Pumped storage hydroelectricity is one of the most efficient methods for
providing balance in power grid to supply high peak demands. The Siah Bishe
Pumped-storage Hydroelectric Power Project and its dams are located in
Mazandaran Province, over Chaloos River, 125 km north of Tehran. It is also
adjacent to Chaloos Road, 10 km north of Kandovan Tunnel (75 km from Chaloos
City). It has an installed capacity of 1000 MW. In comparison to country’s other
projects, which are in the primary stages or under construction, this project is
unique on behalf of operation of pumped storage and type of dams. This project
consists of building the first pumped storage plant and the first Concrete Face
Rockfill Dam (CFRD) in the country. The project is basically intended to supply
electricity at times of peak demand and create a safe consumer for the entire
Iran power grid during the hours of low electrical demand.
Decline in the annual costs of depreciation of thermal power plants up to $19
M, creation of an entertaining and touristic environment for foreign and
domestic tourists and employment in the project area during the period of its
execution and operation are some of the other objectives of the present project.
In a tender held on 2003, the Siah Bishe Project was awarded to selected
contractors, within the framework of two design-build contracts. On Aug. 3,
2003, Beta, Soils Engineering Services (SES) and Kayson Company entered into a
joint venture agreement, with the last-named party as the leader of the
consortium, to carry out contract A which includes designing and building of the
body of two concrete-face dams as well as the main parts of the headrace tunnels
and related installations. In June 2010, construction of the complementary
operations of the two dams was notified to the parties.
The design of CFRD
dams and the related structures was done by a team of Iranian designers and the
Swedish Pöyry company (Electrowatt).
Scope of Work
The second phase of the project and the joint venture’s sphere of work
involve detailed design, construction of two Concrete Face Rockfill Dams (CFRD),
the concrete-face upper and lower dams, and completion of headrace tunnels. The
power plant’s up and down pumped-storage reservoirs respectively have a storage
volume of 4.3 and 6.9 million cubic meters, stand 82.5 & 102 meters high and 436
& 332 meters across the crest.
Each of the two headrace tunnels which link up the two dams is 2000 meters
long, with approximate excavation diameter of 7m and final diameter of 5.7m. The
tunnels will have a 40 cm thick concrete lining.
- Excavation in Rocky Ground Conditions: 2,100,000 m3
- Excavation in Normal Ground Conditions: 4,443,000 m3
- Rockfill: 4.9 million m3
- Tunnel and Gallery Excavation: 190,000 m3
- Shotcrete: 27,000 m3
- Anchor Bars (Rock bolts): 260,000 m
- Grout Holes: 200,000 m
- Reinforcement: 19,000 t
- Formwork, F1 Type: 200,000 m2
- Movable Formwork: 75,000 m2
- Concrete Placement: 175,000 m3
- Length of Each Headrace Tunnel: Approximately 2,000 m