Also within a few minutes of Charlotte is the new US National Whitewater Center, an eye-popping man-made whitewater park http://(www.usnwc.org).
If whitewater is your thing, it's available regionally. About a 4-hour drive west is the family-friendly Nantahala. A little further in TN is the Ocoee. Roughly the same distance north in WV you can reach the more challenging New River or in the fall the bone-jarring Gauley.
There are many other nice lakes 1-3 hours away and beautiful canoing nearby on the Catawba or about 2.5 hour away at New River State Park.