The Kollidam basin mostly serves the ever-increasing sand needs for builders in and around the towns and therefore is the most exploited resources of the river basins in the State. The background note says that mining operations, both legal and illegal, have been noticed in a number of places and the norm regarding the depth of the mine is often flouted. Irrigation and drinking water supply are the major casualties. Besides lorries, that are overloaded with sand damages village roads. In some places, houses are found to have developed cracks. The Kollidam River, with its banks eroded as a result of illegal sand mining. The basin is one of the most affected river basins in Tamil Nadu. Deposed that the extensive illegal mining for silicon sand had resulted in depletion of groundwater and consequently affected agriculture in the village. With drain canals blocked, agricultural lands were getting flooded in several places. The degradation of river ecosystems is directly linked to development process. Indeed, no one can remain aloof from the issues related to environmental degradation of rivers. Among the various kinds of human interventions, indiscriminate mining for construction grade sand from the active channels and floodplains is the major cause for the degradation of rivers. Although the sand extraction is a destructive activity as far as river ecosystem is encamped, a proper assessment of its impact on various environmental components of the system is often difficult as many of the adverse effects are surfaced only after a long period of time.
