Many river valley projects have been started for the purpose of integrated economic and social development of the river basins.
Advantages of multipurpose projects :
(a) dams are built for irrigation.
(b) they generate electricity
(c) they provide water
(d) they help in industrial development
(e) they control floods
(f) they help in recreation and navigation
(g) they help in fish breeding.
Many benefits are obtained simultaneously. So they are called Multi-purpose projects.
Disadvantages of multipurpose projects :
(a) they affect the natural flow of rivers.
(b) this results in poor sediment flow and excessive sedimentation at the bottom of the reservoir
(c) it results in poorer habitats for aquatic life in the river.
(d) they submerge the existing vegetation and lead to soil decomposition
(e) it also causes a large-scale displacement of the local communities.
