Water is a precious resource. Throughout Colorado, water has historically been allocated according to the rule of prior appropriation, where the principal method of allocation is “first in time, first in right.” As Colorado changes over time, the rule’s inflexible application has resulted in economically inefficient and environmentally detrimental consequences. This is exemplified in the unreliable water distribution of the Windy Gap Project, and the projected detrimental environmental consequences of the Windy Gap Firming Project. Thus, Colorado water law must change to protect the overuse and misuse of such a scarce resource. Despite explicit renunciation of both the public trust and public interest doctrines, Colorado water law must evolve to incorporate the protective values and ideals inherent in those principles. To do so, Colorado should create a public interest system that outlines specific values of importance to the community. Then, the state should use those values to establish a comprehensive public trust that can be integrated with the current prior appropriation system.