Arizona is a party to two interstate water compacts; the Colorado River Compact of 1922 and the Upper Colorado River Basin Compact of 1948. Arizona and California have a bit of an adversarial stand with respect to water and the Colorado River Compact. California has a more senior water right priority to Arizona with respect to the Colorado River Compact. This adversarial positioning has led to litigation between the two states. With water becoming more scarce in the Western states due to climate change and drought, it can be anticipated that more litigation between the two states will arise.
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