Conservation and Management of Rivers in India: Case-study of the River Yamuna

The River Yamuna, originating in the Himalayas, is the largest tributary of the River Ganga (Ganges) into which it flows at Allahabad. Its drainage basin covers about 42% of the Ganga River basin and about 11% of India's total land area. The area of the Yamuna drainage basin is densely populated and under intensive agriculture, while industrial activity is also rapidly growing in it. Climatically, a large part of the basin is semi-arid, and the river-flow depends upon highly erratic monsoonal rains. Therefore, the River and its tributaries have been regulated for over a century by dams and barrages for domestic water-supply and irrigation.Besides increased flow-regulation, the River's system has been under increasing anthropogenic stress from discharge of—mostly untreated—domestic and industrial wastewaters, and from other activities in the basin. River Yamuna is severely polluted by domestic and industrial effluents especially from Delhi down to Agra. Water extraction and consequently low flow has affected the selfpurification capacity of the River. The greater inflow of River Chambal helps River Yamuna to recover to some extent after their confluence near Etawah.Studies of water quality and biota of the River Yamuna along its course during the past 30 years show rapid deterioration of water-quality, loss of fisheries, and significant changes in the biotic communities. In the manner of River Yamuna, its tributaries have also become increasingly polluted during the same period. There has, however, been little attention paid to the management of the River system and conservation of its resources, except for some efforts at the treatment of sewage effluents but emphasizing only water-quality. Ignoring the river-flood-plain interactions which play significant roles in the ecology of a river, most of the floodplain has been reclaimed by constructing high levees.We emphasize that the Yamuna River basin should be treated as one ecocomplex in developing appropriate management strategies, and that the conservation of waterquality and biota can be achieved through protection and better management of floodplains than has been practised to date.