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Ramsey County | Multi-Jurisdiction Hazard Mitigation Plan 41 and specifies preplanned actions to be followed to minimize potential property damage and loss of life. Every EAP must be tailored to site-specific conditions but generally contains six basic elements: • Notification flowchart • Emergency detection, evaluation, and classification • Roles and responsibilities • Preparedness activities • Inundation maps • Appendices Dam failure is the collapse or failure of an impoundment that causes significant downstream flooding. The principal consequences of dam failure are injury, loss of life, and significant downstream property damage. The energy of water stored behind even a small dam is capable of causing loss of life and significant property damage to people living downstream. The collapse or structural failure of a dam may be caused by severe storm, earthquake, improper maintenance, erosion, or acts of terrorism. A failure in a dam upstream can cause additional strain and failure risk to dams further downstream. The Battle Creek dams are the only dams located within Ramsey County that are classified as High and have developed EAPs for review. The Coon Rapids Dam and the St. Anthony Falls Upper and Lower Locks and Dams are classified as significant and have also written EAPs. 3.6.4 HISTORY There have been no dam failures in Ramsey County in the past, though there have been several dam failures within the State of Minnesota. Most reported failures have been in low hazard dams, with at least one exception; the Thomson Dam in northeastern Minnesota overtopped in 2012 due to heavy rains, causing significant damage to its hydroelectric station and contributing to flooding downstream. There have been no known deaths, injuries, or property damage from dam or levee failures in the county. The effects on life and property in the area could be significant if a dam were to fail because of the nature of the built environment underneath it. 3.6.5 PROBABILITY The probability of a specific dam failing in any given year is extremely low. Some common causes of dam failures include overtopping, foundation defects, cracking, inadequate maintenance, or piping and seepage. According to the Association of State Dam Safety Officials, the primary cause of reported dam failures between 2010 – 2019 was overtopping, most often due to flooding events. 3.6.6 CLIMATE CHANGE IMPACTS Climate change can significantly affect the risk and severity of dam and levee failures. The changes most likely to impact Ramsey County are: • Changes in seasonal patterns and increased precipitation intensity – more frequent and intense rainfall events or earlier spring snowmelt can result in higher risk of flooding, putting additional stress on dams and levees. According to the Minnesota Department of Natural Resources Climate Change Information website, heavy rains are now more common in Minnesota and