In the context of this report, NIPP stands for National Infrastructure Protection Plan. From the Executive Summary: "The Dams Sector delivers critical water retention and control services in the United States, including hydroelectric power generation, municipal and industrial water supplies, agricultural irrigation, sediment and flood control, river navigation for inland bulk shipping, industrial waste management, and recreation. Its key services support multiple critical infrastructure sectors and industries. Dams Sector assets irrigate at least 10 percent of U.S. cropland, help protect more than 43 percent of the U.S. population from flooding, and generate about 60 percent of electricity in the Pacific Northwest. The Dams Sector's significant economic and public safety benefits are countered by the magnitude of potential consequences associated with the failure, damage, or disruption of critical assets. […] Sector assets include dam projects, hydropower plants, navigation locks, levees, dikes, hurricane barriers, mine tailings, and other industrial waste impoundments. A large and diverse set of public and private entities own and operate these facilities under highly distributed regulatory oversight from Federal, State, and local entities. The National Inventory of Dams lists more than 87,000 dams, of which the private sector owns about 65 percent and State or local entities own about 31 percent. Individual State dam safety programs permit, inspect, and regulate about 80 percent of U.S. dams. The Federal Government owns and self-regulates only 4 percent of dams, yet these dams account for 80 percent of the largest and highest-consequence U.S. dams. The U.S. Army Corps of Engineers oversees all navigation locks and about 10 percent of U.S. levees."
Department of Homeland Security: https://www.dhs.gov/