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Some Record Floods in Central Texas (Info From USGS website) Location and area that collects the water Blanco at .Kyle, 412 square mile drainage Upper Guad at Kerrville, 510 sq. mile drainage •. •- . t • Year Peak in cubic feet /second 1998 105$000 1952 115,000 1929 139,000 s �+ r MI Q.��► WITStIUi 1 i North • near • sq. mi. drainage 1932 a i 1,11, 2002 Medina at Bandera, 328 sq. mile • it Note: Divide the cfs (cubic feet per second) by the square miles of drainage for each of these flood events to get a ratio of flood flow per square mile of drainage. In the "Great Flood of 1998" on the Blanco, that ratio was 255. In the North Fork Guadalupe flood near Hunt in 1932, the ratio is 828. All of the floods listed above have a ratio far above the 1998 flood. If you multiply that 828 by the square miles in the Blanco drainage, you will get a flood event of 341,136 cfs. This is over three times the flood of 1998 on the Blanco. Because these flood events are common around San Marcos, it is perfectly understandable that similar floods could happen - - -it is only a matter of time. It is urgent for public health and safety reasons building is not allowed at least in the 100 year flood plains, and that there be wide buffer zones of no -build areas around streams. This will prevent loss of life and property for future citizens and business owners in San Marcos. The Blanco River needs a wide buffer zone around it. It is essential to remember that San Marcos River will have floods that will overwhelm the flood control dams, if heavy rainfall hits that particular area, plus the Blanco can cause the San Marcos River to flood, by backing up water and sending it upstream from the confluence. The federal flood plain maps do not really consider these specific local realities.