18-65 inches. Pale gray-brown or tan above with dark brown or black crossbars alternating on the back and sides; dark markings are smaller than the interspaces; underside yellowish with small dark markings. The keeled scales are in 25-27 rows.
Diamond-backed water snakes occur in and around lakes, ponds, marshes, swamps and larger streams and rivers, especially in low country. They give birth to 6-62 young.