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Source: https://erdc-library.erdc.dren.mil/jspui/ Jones Bluff Lock and Dam is proposed for construction on the Alabama River about 245 miles above its junction with the Tombigbee River to form the Mobile River in south central Alabama about 45 miles above Mobile Bay. The project, which will provide a navigable pool for 75 miles upstream to the mouth of the Coosa River, comprises a nonnavigable gated dam with eleven 50-ft-wide by 35-ft-high tainter gates, an 84- by 600-ft lock on the left bank with a maximum lift of 45 ft, and a four-unit powerhouse on the right bank with a maximum discharge capacity of 35,200 cfs. A 1:100-scale, fixed-bed model reproducing approximately 3.6 miles of the Alabama River was used to determine navigation conditions in the lock approaches, determine effects of powerhouse releases, and develop modifications required to provide satisfactory navigation conditions. In general, the results have indicated the following: Modification of the dredging for the upper approach channel and ports in the upper guard wall would be required to provide satisfactory navigation conditions in the upper approach to the lock. A large eddy extending into the lower lock approach would develop with power house flow and no flow through the spillway. Because of the eddy, tows would experience considerable difficulty in approaching the guide wall. The difficulties can be eliminated with a wall or dike extension to the lower guard wall. The danger of small boats being moved into the powerhouse tailrace can be minimized with a 200-ft wall between the powerhouse tailrace and stilling basin. The amount of rock excavation can be reduced appreciably without seriously affecting flow conditions downstream of the dam. |
