Environmental Sedimentology of Bishnumati River, Northwest Kathmandu Basin, Central Nepal

Abstract

The Bishnumati River, a sixth-order perennial river with a humid climate, has been under serious degradation due to both natural and man-made disturbances. One of the prominent problems is surface water pollution, which has resulted from the direct disposal of sewer effluents, disposal of solid waste, and illegal settlements on riverbanks. The overall state of the river is deplorable, with major contributing factors being uncontrolled wastewater discharge, indiscriminate dumping of wastes, unauthorized encroachment, sand quarrying, and unsustainable urban expansion. Human activities along the riverbanks have significantly affected the environmental features, with a heightened rate in the deterioration of the river. These issues can be resolved with prompt and effective governmental action, such as the imposition of strict wastewater treatment regulations, sustainable waste collection and disposal systems, and illegal settlements removal. Consequences of these measures are crucial to the rehabilitation and protection of the Bishnumati River, its ecological balance maintenance, and prevention of further degradation.