3. WHY DAMS?
Water is essential for sustaining all life.
Population movement and increase require water
year round in remote areas.
Water collection and utilization is important.
Ability to sustain dough and dry situations.
4. WHAT IS DAM?
A structure to contain water.
A solid barrier constructed at a suitable location
across a river valley.
Has mechanically engineered structure to direct and
control flow of water and storage.
5. TYPES OF DAMS
Gravity Dam Arch Dam
Buttress Dam Embankment Dam
9. DAMS STATISTICS
By the end of the 20th century , there were 45,000 large
dams built in 150 countries .
International Commission on Large Dams (ICOLD)
Displacement of 4 million people annually due to dams.
Approximately 1,700 dams are being built , at the cost of
about 50 million dollars per year.
19% of electricity from hydro power-more than 50% in 63
countries.
12% of all dams have a water supply function.
75 countries have dams for flood control.
Dam supports 30-40% of irrigated area and 12-16% of
global food production.
World Commission on Dams (WCD)
16. CONCLUSION
Small dams should be built instead of large dams
Careful planning throughout the site selection ,
design and construction of dam is critical
Sociological impacts should be considered along with
the main objectives of water supply , power
generation and flood control
Economic incentives should be weighed against
sociological impacts
