Environmental impact of multi purpose river valley projects?

Multipurpose river valley projects affect environment as they lead to the displacement of human, plants, animals, chiefly from small tribal communities; disrupt downstream fisheries; increase the risk of earthquakes; submerge forest land; increase the spread of insect-borne diseases; and threaten the fragile regional ecosystem through reducing, the flow of water from the rivers into the seas. These projects initially devastate human lives and biodiversity by inundating thousands of acres of forests and agricultural land. They degrade the fertile agricultural soils due to continuous irrigation (rather the seasonal irrigation which is dependent on the monsoon), and salinization, making the soil toxic to many plant species.

Further upstream, where the silt deposits have not yet become a problem, there's another problem. Landless people (predominantly tribal people and Dalits) have traditionally cultivated rice, fruit and vegetables on the rich, shallow silt banks the river leaves when it recedes in the dry months. Every now and then, the engineers manning the Bargi Dam (way upstream, near Jabalpur) release water from the reservoir without warning. Downstream, the water level in the river suddenly rises. Hundreds of families have had their crops washed away several times, leaving them with no livelihood

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