Over 100 irrigation projects and systems can be found on Indian reservations primarily across the western United States. The scarcity of water in much of the western United States makes irrigation critical to agricultural activities. The Department of the Interior's Bureau of Indian Affairs (BIA) manages 16 irrigation projects on Indian reservations in the western United States. This book focuses on BIA's estimated deferred maintenance cost for its irrigation projects; shortcomings that the Government Accountability Office (GAO) identified in BIA's management of its irrigation projects; and issues GAO identified that needed to be addressed to determine the long-term direction of BIA's irrigation program.