Grand Canyon National Park recently banned the sale of plastic water bottles. Discarded plastic bottles account for approximately 30 percent of the park’s waste, according to an National Park Service estimate. Zion National Park in Utah launched a similar program in 2008.

Hawaii Volcanoes National Park provides water stations and requests visitors bring bottles or buy reusable ones at the visitors’ center. Grand Canyon installed 10 water filling stations on the South Rim and three on the North Rim.

Yellowstone National Park has not considered a program like this, said Al Nash, YNP’s Public Affairs Officer. However, Nash said, “We have a very active and aggressive recycling program in Yellowstone which includes plastic bottles.”