I could suggest Johnson Creek on Lake of the Pones in NE Texas. Lots of green and trees. The corp of engineers manages several very nice camp grounds around the lake. Most sites have water front access and are full generally around the big holidays. They all have boat ramps and beach areas.
I live on the lake just across the bay from the Johnson Creek campsite. Very beautiful, clean, safe, and low cost. There are a number of smaller towns near and Longview is about 30 miles away (pop about 80,000).
you should be able to find out much more online. The lake is about 20 miles lon