Head Race Tunnel (HRT) takes water from connecting channels and conveys it to the forebay or directly to the penstock furnished with Surge shaft relying upon the project and design requirements and is on occasion additionally called Power tunnels. It is the shape that consists of water from Intake to the Power House for Power technology.
Types of Head Race Tunnel (HRT):
- On the basis of flow:
(i) Pressure flow tunnel
(ii) Gravity flow tunnel
- On the basis of shapes:
(v) Square with an arched ceiling
LAYOUT OF HRT
The Head Race of the tunnel it depends on the project we create for example The head Race tunnel of the Singoli-Bhatwari Hydroelectric project (Uttarakhand, Chamoli) is 11.256 km long. The tunnel has a finished dia. of 4.9 m and is concrete covered and metal covered with various thicknesses depending on the geological condition of rock. The excavated phase of the top Race tunnel has been kept as D-formed with a backside width of 5 m. The excavated diameter of the tunnel is 6m. The excavation of the tunnel has been performed thru five construction ADITs on the right bank, every D- shaped with lengths varying from 163m to 546m. The length of the tunnel among the ADITs varies from 680 m to 5635 m.