Lake Marion, Lake Moultrie and the 6-1/2 mile Diversion Canal make up the Santee Cooper Lake System. Lake Marion is 110,600 acres and Lake Moultrie is 60,400 acres. These lakes were created by the South Carolina Public Service Authority between 1939 and 1942. This hydroelectric project became known as Santee Cooper because of the two river systems the project connected.

The lakes vary from extremely shallow swamps to large open areas with depths of over 30 feet. There is a marked channel system in both lakes for navigation. The marked channel in Lake Marion extends from the Wyboo Area Dam to the Diversion Channel and Santee State Park close to the I-95 exchange. The channel is free of stumps and trees and is the most navigable route. Lake Moultrie is smaller and easier to navigate. It is very open and is up to 14 miles wide. A marked channel exists between the Diversion Canal and Pinopolis Dam. The Pinopolis Lock is open daily from 1/2 hour after dawn until 1/2 hour before dusk all year round.

These are world class fishing lakes with shallow swamps, black water ponds, thousands of tree stumps and live cypress trees, as well as large open areas of water. These lakes do not ice in winter and have produced record game fish, including world record Channel Catfish (58) lbs.) and Arkansas Blue Catfish (109.4 lbs.).

The Santee Cooper project creates a route for inland navigation from Columbia to Charleston. This 122 mile system provides a clearly defined navigable waterway.