Water Rights Protection Act of 2021 This bill prohibits the Departments of the Interior and Agriculture from conditioning the issuance, renewal, amendment, or extension of any permit, approval, license, lease, allotment, easement, right-of-way, or other land use or occupancy agreement (permit) on the transfer of any water right to the United States or on any impairment of title granted or otherwise recognized under state law by federal or state action; requiring any water user (including a federally recognized Indian tribe) to apply for or acquire a water right in the name of the United States under state law as a condition of the issuance, renewal, amendment, or extension of such a permit; or conditioning or withholding the issuance, renewal, amendment, or extension of such a permit on limiting the date, time, quantity, location of diversion or pumping, or place of use of a state water right beyond any limitations under state water law, or on the modification of the terms and conditions of groundwater withdrawal, guidance and reporting procedures, or conservation and source protection measures established by a state. In developing any rule or similar federal action relating to the issuance, renewal, amendment, or extension of any permit, such departments (1) shall recognize the longstanding water use authority of the states and coordinate with the states to ensure that any federal action is consistent with applicable state water law, and (2) shall not adversely affect the authority of a state in permitting the beneficial use of water or adjudicating water rights.