Prior appropriation water rights

Prior appropriation water rights are a way that people can use water from rivers and streams. When a person wants to use water, they can go to the government and ask for permission to take water from the river. If they get permission, they gain rights to that water and can use it to do things like farm, water their animals, or wash their clothes. It's a bit like owning the water, but it's more like renting the water. So the person who got permission can use the water, but if another person comes along later and wants to use it too, the first person's rights might get moved around so that they have to share the water.