I have black snakes living in my garage. The garage is detached so I don't mind if they kill the mice so I let them be, usually. The last one I saw was about 6 feet long and about 2-3 inches in diameter. A bit scary but they don't seem much interested in people. But what it has done is make me worry about snakes. I am sure their are copperheads around I just have never seen one really don't wish to. I had a bag of wood clippings in the garageI was going to use for mulch. When I emptied the bags there were 13 snake eggs in the bag, all hatched.
One time I was returning from work and it was midnight. I cut through the yard and saw a "hose" laying in the yard. I put my foot on it wondering why a "hose" was laying in the yard. i later changed my undies when I realized it wasn't a "hose."