The wash form the steam tugs was believed to wear away the bank side. It was the task of the TNC to maintain the riversides. The TNC turned to dredging the river to allow larger vessels, especially at the coal staithes, to move along the river unaided.
Dredging was used to create more depth to the river and allow ships easier passage. Between 1845 and 1900 upwards of 34 million tons of material had been removed by dredging of the bed of the river.