15) “Dam and Classification of Dams”
(Date of Publication = 18th April, 2014)
Dam
A dam is a barrier built across a stream, river or estuary to hold and control the flow of water for such uses as drinking water supplies, irrigation, flood control and hydropower generation etc. 
Classification of dams
Dams are classified on several aspects, some of the important aspects are as follow:
1) Based on Hydraulic Design
Following are the classification of dams based on Hydraulic Design
- Over flow dams (e.g. concrete dams)
- Non over flow dams (e.g. embankment dams)
2) Based on Structural Design
Following are the classification of dams based on Structural Design
- Gravity dams
- Arch dams
- Buttress dams
3) Based on Usage of Dam
Following are the classification of dams based on Usage of Dams
- Storage dams
- Diversion dams
- Detention dams
4) Based on Construction Materials
Following are the classification of dams based on Construction Materials
- Concrete / Masonary dams
- Earthfill dams
- Rockfill dams
- Earthfill rockfill dams
- Concrete faced rockfill dams (CFRD)
5) Based on Capacity
Following are the classification of dams based on Capscity
- Small dams
- Medium dams
- Large dams
Largest Dam in the World
The Three Gorges is the largest in the world, as wide as the Golden Gate Bridge and twice as tall, capable of generating 18 gigawatts of hydro-electric power.
Ubaid Ahmad Mughal
Structural Engineer