In this case, the Court decided the exact border within the Savannah River and whether islands should be a part of Georgia or South Carolina.

[2] In a subsequent 1922 Supreme Court decision, also called Georgia v. South Carolina, 257 U.S. 516, also held that all islands in the river belong to Georgia, but that the border should be in the middle of the river between the two shores, with the border halfway between any island and the South Carolina shore.

)[4] The Savannah River north of Elba Island was particularly wide, and the Army Corps of Engineers built a training wall to narrow the channel to prevent it from filling up with silt.

[6] A perpendicular line drawn from each of these angles results in an overlapping 27 degree wedge claimed by both states.

[7] Justice Blackmun delivered a plurality opinion and held that the new island on the South Carolina side of the border belonged to that state rather than Georgia.

[8] The Court awarded Denwill and Horseshoe Shoal to Georgia because its creation was "primarily avulsive in nature."

[9] The Court also set a compromise seaward boundary drawing it perpendicular to a line between Tybee Island and Hilton Head.