Prescriptive rights have a long tradition in American property law. Many trail corridors and public access to beaches have been obtained through legal prescription—through continual and well-documented usage over the rights of private property holders.

As a water right holder (either riparian or appropriative) you could lose your water rights through "prescription." The situation starts where someone using water you might have used. If they use it for five years or more without you challenging their usage, then they have probably acquired their rights to water through prescription.

Water Rights Primer