Safe Beaches, Safe Swimmers ActThis bill establishes requirements to ensure an adequate staff of lifeguards at swimming areas and swimming beaches managed by the National Park Service, the U.S. Fish and Wildlife Service, the Bureau of Land Management, or the Bureau of Reclamation that are typically monitored by federally employed lifeguards during normal seasonal operating hours.If the Department of the Interior determines there is a staffing shortage of lifeguards that will leave a swimming area or beach unmonitored by federally employed lifeguards during normal seasonal operating hours, Interior may enter into an agreement with local government agencies to provide lifeguards. Interior must ensure that a local government agency providing lifeguard services is reimbursed for all reasonable costs it incurred in carrying out the agreement.The bill does not apply to short-term staffing shortages caused by temporary absences, such as an employee taking annual or sick leave.