It's open to the public but you have to get a screening done at any of the entrances that you go into Fort Jackson through. It usually takes about 10 to 20 minutes depending on how many people are there but not much longer. Be prepared to pay for your water park tickets there at the booth just for proof of authenticity of the destination you claim to be going to. Also just saying I'm a long-time fan of this Waterpark but the last time I visited a month ago it was an atrocious conditions. I don't know what you can do about that, but heads up.
Unsure if it is open to people without military affiliations i.e. someone who is a vet or family of an active duty soldier. I dont believe it is atrocious in the slightest. It is small so your expectations should suit your destination
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