Last I knew, Smith was released during the day and pumped back up at night to get power when needed ,(read expensive)...a 2 lake system. So, I'm guessing power demand affects it too. Looked at this site, and it is down 5'...
https://www.smithmtn.com/lake-levels/
...but it's been lower.
Appalachian Power used to have a great visitor center at the dam with large models that explain their system. It's out of the way, but really worth it. Staffed by volunteers too. Been years since I was down that way...hope it's still in operation.