Kuhrang III Dam Project

Project Purpose / Layout

The purpose of the dam is to store the flood flow of the Birgan River and transfer it to the drainage basin of the Zayandeh Roud River through Kuhrang tunnel # 3.

Geographic Location

The dam is being built on the Birlan River in Kuhrang valley. The study area of the project is situated 120-km southwest of city of Shahr-e-Kord in Chahar Mohal Bakhtiari province.

Project History

The Birgan River water had been planned to convey to the Zayandeh Roud River since Safavids. The first and second water conveyances were in 1954 and 1985 respectively. The Kuhrang III dam and tunnel were first studied by Zayandab Company and then Mahab Ghodss Consulting Engineering Company began studying and supervising the construction of the project area in 2003.

Specific Characteristics of Project

Concrete double curvature arch dam and 350x106 m3 reservoir

Technical Specifications of Project

Dam

Dam type

Concrete double curvature arch dam

Dam height above foundation (m)

135

Dam crest length (m)

235

Dam crest width (m)

8

Dam body volume (m3)

300 x 103

Total reservoir volume (m3)

384 x 106

Active reservoir volume (m3)

300 x 106

Mean annual inflow (m3/s)

275

Spillway

Type of spillway

Free spillway (4 bays)

Flood discharge capacity (m3/s)

1738

Powerhouse

Powerhouse type

-

Number of units

-

Design head (m)

-

Installation capacity (MW)

-

Mean annual generation (GWH)

-

Diversion System

Type of diversion system

Tunnel      

Number of diversion tunnels

1

Length of diversion system (m)

560

Diameter of diversion system (m)

6

Discharge capacity of diversion system (m3/s)

380

Power Tunnel 

Length of power tunnel (m)

-

Diameter of power tunnel (m)

-

Water Conveyance Tunnel

Length of water supply tunnel (m)

23409

Diameter of water supply tunnel (m)

4.1

Bottom Outlet

Discharge capacity of bottom outlet (m3/s)

222

Intakes

Discharge capacity of irrigation intake (m3/s)

-

Discharge capacity of drinking water intake (m3/s)

-

Discharge capacity of power intake (m3/s)

-

Relocation Roads & Access Roads

Length of relocation roads (km)