Rate of sedimentation in the Yamuna river around Delhi using the226Ra−210Pb method

For six sediment cores collected from Yamuna river (tributary of Ganges) around Delhi, rate of sedimentation was determined by the²²⁶Ra–²¹⁰Pb method. While an average rate of 42 mm/y is obtained, there are variations core to core. A clear-cut downstream increase in the rate, from 5 mm/y when the river enters Delhi, to 80 mm/y when it leaves Delhi, indicates solid waste contribution from the urban areas. The sediment flux of 4000 mg/cm²/y is not balanced by the calculated rate of erosion (40 tonnes/km²/y) in the river. Thus, much of the sediment flux is of local origin.