13 - RESOLUTION ADOPTING THE 2017 LAMAR COUNTY MITIGATION PLAN

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Lamar County Multi- Jurisdictional Hazard Mitigation Plan HAZARD PROFILE: SECTION FIVE - FLOODING 1. DESCRIPTION Flooding is the most prevalent and costly disaster in the United States. Floods have the ability to roll boulders the size of cars, uproot trees, and transport building. Floods occur any time and are typically the result of dam failures, rains, or melting snows exceeding the absorptive capacity of the soil and the flow capacity of rivers, streams or coastal areas. At the point the water concentration hyper extends the capacity fo the flood way, the water enters the floodplain. Floods are most common in seasons of rain and thunderstorms. Floods can be associated with other natural phenomenon such as rainstorms, thunderstorms, hurricanes, earthquakes, tsunamis and rapidly melting snow. Lamar County is prone to two types of floods: Chapter Three Flooding - The accumulation of water within a water body and the overflow of excess water on adjacentfloodplain lands. Flood Plain - Is the land adjoining the watercourse or water body susceptible to flooding. Flash Flood Watch - Flash Flooding is possible. Be prepared to move to higher ground. Flood Warning - Flooding is occurring or will be occurring soon. Flash Flood Warning - A flash flood is occurring seek higherground. • Riverine Flood - occurs in the floodplain of a river or stream when the amount of water and the rate at which the moving increases. This type generally can be forecast in advance, and proper precautions taken to save lives. • Flash Flood - A type of Riverin flood that occurs after a heavy storm, when the ground cannot absorb the high amount of precipitation. This can occur when heavy precipitation falls on already saturated soils. Flash Floods occur rapidly with little warning. 2. Location Flood Hazard areas are determined using statistical analyses of records of river flow, previous occurrence information, topographic surveys, and hydrological analyses. FEMA's Flood Insurance Rate Maps (FIRMs) Identify areas subject to flood hazard. These include Special Flood Hazard Areas, which is defined as the area that will be inundated by the flood event having a one percent chance of being equaled or exceeded in any given year. The one - percent- annual- chance flood is also referred to as the base flood or 100 -year flood. Moderate flood hazard areas are Texas Flood Facts Centeral Texas has been identified as the most flash flood prone area in the U.S. by the National Weather Service Texas holds 6 of 12 world records for rainfall rates in 24 hours or less - USGS Texas leads the nation in the most flood related deaths. 20 million of 171 million acres are flood prone Texas has approximately 8 million