U.S. Supreme Court
Nebraska v. Iowa, 143 U.S. 359 (1892)
Nebraska v. Iowa
No. 4, Original
Argued January 29, 1892
Decided February 29, 1892
143 U.S. 359
When grants of land border on running water and the banks are changed by the gradual process known as accretion, the riparian owner's boundary line still remains the stream, but when the boundary stream suddenly abandons its old bed and seeks a new course by the process known as avulsion, the boundary remains as it was, in the center of the old channel, and this rule applies to a state when a river forms one of the boundary lines.
The law of accretion controls the Missouri River, as elsewhere, but the change in the course of that river in 1877 between Omaha and Council Bluffs does not come within the law of accretion, but within that of avulsion.
The Court stated the case as follows: