|Location||Baldwin / Hancock / Putnam counties, Georgia, USA|
|Primary inflows||Oconee River (see article)|
|Primary outflows||Oconee River|
|Basin countries||United States|
|Surface area||15,330 acres (6,200 ha)|
|Max. depth||90 ft (27 m)|
|Shore length1||417 mi (671 km)|
|Surface elevation||340 ft (100 m)|
1 Shore length is not a well-defined measure.
Located in the central region of Georgia, on the Oconee River, Lake Sinclair stretches through the counties of Baldwin, Hancock, and Putnam, Lake Sinclair was created in 1953. With approximately 417 miles (671 km) of scenic shoreline, winding coves and inlets as well as several vast stretches of open water, Lake Sinclair has plenty to offer for recreation and boating pleasure. The lake is made up of a 15,330-acre (6,200 ha) area of water and provides both electricity and recreation. Milledgeville, Georgia, is the largest city on Lake Sinclair, though most of the lake is located in Putnam County 
Lake Sinclair is largely used by lake residents and people who live and house their boats, watercraft and RVs on the lake – thus access is as easy as lowering their watercraft into the water. For day or weekend visitors, Georgia Power provides two public boat ramps for public access to water recreation. There are also marinas and boat storage areas located on the lake. There are other areas of access to the lake including Oconee Springs Park and several "secret" public access areas. Lake Sinclair is the site of several fishing tournaments - both local and national - and attracts fisherpersons of various skill levels and interest. Visitors find fall and winter fishing at Lake Sinclair a special treat due to the mild climate and activity. There is also a popular fishing area below the dam near Milledgeville. Several recreation areas, such as Oconee Springs Park and Rocky Creek Park, provide day-use facilities that include picnic tables, grills, boat ramp and a small beach. There is camping and even cabin rentals provided at Oconee Springs Park, but not Rocky Creek Park.
Lake Sinclair was created in 1954 when the waters of the Oconee river were dammed to create a 45,000-kilowatt hydroelectric generating station. Development of this lake as a recreational area began through a planned cooperative program. Participants included the Oconee Area Planning and Development Commission, the U.S. Forest Service, The Georgia Game and Fish Commission, Georgia Power Company and several independent businesses.
Lake Sinclair is fed by several creeks and rivers, including Beaver Dam, Crooked, Rooty, Sandy Run, Shoulder Bone, Potato, Island, Rocky, Nancy Branch, Reedy Branch, and Little River. The lake covers over 15,000 acres (6,100 ha) and has more than 400 miles (600 km) of shoreline with a maximum depth of 90 feet.
In 1979 Lake Oconee was created with the completion of Wallace Dam, which is a pumped-storage reservoir for Lake Sinclair. What this means is that the water is pumped from Lake Sinclair into Lake Oconee, its dam-sharing lake. It is then released through Wallace Dam back into Lake Sinclair - thus generating electricity. It's quite fascinating to newcomers and you can tell which stage of the operation the process is in by watching the current on Lake Sinclair. Either stop your watercraft and watch the shoreline, or if you are on shore, fix your eye on a watercraft or object in the lake. It will move in either direction depending on the stage of pumping/dam operation. The net effect of the power generation process is an approximate 2-foot (0.61 m) drop or rise in Lake Sinclair's water level. This drop or rise is minimal and only affects boaters located in very shallow water. Lake Sinclair offers year-round, consistent water levels.
The Sinclair dam is approximately 105 feet (32 m) high and 3,000 feet (910 m) long