The Indian Affairs offers an extensive scope of programs that covers the entire range of Federal, State and local government services. Programs administered by either Tribes or Indian Affairs through the Bureau of Indian Education (BIE) include an education system consisting of 183 schools and dormitories educating approximately 42,000 elementary and secondary students and 28 tribal colleges, universities, and post-secondary schools. Programs administered through the Bureau of Indian Affairs (BIA) include social services, natural resources management on trust lands representing 55 million surface acres and 57 million acres of subsurface minerals estates, economic development programs in some of the most isolated and economically depressed areas of the United States, law enforcement and detention services, administration of tribal courts, implementation of land and water claim settlements, housing improvement, disaster relief, replacement and repair of schools, repair and maintenance of roads and bridges, and the repair of structural deficiencies on high hazard dams, the BIA operates a series irrigation systems and provides electricity to rural parts of Arizona.