Multipurpose river valley project consists a dam or series of dames on a river or rivers for fulfill many
purposes like:
(a) irrigation
(b) electricity
(c) control flood
(d) check soil erosion
(e) inland navigation
(f) fisheries etc.

(I) The three major sources pf irrigation in India are –
(a) Canals
(b) Wells & tube wells
(c) Tanks
 (II) Tank irrigation
 (III) Because Southern States are mostly come under Deccan plateau
 which are not suitable for irrigation by canals

“Water scarcity” means shortage of water.

CAUSES: 
(a) Unequal distribution of rainfall
(b) Large & growing population
(c) Over exploitation of water
(d)Wastage of water by people 

Two Multipurpose project which are caused social movements –
(a) Narmada –Bachao Andolan
(b) Tehri-Dam Andolan
(c) Sardar Sarover Dam
-Large scale displacement of local communities
-Environment issues
-Demand for Rehabilitation facilities from Govt.

In Meghalaya, 200 years old system of tapping stream and spring water by using Bamboo –pipes.

People developed inundation channels to irrigate their fields were converted into rain storage structure in particularly western Rajasthan Jaisalmer called Khadins and Johads in other parts of its state.

People built division channels from rivers for irrigation to their field in western Himalaya is called Guls or kuls .

i)To safeguard ours from health hazards
ii) To ensure food scarcity
iii) To protect natural ecosystem