In 2011, the National Park Service put in place a policy to encourage national parks to end the sale of bottled water. The aim was to cut back on plastic litter.
It was not actually an outright ban — but 23 out of 417 national parks, including Grand Canyon National Park and Zion National Park, implemented restrictions on bottled water sales. The parks encourage visitors to use tap water and refillable bottles instead.
Now, The Trump administration has reversed this Obama-era policy.