It is situated north of Fort Stevens State Park and the Clatsop Spit, east of Cape Disappointment, and just south of Ilwaco, Washington.

[2][3] According to an 1889 description in the Coast Pilot of California, Oregon, and Washington: This low, sandy island is the visible danger in the middle of the entrance to the river.

It consists of loose sand raised a few feet above the river and covered with stranded trees, drift logs, etc., brought down by the freshets.

Formerly the North Channel ran around the northeast side of this island, but the shoal from its northeast side has spread towards the Chinook Shoal, which also has developed towards Sand Island, and now there is passage-way for only nine or ten feet of water in place of four fathoms.

During the fishing season there are sometimes net-racks and other temporary buildings on Sand Island for the accommodation of fishermen.