Northern Water Snake

I agree with plain-bellied watersnake, with this being the subspecies blotched water snake.

It's a Plain-bellied, not Northern, Watersnake.

Thank you. I didn't mess with him too much. Just let him go on his way.

Judging by the picture I believe it is a Northern Water Snake. They are also rather aggressive compared to many other snakes of (at least Eastern) USA.