Found this outside on patio in northern Virginia, Ashburn area, September 2018. It's about 12 inches. Is it a water snake or rattlesnake?
It looks like an Eastern Hognose Snake, which is characterized by an upturned nose and high likelihood of playing dead.
These are described as variable in coloration:
"Two color phases are common in Virginia: (1) a patterned phase (79.6%, n = 98), characterized by a series of 19-27 (average = 23.2 ± 2.4, n = 12) black or dark-brown blotches along middorsal line, with alternating black spots on sides; body color consists of varying combinations of gray, tan, pink, yellow, orange, and red; venter of body and tail immaculate cream to dark gray;"
If you replace the tan in this image (www.virginiaherpetologicalsociety.com) with gray in yours, I think the pattern match and overall body form are very similar: