William Blomquist & Tanya (Columbia University, New York, New York, USA) Heikkila 
Common Waters, Diverging Streams 
Linking Institutions and Water Management in Arizona, California, and Colorado

This book is a firsthand investigation into water management in a fast-growing region of the arid American West. It presents three states that have adopted the conjunctive management of groundwater and surface water to make resources go further in serving people and the environment. Yet conjunctive management has followed a different history, been practiced differently, and produced different outcomes in each state. The authors question why different results have emerged from neighbors trying to solve similar problems with the same policy reform. Common Waters, Diverging Streams makes several important contributions to policy literature and policymaking. The first book on conjunctive water management, it describes how the policy came into existence, how it is practiced, what it does and does not accomplish, and how institutional arrangements affect its application. A second contribution is the book“s clear and persuasive links between institutions and policy outcomes. Scholars often declare that institutions matter, but few articles or books provide an explicit case study of how policy linkages work in actual practice. In contrast, Blomquist, Schlager, and Heikkila show how diverging courses in conjunctive water management can be explained by state laws and regulations, legal doctrines, the organizations governing and managing water supplies, and the division of authority between state and local government. Not only do these institutional structures make conjunctive management easier or harder to achieve, but they influence the kinds of problems people try to solve and the purposes for which they attempt conjunctive management.