Posted in Civil Engineering, Hydraulic Structure, Water Resources Engineering

Canal Head Regulator

Structure at the head of canal taking off from a reservoir may consist of nu ber of spans separated by piers and operated by gates.

Regulators are normally aligned at 90° to the weir. upto 10″ are considered preferable for smooth entry into canal. These are used for diversion of flow. Silt reduces carriage capacity of flow.

Types of regulators in canals

  1. Still pond regulation
  2. Open flow regulation
  3. Silt control devices

Still pond regulation:

  • Canal draws water from still pond
  • Water in excess of canal requirements is not allowed to escape under the sluice gates.
  • Velocity of water in the pocket is very much reduced; silt is deposited in the pocket
  • When the silt has a level about 1/2 to 1m below the crest level of Head Regulator, supply in the canal is shut off and sluice gates are opened to scour the deposited silt.

Canal Head Regulator

Head Regulator

Open flow regulation:

  • Sluice gates are opened and allow excess of the canal requirement
  • Top water passes into the canal
  • Bottom water maintain certain velocity in the pocket to keep the silt to remain in suspension
  • Canal is not closed for scouring the silt.

Silt control devices:

  • Silt control at head works
  • Entry of silt to canal can be controlled by Providing a divide wall to  Create a trap or pocket
  • Create scouring capacity of under sluices By concentrating the currents towards them
  • Paving the bottom the approach channel to reduce disturbance because due to disturbance sediment remains in suspension