Very nice snake Justin - probably a big female and maybe already gravid. Your posts remind me of some of thrill I had catching northerns when your age. I remember a huge female that I stalked for a long time - stepping very slowly through a pond with just my head above water. When I finally got out to the log she was sunning on I could barely touch the bottom so I had to get almost directly under her and grab up and over the log. I did a rough measurement in the field - using my body as a measuring stick. When I got home and looked it up she was bigger than what Conant listed as the record!
I wish I had a resource like Kingsnake when I was your age. We really learned the hard way - through trial and error. Among the important lessons I learned the most important is simple: Don't bring home more than you can properly care for. My enthusiasm upon finding and catching often meant I brought stuff home I didn't have a lot of time for. I would have been much better off to just limit my self to a few rather than all as would of the snakes!
PS: The brown water below is a great looking snake too - let us know how it goes with that one. Watch out for mites, mouth flukes and other trouble. I once had a wild caught green that was friendly, even lethargic - but seemed to react aggressively to handling. It would eat but always regurgitated. She died after a few weeks. I performed an crude necropsy and found she had ingested a branchy twig that had lodged in her stomach.
Good luck with yours! Keep the pictures coming.