Paper: Green Light for Adaptive Policies on the #ColoradoRiver: “The interplay between the river’s hydrologic and institutional history demonstrates that appropriate adaptive tools exist and have been used well in the past” — John Fleck and Anne Castle #COriver #aridification

Colorado River “Beginnings”. Photo: Brent Gardner-Smith/Aspen Journalism

Click here to read the paper (John Fleck and Anne Castle). Here’s the abstract:


The Colorado River is a critical source of water supply for 40 million people in nine states spanning two nations in western North America. Overallocated in the 20th century, its problems have been compounded by climate change in the 21st century. We review the basin’s hydrologic and water management history in order to identify opportunities for adaptive governance to respond to the challenge of reduced system flows and distill the ingredients of past successes. While significant advances have been made in the first two decades of the 21st century, these past actions have not been sufficient to halt the declines in the basin’s reservoirs. We find that the mix of federal, state, and local responsibility creates challenges for adaptation but that progress can be made through a combination of detailed policy option development followed by quick action at hydrologically driven moments of opportunity. The role of directives and deadlines from federal authorities in facilitating difficult compromises is noted. The current state of dramatically decreased overall flows has opened a window of opportunity for the adoption of water management actions that move the river system toward sustainability. Specific measures, based on the existing institutional framework and on policy proposals that have circulated within the Colorado River community, are suggested.

This map shows the Colorado River Basin and surrounding areas that use Colorado River Water, with four regions delineated, based on the degree to which flow is regulated and the channel physically manipulated. The dividing line for the upper and lower basin is Lee Ferry near Glen Canyon Dam.