I.  Main Civil Works/Packages Including Hydro-Mechanical (HM) Works


Contract Package # C-1 :-Construction of Diversion Tunnel, Dam, Intake and Desilting Arrangement including Hydro-Mechanical works and Highway Tunnel

The construction work of Diversion Tunnel, Dam, Intake and Desilting Arrangement including Hydro-Mechanical works and Highway Tunnel was awarded to M/s Jaiprakash Associates Ltd. on June 26, 2011.

The Contract Package C-1 consists of following components:

  • 1 No. Diversion Tunnel of 12 m dia., 877.46 m length & 1118 Cumec. Design Discharge
  • Concrete Gravity Dam of 91 m height & 223.8 m length
  • U/s Coffer Dam of 168.75 m length & 22 m height
  • D/s Coffer Dam of 102.02 m length & 13.5 m height
  • Chute with Gates type Auxiliary Spillway with 1 No. gate
  • Sluice Spillway with 7 Nos. Gate, each of  8 m x 13.20 m
  • 4 Nos. Intake Tunnels each of 6.4 m dia. & total length of 1926.78 m
  • 4 Nos. underground Desilting Chambers each of 420 m (L) x 17/19 m (W) x 24.74 m (H)
  • Silt Flushing Tunnel(D-shaped) of size 3.6 m (W) x 2.96 m (H) to 8.6 m (W) x4.675 m (H), 495 m length
  • Highway Tunnel of 11 m dia., 1522 m length

Special Features / Uniqueness of the Package

  • Diversion Tunnels (with 12 M dia) constructed is the largest in the sub-continent.
  • Desilting Chambers are the biggest in size in the country.
  • First ever Highway Tunnel (1.5 KM) constructed in Bhutan on the National Highway.