Energy and Water Development and Related Agencies Appropriations Act, 2021 This bill provides FY2021 appropriations for U.S. Army Corps of Engineers civil works projects, the Department of the Interior's Bureau of Reclamation, the Department of Energy (DOE), and independent agencies such as the Nuclear Regulatory Commission. The bill provides appropriations for U.S. Army Corps of Engineers civil works projects, including for Investigations, Construction, Mississippi River and Tributaries, Operation and Maintenance, the Regulatory Program, the Formerly Utilized Sites Remedial Action Program, Flood Control and Coastal Emergencies, Expenses, and the Office of the Assistant Secretary of the Army for Civil Works. The bill provides appropriations to the Department of the Interior for the Central Utah Project and the Bureau of Reclamation. The bill provides appropriations to DOE for Energy Programs, including Energy Efficiency and Renewable Energy; Cybersecurity, Energy Security, and Emergency Response; Electricity; Nuclear Energy; Fossil Energy Research and Development; Naval Petroleum and Oil Shale Reserves; the Strategic Petroleum Reserve; the Northeast Home Heating Oil Reserve; the Energy Information Administration; Non-Defense Environmental Cleanup; the Uranium Enrichment Decontamination and Decommissioning Fund; Science; Nuclear Waste Disposal; the Advanced Research Projects Agency--Energy; the Title 17 Innovative Technology Loan Guarantee Program; the Advanced Technology Vehicles Manufacturing Loan Program; the Tribal Energy Loan Guarantee Program; the Office of Indian Energy Policy and Programs; Departmental Administration; and the Office of the Inspector General. The bill also provides appropriations to DOE for Atomic Energy Defense Activities of the National Nuclear Security Administration, Environmental and Other Defense Activities, and the Power Marketing Administrations. The bill provides appropriations to several independent agencies, including the Federal Energy Regulatory Commission and the Nuclear Regulatory Commission. The bill sets forth permissible and prohibited uses for funds provided by this and other appropriations Acts.