Open Trip Planner was identified as the most promising open source multi-modal trip planning software. Open Street Map, which provides mapping data to Open Trip Planner, is one of the most well-known open source international repository of geographic data. General Transit Feed Specification, which provides transportation data to Open Trip Planner, has been the standard for describing transit systems and platform for numerous applications. Together, when used to implement an instance of Open Trip Planner, these software has been helping in traffic decongestion all over the world by assisting commuters to shift from using private transportation modes to public ones. Their potential however goes beyond providing multi-modal public transportation routes. This paper aims to first discuss the researchers' experience in implementing a public transportation route planner for the purpose of traffic decongestion.The researchers would examine the prospective of using the system for disaster preparedness and recovery and concrete ways on how to realize them.