Help me identify snake please?

[qcrossley]

I was in Russia a few years ago (close to Saratov) I spent a week in a cabin on the volga. Every morning I washed myself in the river and said hi to a snake friend. I found out everyone else was scared of the snake and ran. I know nothing about snakes and live in Canada. Can anyone help me identify?

I don't have a picture but... It swam in the volga river. It was bright green kinda skinny between 1 and 2 feet long and smooth scales. I tried google and all I could find was the Russian rat snake, and it's not that. I'm interested to know what I saw and if it is venomous. Thanks folks.