No, you must be part of a party with a campsite reservation to be allowed access to the campground. With that said, I'd recommend Lower Overlook Park for your activity. The park is just across the dam (only a few minutes from the campground), parking is free and there are picnic tables, grills and restrooms. While there's no beach, the park is peninsula, surrounded on three sides by water. Hopefully this answer is helpful.
Not at this campground. There are other places around sawnee that you can picnic that are very close.
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