In 2008, prior to Hurricane Gustav making landfall, Rainwater was dispatched by Governor Jindal to assist then-New Orleans Mayor Ray Nagin to assist in managing the response and evacuation of the city. During Hurricane Katrina in 2005, Rainwater helped manage Louisiana's response, including evacuations from the I-10 Causeway in Jefferson Parish. In the immediate aftermath of the second flooding of New Orleans during the summer of 2017, New Orleans Mayor Mitch Landrieu dismissed the leadership of the Sewerage and Water Board of New Orleans and named Rainwater as Interim Emergency Manager of the utility, charging him with overseeing the water and drainage systems of the city through the end of hurricane season while making emergency repairs to the system.
