Correct Answer - Option 4 : To generate the electricity power from water
Any hydraulic structure which supplies water to the off taking canal. Diversion head-work provides an obstruction across a river so that the water level is raised and water is diverted to the channel at the required level. The increased water level helps the flow of water by gravity and results in increasing the commanded area and reducing the water fluctuations in the river.
Functions of a Headwork:
- A headwork raises the water level in the river
- It regulates the intake of water into the canal
- It also controls the entry of silt into the canal
- A headwork can also store water for small periods of time
- Reduces fluctuations in the level of supply in the river
Types of Canal Headwork:
1). Storage Headwork:
When a dam is constructed across a river to form a storage reservoir, it is known as storage head work. It stores water during the period of excess supplies in the river and releases it when demand overtakes the available supplies.
2). Diversion Headwork:
When a weir or barrage is constructed across a river to raise the water level and to divert the water to the canal, then it is known as diversion head work. The flow in the canal is controlled by the canal head regulator.