Reducing Waste in National Parks Act This bill directs the National Park Service to establish a program for the National Park System to reduce disposable plastic products and, if applicable, eliminate the sale and distribution of disposable plastic products. Each regional office of the National Park Service must eliminate the sale of water in disposable plastic products and the sale and distribution of other disposable plastic products after consideration of several specified factors (e.g., the costs and benefits to overall operations). Each regional office must develop a proactive visitor education strategy to address visitor expectations of water availability and explain the rationale for the program and its implementation.