[2][3] It is north of Pittsburg,[2][3] separated from Browns Island to the west by a slough.

[4] Winter Island is part of Contra Costa County, and managed by Reclamation District 2122.

[5] It is shown, labeled "Ruckels Island", on an 1850 survey map of the San Francisco Bay area made by Cadwalader Ringgold[6] and an 1854 map of the area by Henry Lange.

[7] In 2009, Brusco Tug and Barge, a tugboat company, pled guilty to illegal dredge dumping near the island between 2003 and 2007.

[2] This Contra Costa County, California–related article is a stub.