Ertan Dam


The Ertan Dam is an arch dam on the Yalong River, a tributary of the Yangtze River in Sichuan Province, in southwest China.
The dam has six hydroelectric generators, each with a generating capacity of 550 MW. The total generating capacity of the facility is 3,300 MW, one of the largest hydroelectric stations in China. The annual production is 17 TWh, and until December 5, 2006, it has produced over 100 TWh of electricity. Construction of the dam started in September 1991 and was completed on December 26, 1999. A total of of material was excavated during construction.
The Ertan Dam was designed by the China Hydropower Engineering Consulting Group Survey and Design Institute in Chengdu, and was constructed and is currently operated by Ertan Hydropower Development Company Limited, the owners of the dam. The company is invested by State Development and Investment Company and Sichuan Chuantou Energy Limited.

Design

The Ertan Dam is a high and long double-curvature arch dam. The dam withholds a normal reservoir of with a drainage area of and normal surface area of. The dam has four different ways to discharge water downstream. First, the dam's spillways which contain seven floodgates at the crest and two flood tunnels can discharge and respectively. The dam also contains 6 x middle outlets and four bottom outlets that can discharge and respectively. The dam's power station is located underground along with its transformer room which is in a separate cavern. Additionally, the power station is supported by an underground surge chamber as well.

Main Features

Source:
Project LocationOn the Yalong River, Sichuan province,
P. R. China
Project PurposeHydroelectric Power Generation
Years of Construction1987-1999
Construction of Main Dam
TypeDouble-curvature Arch Dam
Height240 m
Crest Length774.69 m
Construction of Power plant
Maximum gross head189 m
Installed Capacity6×550 MW
Power Conduits6 steel embedded in concrete
I.D.=9.0 m
Catchment and Reservoir
Catchment Area116,400 km2
Mean Annual Runoff1,670 m3/s
Reservoir Area at FSL101 km2
Storage at FSL5,800 million m3
Active Storage3,370 million m3
Discharge Capacity
Crest Outlet7 / 6,260 m3/s
Mid Level Outlet6 / 6,930 m3/s
Bottom Outlet4 / 2,084 m3/s
Flood Discharging2 / 7,400 m3/s
Project Developers
OwnerErtan Hydropower Development
Company, Ltd.
DesignerCHIDI,
now POWERCHINA Chengdu
ContractorEJV, SGEJV, GYBD
Main Equipment Suppliers
TurbinesGE Canada, Dongfang Electrical
Machinery Co, Ltd., Harbin Electric
Machinery Co, Ltd.
Generators & HV
Electrical
GE Canada, Dongfang Electrical
Machinery Co, Ltd., Harbin Electric
Machinery Co, Ltd.
Gates &
Hydromechanical
Jiajiang Hydraulic Machinery Works,
China Gezhouba Corporation,
Sinohydro Bureau No.8,