The Apalachicola-Chattahoochee-Flint River Basin originates in northeast Georgia, crosses the Georgia-Alabama border into central Alabama, and follows the state line south until it terminates in Apalachicola Bay, Florida. The basin covers 60 counties in Georgia, 10 counties in Alabama, and 8 counties in Florida. Extending a distance of approximately 385 miles, the basin drains 19,600 square miles.
The ACF River System is linked to our nation's vast inland navigation systems through the Gulf Intracoastal Waterway. The Apalachicola, Chattahoochee, and Flint River System consists of a channel 9-feet deep and 100-feet wide from the mouth of the Apalachicola River to the head of navigation at Columbus, GA, for the Chattahoochee River and at Bainbridge, GA, for the Flint River.
The total waterway distance is 290 miles with a lift of 190 feet accomplished by 3 locks and dams. The system also provides hydro-electric power, water supply, water quality, flood control, and recreational opportunities.
The USACE Water Management Section of the Mobile District operates five federal reservoir projects: Buford Dam (Lake Lanier), West Point Dam, Walter F. George Lock and Dam, George W. Andrews Lock and Dam, and Jim Woodruff Lock and Dam (Lake Seminole) as components of the ACF system.
These are multi-purpose projects for which operations have been congressionally authorized either through the original project authorizations, or by subsequent congressional authorizations that apply generally to all USACE reservoir projects. The reservoir projects are operated in a balanced manner within the system to support all authorized project purposes and benefits within the ACF system to the extent practicable.
USACE does not prioritize the project purposes but does use action zones that have been defined for each of the major storage reservoirs in the ACF system—Lake Lanier, West Point Lake, and Walter F. George Lake. These action zones, which are outlined in the 1989 Draft Master Water Control Plan, are used to determine minimum hydropower generation and maximum navigation releases from conservation storage in the lakes while balancing the lake levels in a system-wide approach.
The guidelines in the Draft Water Control Plan reduce the amount of water available for augmenting navigation flows and other project purposes as drought conditions intensify in the basin. Ultimately, during times of drought, operations in support of navigation and hydropower may become very limited and recreation will be affected.
The strategy of operating the projects also calls for water to be taken first from storage in the lower lakes on the system and gradually pulling water from the upper lakes over time. Thus, Walter F. George, which contains most of the storage on the lower system because Lake Seminole does not have much storage, will be the first lake to be affected by operations on the system during periods of low water. If conditions remain dry, water will also be pulled from West Point Lake and eventually Lake Lanier. This is all done in accordance with the action zones and guidelines in the Water Control Manual, which attempts to equitably balance the lakes in the system. Varying hydrologic conditions throughout the ACF River Basin may result in the lakes getting out of balance; but, eventually, they will be brought back into balance according to the manual.