Rio Grande border disputes

The Rio Grande (Río Bravo del Norte) has changed course several times in recorded history, leading to a number of border disputes, both international (involving Mexico and the United States) and between individual U.S. states:

Numerous border treaties are jointly administered by the International Boundary and Water Commission, which was established in 1889 to maintain the border, allocate river waters between the two nations, and provide for flood control and water sanitation. Once viewed as a model of international cooperation, in recent decades the IBWC has been heavily criticized as an institutional anachronism, by-passed by modern social, environmental and political issues.

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