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Sherburne County Multi -Hazard Mitigation Plan, 2020 No program gaps or deficiencies specifically related specifically to landslides were identified. Mitigation measures related to flooding will also address landslides and soil erosion concerns in Sherburne County. 4.3•12 Dam & Levee Failure Dams are structures that retain or detain water behind a large barrier. When full or partially full, the difference in elevation between the water above the dam and below creates large amounts of potential energy, allowing the chance for failure. Dams can fail due to either i) water heights or flows above the capacity for which the structure was designed; or 2) deficiencies in the structure such that it cannot hold back the potential energy of the water. If a dam fails, issues of primary concern include loss of human life/injury, downstream property damage, lifeline disruption (transportation routes and utility lines required to maintain or protect life), and environmental damage. Dams require constant monitoring and regular maintenance to insure their integrity. Dam & Levee Regulation The agencies with regulatory authority of dams in Minnesota are: • The MN DNR Dam Safety Program has the mission of protecting the life and safety of people by ensuring that dams are safe. Minnesota's program sets minimum standards for dams and regulates the design, construction, operation, repair, and removal of dams. Both privately and publicly owned dams are regulated. • The U.S. Army Corp of Engineers (USACE) maintains the lock and dam system on the Mississippi River and has regulatory authority over the flood control dams that it owns. USACE also participates with local communities in all phases of flood control that includes dams, levees, or other means. • The Federal Power Act (FPA) authorizes the Federal Energy Regulatory Commission (FERC) to issue exemptions or licenses to construct, operate and maintain dams, water conduits, reservoirs, and transmission lines to improve navigation and to develop power from streams and other bodies of water over which it hasjurisdiction. 3.6 U.S.C. § 797(e). Regulatory tools include the Federal Power Act, Public Utility Regulatory Policies Act, the Electric Consumers Act of 1.986 and the Energy Policy Act of 3.992. Dam & Levee Failure History in Sherburne County According to the State Dam Safety Engineer at the MN DNR, there have not been any cases of dam failure in Sherburne County. To determine the probability of future dam or levee failures, all past -observed dam and levee failures in the County and the period in which they occurred were examined. Because the County has zero reported failures, the relative frequency of a dam or levee failure is o per year. This relative frequency can be used to infer that the probability of a dam or levee failure occurring in the future is very low. Dam & Levee Failure and Climate Change Dams are designed based on assumptions about a river's annual flow behavior that will determine the volume of water behind the dam and flowing through the dam at any one time. Changes in weather Page186