You can find a sanitary dump station for RVs at Fort Gordon. They have both potable and non-potable rinse water available. To get there, take I-20 and then go north on US221 for about 9 miles. After that, turn left on Hwy. 104 and continue for about 4.75 miles. Stay to the right at Hwy. 47 and after half a mile, turn right onto Pike Avenue. This road will lead you to the campground where the dump station is located.