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Treaties, compacts, and equitable apportionment decrees


While each state is free to allocate water under whatever system it adopts, subject to federal law, no state can allocate more than its own share of interstate rivers. A state’s share may be established by interstate compacts, equitable apportionment decrees of the United States Supreme Court, and international treaties.  

Colorado’s waters, for example, are subject to nine interstate compacts, three apportionment decrees and one treaty, all of which impose substantial limitations on the use of water in the state. When reviewing water availability for major projects, one should expect a water lawyer, with engineering assistance, to analyze carefully the present and future impact of interstate compacts.  

In addition, compacts and interstate decrees are increasingly implicated in change of use and augmentation plan proceedings where there is potential to affect stateline flows. Curtis, Justus, & Zahedi, LLC has experience in analyzing interstate stream obligations and developing client solutions that fit within those requirements.