Some helpful Lake Lanier links for you:

Army Corps of Engineers: https://www.sam.usace.army.mil/Missions/CivilWorks/Recreation/LakeSidneyLanier.aspx

Department of Natural Resources DNR: https://www.gadnr.org/

Lanier Islands Resort: https://www.lanierislands.com/lake_resort_georgia/

Marinas on Lake Lanier: https://lakelanier.com/directory/marinas/

Lake Lanier Levels: https://water.sam.usace.army.mil/gage/acf/prob1.txt