Georgia v. South Carolina, 497 U.S. 376 (1990), is one of a long series of U.S. Supreme Court cases determining the borders of the state of Georgia. 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. It also decided the seaward border. Background In 1787, the two states agreed in the Treaty of Beaufort that the boundary along the Savannah River was the river's "most northern branch or stream," "reserving all islands in [the river] to Georgia". 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. Since the 1922 case, a number of new islands had been created in the river between the city of Savannah and the ocean, due to the deposit of dredging spoilage or the natural deposit of sediments. In some cases, the new islands were on the South Carolina side of the previously drawn boundary, and Georgia claimed that once a new island emerged, the border should be moved to the midpoint between the new island and the South Carolina shore of the river. In some cases, the state of South Carolina had been collecting property tax from the land owners and policing the land in question for a number of years. When an island causes the border to leave the middle of the river, it raises the question as to how the border line should return to the middle of the river at each end of the island. South Carolina advocated a right angle bend at each tip of the island, while Georgia advocated a "triequidistant" method which kept the border an equal distance between the two shores and the tip of the island (resulting in a smooth curve.) 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. The Corps also filled the area behind the training wall with dredging spoilage. Both South Carolina and Georgia claimed the land that was created behind the training wall, even though it was