Recent crises stemming from diminishing groundwater resources highlight the failure of existing water allocation agreements to account for changing circumstances. This note focuses on two case studies—a dispute over the All-American Canal between the United States and Mexico and a decade-long litigation between Kansas and Colorado regarding the Arkansas River Compact. Domestic and international issues stem from the same challenges of highly technical decisions, changing circumstances, and historical sensitivity of water rights. This Note argues that domestic and international water agreements place too much emphasis on onetime allocations despite warnings that imposing hard and fast rules unnecessarily burdens the ability to adapt to future changes in water conditions. These two case studies further demonstrate that traditional ex post dispute and litigation mechanisms are no longer adequate. After considering challenges to reform, this Note argues that the increasing urgency of water crises around the world have made conditions ripe for institutional change. As a solution, this Note proposes creating joint management institutions that provide ongoing expert administration for the changing dynamic of water resource crises.