Reducing Waste in National Parks Act This bill directs each regional office of the National Park Service (NPS) to establish a program to recycle and reduce the use of disposable plastic bottles within each NPS unit located in its region. NPS regional offices may eliminate the sale of water in disposable plastic bottles within their NPS units after having considered several specified factors. Where, prior to enactment of this bill, an NPS unit does not offer water for sale in disposable plastic bottles, the unit may continue that practice if it submits to the regional office an evaluation of those factors. NPS regional offices shall develop for each NPS unit a proactive visitor education strategy to address visitor expectations of water availability and explain the rationale for the program.