I would suggest looking for property around a local river... you can usually find some within 300feet of the back (most states own the first 300feet from shoreline). The Angelina River in Jasper county has loads of "water front" for $2000 an acre. Its just finding something you want. I had looked into it for a extra BOL that had water front and boat access so i could fish. You could also build a old fashion water wheel to provide water to crops and live stock... just a thought
Most states do not own 300 feet inland from rivers on each side of the river.
Some states reserve a buffer zone, but nowhere near 300 feet. Here in Georgia for example much of the riverfront property, if not a national or state park, is privately owned. Same in Florida.
It's best people check the rules for each state individually and not assume it is all owned by government.