Yes. At Six Flags, it is permitted to bring in plastic water containers; however, out of an abundance of caution for the safety and comfort of our guests who depend on wheelchairs or their hands to move around the park, all water bottles must be empty but unopened at time of entry into the park. Guests who had already entered with their empty unopened container will need to exit and dispose of their contents. Hand sanitizer can be carried on-site not in container over 16 ounces.
Once you enter Six Flags with your water bottle (or hand sanitizer), please use appropriate bag if needed so that no spills happen on rides or by trash cans as there are some serious fines associated.