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ICIWaRM Publishes Study of Water Allocation in the U.S. as part of Collaborative Program with Brazil’s Agência Nacional de Águas

Published March 20, 2015
IWR 2014-R-04 Report Cover

IWR 2014-R-04 Report Cover

ALEXANDRIA, VIRGINIA. The Institute for Water Resources’ (IWR) UNESCO-affiliated International Center for Integrated Water Resources Management (ICIWaRM) recently published Water Allocation in the U.S., a report prepared for Agência Nacional de Águas (ANA) in accordance with a 2013 ANA-USACE Agreement Component with an emphasis on "Water Rights as a Commodity." The country of Brazil is confronting significant and increasing water resources challenges. Decreasing water availability and competing demands on water are placing increased pressures on state and national governments to more effectively manage available water resources.

An agency charged with management and sustainable use of water resources at the national level is the ANA. Created in 2000 to help implement a new national water policy and system of water resources management, ANA continues to investigate ways to improve the planning, monitoring, allocation, and regulation of Brazil's water resources. As part of that effort, ANA requested assistance from the U.S. Army Corps of Engineers (USACE) through a government-to-government agreement on several water resources planning and management topics.

One of these requests was a summary of U.S. water allocation policies. USACE’s Mobile District, as project manager of ANA’s request for USACE assistance, passed this request to IWR to develop a response, resulting in the report.

Since surface and ground water allocation in the U.S. is managed at the state level, the methods used in the U.S. vary between each state and territory. As a result, the following report does not attempt to provide a holistic report or assessment of U.S. water allocation policies, but rather describes the two dominant philosophies guiding U.S. water allocation: riparianism and prior appropriation. Using these philosophies, individual state water allocation practices (e.g., monitoring, allocation, regulation, etc.) within watersheds of interest to ANA were reviewed to provide notable water allocation examples from different parts of the country.

While the examples selected for this report were chosen to address situations of likely interest to Brazil, the substance of the report is not specific to Brazil, and as such may be of interest to others experiencing challenges in water allocation. For this reason, this report is being made available to the broader international community through IWR’s UNESCO-affiliated International Center for Integrated Water Resources Management (ICIWaRM).

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