Kuapa Pond was a shallow lagoon in Hawaii that was separated by a barrier beach from a bay leading to the Pacific Ocean. Under Hawaiian law, these types of ponds had long been deemed private property. The owners of Kuapa Pond leased the pond and surrounding land to Kaiser Aetna (defendant) to develop it into a marina. Kaiser Aetna dredged and deepened the pond and transformed it into a private marina that was navigable from the bay. A dispute arose between Kaiser Aetna and the government in which the government asserted that Kaiser Aetna had no right to exclude the public from the marina because it now amounted to navigable waters. The United States (plaintiff) eventually sued Kaiser Aetna in federal court to assert this claimed right. The district court held that the marina was navigable waters and therefore subject to regulation by the government but that the government did not have the right to open the marina to the public without providing just compensation to the owner. The court of appeals overturned the district court and held that the public had acquired a right of access to the marina once it became navigable. Kaiser Aetna appealed.