If water flow decreases, what happens to those with prior appropriation rights?

If water flow decreases, those with prior appropriation rights are protected under the doctrine of prior appropriation, which operates on the principle of "first in time, first in right." This means that the earliest users who have established their rights to use a specific quantity of water are entitled to maintain their access to that water, even in times of scarcity. In essence, as the water supply diminishes, those who have historically used the water first retain their rights over newer users. This system prioritizes the needs of established users and creates a framework that allows them to protect their interests during periods of low water availability.

In contrast, other options suggest different scenarios that do not align with the principles of prior appropriation. The notion that all users must share water equally or that prior users would automatically lose their rights does not reflect the legal realities governing water rights under prior appropriation. Additionally, suggesting that those who stop using water would lose their rights overlooks the established priority of users who have historically used and claimed their rights. Thus, the correct understanding emphasizes the continuing rights of first users in a context of reduced water flow.