Unwatering the Divide Cut of the Tennessee-Tombigbee Waterway: A major challenge to construction

Abstract

The construction of the Divide Cut of the Tennessee-Tombigbee Waterway required excavation of more than 150 million cubic yards of unconsolidated sand and clay To make this excavation required lowering the artesian groundwater table as much as 100 feet Lowering of the artesian head was accomplished with deep wells, while the gravity groundwater was removed by trenching Environmental considerations required predicting and monitoring the drawdown of groundwater in the area of the canal More than 1,000 piezometers were used to monitor construction excavation and the spread of the drawdown cone The 280-foot bottom width canal was successfully completed ahead of schedule with the groundwater safely controlled through permanent relief wells