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Diversion Head Works
Diversion
head works are essentially hydraulic structures built across rivers or streams
to raise the water level and divert the desired amount of water in a specific
direction, usually into a canal system. Their primary objective is to ensure a
consistent and controlled water supply for downstream usage.
Key Components of Diversion
Head Works
1. Weir or Barrage:
This is a low-height dam-like
structure built across the river to raise the water level. While weirs are
solid obstruction to water flow, barrages consist of a series of gates that can
be raised or lowered.
2. Fish Ladder:
Also known as a fishway, this
structure allows fish to migrate upstream of a weir or barrage, ensuring their
natural life cycle is not disrupted.
3. Divide Wall or Nose:
Positioned between the weir and
canal head regulator, it helps in bifurcating the flow – one towards the canal
and the other downstream.
4. Canal Head Regulator:
This is a gate-controlled
structure at the canal's head, managing the intake of water from the river to
the canal system.
5. Silt Excluders and Silt
Ejectors:
These devices prevent excessive
sedimentation (silt) from entering the canal, which could otherwise reduce its
carrying capacity.
6. Afflux Bund and Marginal
Bund:
Bunds or embankments constructed
to protect the adjoining areas from submergence due to raised water levels.
Importance of Diversion Head
Works
1. Controlled Irrigation:
By diverting river water to
canals, diversion head works facilitate controlled irrigation of vast
agricultural lands, ensuring consistent crop yields.
2. Flood Management:
These structures can reduce the
intensity of floods by diverting and managing excessive river flows.
3. Sediment Control:
With features designed to reduce
sediment intake, they ensure smoother flow in canals and reduce maintenance
costs.
4. River Navigation:
By maintaining desired water
depths, they support inland water transport and navigation.
Conclusion
Diversion
head works, with their intricate design and multipurpose utility, symbolize
human ingenuity in water resource management. By channeling waters effectively,
they not only sustain agricultural landscapes but also act as guardians against
floods and excessive sedimentation, striking a balance between man-made
infrastructure and natural ecosystems.