It was created by the filling of the reef flats during incremental dredging of Honolulu harbor and Ke‘ehi lagoon. The village of Kou, inland of it, had a long history of settlement. It originally consisted of marginal sandy lands on an elevated coral reef platform named Kahololoa.
For a time it was called Anuenue Island; that changed in 1969 when a proclamation by the Governor declared the Island shall be named Sand Island. One of the few lasting legacies of the Island’s former name is Anuenue Fisheries Research Center (AFRC,) a base yard, hatchery and culture center for DLNR’s Division of Aquatic Resources – it’s still operating on the Island.