The island is bounded on the north by South Mokelumne River, on the east by Little Potato Slough, on the south by Potato Slough, and on the west, Mokelumne River.
The island is bounded on the north by South Mokelumne River. This was on the east by Little Potato Slough. This was on the south by Potato Slough, and on the west. The west was Mokelumne River.