Skip to main content
Feb 26, 2016 / Haseeb Jamal -

5 Travel Myths You Need to Stop Believing Right Now

Feb 26, 2016 / Haseeb Jamal -

Canal Comes Alive with Lighted Boat Parade.

Headrace Tunnels - Definition, Uses and Types of Headrace Tunnels


There are different definitions for headrace tunnels (HRT) used in different scenarios. “Headrace tunnel takes water from connecting channels and convey it to the fore bay or directly to the penstock provided with surge shaft” depending upon the project and site requirements some times also known as power tunnels. Or

“A tunnel provided between De-silting chamber or Fore-bay to the Surge Shaft” or “A structure that carries water from intake to the power house for power generation”

Tunnels are very important components of any type of hydropower project and can be very useful in long run. Now day’s highly sophisticated machines are used for tunneling such as TBM (Tunnel Boring Machine) which can accomplish the work in months which may takes even years to be completed using manual procedures.

Headrace Tunnel
Headrace Tunnels

Headrace tunnels are very useful if the topography is not favorable for gravity channels such as irregular terrain, heavy vegetation, long route, social issues etc.

Uses of Headrace Tunnels

Tunnels are used for different purposes such as:

  • For pedestrians
  • For Rails
  • For Vehicles
  • For Water etc

Here we will be focusing on its use for water i.e water tunnels (Headrace tunnels)

Types of Headrace Tunnels

Types on the basis of flow

On the basis of flow headrace tunnels can be divided into the following main types

  • Pressure flow tunnels
  • Gravity flow tunnels

The two types will be discussed in details with design examples

Types on the basis of shape

On the basis of shape tunnels can be divided in to the following main types

  • Semicircular
  • Circular
  • Elliptical
  • Horseshoe and
  • Square with an arched ceiling

Now a days horseshoe tunnels are widely used for hydropower project because of its efficiency and easy construction.

Subscribe to our Newsletter

Stay informed - subscribe to our newsletter.
The subscriber's email address.

Search AboutCivil

Related Civil-Engg. Content