How can human activities effect a river?

Answer 1

• Drying up in summer: - Most of the rivers of the State go dry during summer months (January to May), because of the rampant deforestation at the sources of most rivers. Previously, the trees and plants of these areas used to help to absorb and conserve the rain water in the soil for the post monsoon periods. It was this stored water that kept the rivers alive during the summer months. Destruction of forests has also resulted in increased levels of soil erosion, which in turn has raised the floor levels of dam reservoirs, thus reducing their capacity.

• Wet land filling- The above adverse development was aggravated by large-scale conversion of paddy and other types of wetlands for non-agricultural purposes. This reduced the recharging of ground water and the subsurface flow to rivers, thus accelerating the drying up of rivers.

• Sand mining:- The construction boom, fueled by the inflow of remittances from non-resident Indians and the inherent nature of people to construct ostentatious residential buildings, leads to indiscriminate mining of sand from rivers. This has pushed the water table down, reduced the water holding capacity and adversely affected the diversity of life forms thriving in the riverine eco system.

• Large Dams:- The large dams across the rivers, often several of them along the course of the same river, have adversely affected the flow pattern, extent and nature of sediment formation and deposition, riverine biodiversity, the quality of water.

• Deepening of land along the river banks:- The land along the river banks are often deepened to support manufacture of bricks. This is also a result of the construction boom arising from the rapid urbanization. The adverse results are a further lowering of water table of the rivers and the weakening of river banks.

• Encroachment:-The encroachment of river banks by unauthorized settlers, poses a serious threat to the health of the rivers in several ways.

• Pollution:- The rivers of the state are severely polluted. Domestic and urban wastes are a major source. Industrial wastes and wastes of modern agriculture (chemical fertilizers and pesticides) add to the problem.
• Dumping - Discarding materials into a river. Any chemical, such as car oil or antifreeze, poured down a

storm drain will flow directly into the river. Many people don't realize this water isn't "cleaned" before it runs

• right into a natural waterway.

Answer 2

We can cut down trees growing around the river, divert rivers etc...