California records
Common Watersnake in California
HarmlessNerodia sipedon

Yes. The Common Watersnake has been recorded in 2 California counties. It is non-venomous (harmless). Heavy banded or blotched body, round pupils, and a narrow head — unlike the cottonmouth's broad, blocky head.
California counties with Common Watersnake records
2 listedSee the full Common Watersnake profile or all snakes in California.