Res 2020-049/adopting the Community Development Block Grant-Mitigation (“CDBG-MIT”) Action Plan that provides for the allocation of the $24,012,000 from the United Stated Department of Housing and Urban Development

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CDBG-MIT Action Plan City of San Marcos,'TX The City ofSan Marcos, Texas was inundated with historic flash and river flooding inHays County ontwo separate occasions within six months ofeach other in2O15. The first event, now called the "Memorial Day Floods", occurred overnight on May 231d and early May 24m. May 2015 has been documented by the National Weather Service 8othe wettest month in Texas History, with well above -normal rainfall during the first two to three vvemka of the month. A persistent area of |ovv pressure over the western United States brought multiple rain events throughout the month of May that saturated soil throughout south-central Texas. Bythe time Memorial Day weekend arrived, much of the region was at least 2'4 inches (100- 30096) above normal. These wet antecedent conditions meant that any new rain, and especially heavy rain, would become rapid run-off directly into rivers, streams, and flash flood prone areas. This "worst-case" scenario came to pass Memorial Day weekend. A thunderstorm cluster organized west of Hays County on Saturday afternoon and produced upwards of 12 inches of rain in less than six (0) hours. The majority of this rain fell in the upper reaches of the Blanco River watershed at rates that exceeded four (4) inches per hour as thunderstorms merged and regenerated for hours over southern Blanco and eastern Kendall counties. Most of the rain fo|| from Saturday afternoon into the overnight hours of early Sunday morning, leading to a rapid rine in the Blanco and San MoroOa rivers. The Blanco River mtVVimber|ey rose from near five (5) feet at 9 p.m. on May 23rd to near 41 feet by 1 am. on May 24th. The Blanco River rose five /5\ feet every 15 minutes just before midnight. equating toa 20 -foot rise along the river within o one-hour time frame. Numerous high-water rescues occurred throughout the late evening and morning hours along the banks of the Blanco River and eventually the San Marcos River. The resulting flash flooding caused a tragic loss of life and extreme property damage. Rescue and recovery efforts stalled on May 25th as another round of severe weather struck the neighboring counties ofWilliamson, Travis, Bastrop and {|o|dvve||. Large areas ofthese counties experienced flash flooding and tornados. Another catastrophic flood event took the area on October 30, 2015' referred toaathe "All Saints F|oOd".vvher8vvoterC8uaedpOrtionnof|nteratate35iobeo|oaedforas9oondti08thatyen[. The impacts of this event were widespread, leading to the closing ofAuniin-Bergetrom International Ai[pod, approximately 30 miles away. The National Weather Service reported "nearly 0 inches of rain ... within anhour ... flooding the ground floor of the Austin Air Traffic Control Tower and Terminal Roder Approach Control facility." Elsewhere in Texas, some areas received more than 10 inches of rain with heavy rains washing away RVa, bOatu, and trailers along the Guadalupe River in New Braunfels, Texas. The powerful waters of the All Saints Flood struck Cypress Creek in Wimberley, the Blanco River, and the San Marcos River, causing additional property damage and delaying recovery efforts from the previous flood. However, the oonnnounitv`e heightened sense of awareness and improved reaction to alerts translated to DO |ooe oflife during the All Saints Flood. Both events were considered historical flood events for Central Texas, but for different reasons. The PWm[noria| Day Flood was noted for its extreme water velocities, analogous tothe velocities of Niagara Falls. The All Saints Flood was noted for the extreme volume of precipitation in such a short