13 - RESOLUTION ADOPTING THE 2017 LAMAR COUNTY MITIGATION PLAN

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Lamar County Multi- Jurisdictional Hazard Mitigation Plan Chapter Three 6. Vulnerability A building's construction is a key factor in withstanding the forces produced by earthquakes. Unreinforced Seismic risk uses the results of a seismic masonry buildings are most at risk in an earthquake hazard analysis, and includes both consequence and probability. - because the walls are prone to collapse outward. Steel www.wikipedia.org and wood buildings have more ability to absorb the I k, 0 energy from an earthquake. Wood buildings with proper foundation ties have rarely collapsed in earthquakes. The majority of homes in Lamar County are wooden structures. Most of Lamar County's seismic events are so small that they aren't felt but, these events could still be causing damage to the integrity of infrastructures. Because of the weak strength of existing earthquakes, and the low probability of significant event, information to quantify damage to infrastructure in the County has never been developed. It is the lack of planning that causes the county the most vulnerability. 7. Secondary Hazards Secondary hazards can include fire, landslides, collapse or structural failure of bridges, dams, overpasses, roads, and disruption of economic activity across the region. Dispersioon of contaminants from chemical spill and busted pipelines could also occur. Hazardous materials and other contaminants were not identified in the area, but will be addressed in updates of this plan. Ground movement during an earthquake is seldom the direct cause of death or injury. Most earthquake - related injuries result from collapsing walls, flying glass, and falling objects as a result of the ground shaking, or people trying to move more than a few feet during the shaking. 8. Overall Summary of Vulnerability and Impacts Earthquake Fads Largest recorded earthquake in the United States was a 9.2 that struck Prince William Sound, Alaska, March 28, 1964. Moonquakes ( "earthquakes" on the moon) happen less frequently and have smaller magnitudes than earthquakes on the Earth. The hypocenter of an earthquake is the location beneath the earth's surface where the rupture of the fault begins. The epicenter of an earthquake is the location directly above the hypocenter on the surface of the earth. From 1975 -1995 there were only four states that did not have any earthquakes reported. They were: Florida, Iowa, Damage from an earthquake centered in Lamar County is "Unlikely" but there is a small risk from earthquakes that may occur outside of Texas. Earthquakes in Lamar County are rare and the few events that have occurred were largely unfelt. There is concern as to the long term effects of the unfelt earthquakes on the integrity of numerous pipelines associated with the oil, gas, water and wastewater systems located within the County. However, these concerns do not appear to present significant problems and no information was found that would document damages to these systems. 137