, I had the opportunity to talk with Parker about how the agency handled the crisis. MARTA responded to commuters' needs by adding extra trains, buses and parking spaces at rail stations. Parker and agency officials also had a consistent communications plan in place to explain to Atlanta commuters how to use the MARTA system for their daily transit needs. For some of those riders, the I-85 detour period was their first time riding a MARTA bus or train.Key to MARTA's quick reaction was having a disaster plan in place, Parker told me. Agency staff regularly participate in crisis-response training."Whatever the case, something eventually will happen to a transportation network that will make public transit critically important," he said. "You have to plan for that eventuality."You can find out more about MARTA's response to the I-85 disaster by reading my feature story on ProgressiveRailroading.com.