Logan Martin Lake Hydrology
Logan Martin Lake starts at the discharge of H. Neely Henry Dam near Ohatchee, Al which is in Calhoun County)and extends in a southern direction to the Logan Martin Dam near Vincent, Al.(Located in St. Clair) The Coosa River is the primary water source for Logan Martin Lake, numerous smaller streams also flow into the lake. Prevailing flow is from the north to the south along a snake like course. The Coosa River begins in the Appalachian Mountains and its waters, and those of Logan Martin Lake, eventually wide up in the Mobile Bay and the Gulf of Mexico through the Alabama River and Mobile River. Logan Martin Lake basically still runs the coarse through its upper reaches. From the location of Lock 4 to the I-20 bridge, the river expands some what, but is still largely confined to the original course of the Coosa River and the immediate mouths of tributary streams rather than spreading over the floodplain like a typical reservoir. From the I-20 bridge near Riverside to the Dam, the lake expands to a width much greater than the original river channel, with large areas of open water and many medium to large sized sloughs, coves and creeks. The maximum depth at the dam is 69 feet.
