The state border between Arizona and California was originally set by the once-meandering Colorado River. The Army Corps of Engineers straightened the river, then Federal and State Governments set a fixed boundary in 1963. But the states did not relinquish claims to the lands along now-dry river beds.
In 2002, the governors of Arizona and California signed laws to give up claims outside their official state boundaries. The land is near Yuma, Arizona about 20 miles north of the U.S. - Mexico border. California assumed authority of over 6 square miles on its side of the official boundary. This land is on Arizona's side of the old river. In exchange, California gave up claims to 11 square miles on Arizona's side of the official line. The actual exchange of the land would take several years, because the land had to be assessed and surveyed.
"Swap to end decades-old Arizona-California dispute." Tucson Citizen. 19 September 2002. Page 1.
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