We propose to conduct a flood vulnerability assessment of the City of Tucson, Arizona’s transportation systems with special reference to low-income and minority neighborhoods. Short-term flooding from extreme storm events poses a serious challenge to transportation system reliability and emergency response in cities across the United States. This problem, which is anticipated to grow over the next century due to climate change, is often hardest on vulnerable populations, including low-income and minority neighborhoods. Our work will advance national research methods for assessing multi-modal transportation degradation due to extreme storms. We will identify priority locations for Tucson to make transportation improvement investments pursuant to its new Green Infrastructure (GI) initiative for the purpose of mitigating urban transportation system flooding. This will include increasing equitable accessibility to the multi-modal transportation network by low-income and minority neighborhoods. As a case study, our proposal has national flood hazard transportation vulnerability and equity implications. The proposal has three stages. In Stage 1 we will estimate flood conditions based on extreme precipitation events with a digital elevation model (DEM) constructed using LiDAR data. In Stage 2 we will analyze neighborhood transportation vulnerability based on overall transportation system performance degradation with special reference to low-income and minority neighborhoods. Stage 3 will include our efforts to communicate our findings broadly, including a direct application to current city and county Green Infrastructure (GI) planning efforts. This research will serve as a proof of concept for a larger, long-term project to advance national research methods to reduce the impact of chronic flooding on the multi-modal transportation network.