September 2004
As the Three Gorges Project on the Yangtze River has
successfully accomplished the key milestone of low stage operation
and is slated to complete in 2009, China is moving ahead with another
major hydropower development further upstream. In this development,
a series of high dams will be built on the Jinshajiang (the Golden
Sand River), starting just about 35 km above Yibin in Sichuan Province
(or 621 km above the Three Gorges Dam). Combined annual electric output
from the development is estimated at 2,504.73x108 kwh, about three
times the output from the Three Gorges Project. The development will
stretch over a reach of 1,255 km and include Xianjiaba, Xiloudu, Baihetan,
Wudongde, Guanyinyen, Pichang, Zili, Hongmenkou, and Hutuaoxia dams
(see map).
These dams will be an integral part of the Yangtze River basin development.
Electricity generated from these dams will support not only the power
thirsty Eastern/Middle China but also form the power base for the much-promoted
development of the Western Region. Main features of the dams are as
follows:
Dam |
Distance from Yibin
(km) |
Dam Height
(m) |
Gross Storage
(108 m3) |
Installed Capacity
(104 kw) |
Annual Output
(108 kwh) |
Xianjiaba |
35 |
160 |
54.1 |
600 |
264 |
Xiloudu |
184 |
278 |
126.7 |
1260 |
571.2 |
Baihetan |
382 |
265 |
193.8 |
996 |
519.7 |
Wudongde |
562 |
219 |
39.4 |
560 |
279.4 |
Guanyinyen |
817 |
- |
33.7 |
250 |
137.23 |
Pichang |
917 |
- |
88.2 |
270 |
136.5 |
Zili |
1014 |
- |
14.9 |
208 |
105.9 |
Hongmenkou |
1116 |
- |
67.2 |
375 |
187.9 |
Hutuaoxia |
1267 |
- |
181.6 |
600 |
302.9 |
Among the dam projects, Xianjiaba, Xiloudu, Baihetan and Wudonde
are included in Phase 1 for priority development. Feasibility studies
for
both Xiloudu and Xianjiaba have also been completed. Xiloudu dam
will be the first to proceed. Upon completion, it will be a concrete
arch
dam of 278 m high and 698 m wide at the top. The dam will involve
an excavation of 5.26 x106 m3 at the site and will take 6.656 x106
m3
of concrete to build. It will be equipped with 5 large side tunnels
and 15 sluiceways to convey the design discharge of 43,700 m3/s.
Two powerhouses will be built. Each will be installed with 9 units
of turbine/generator
of 700MW capacity each. It is estimated that 41,800 acres of farmland
and 10 township/villages will be flooded and about 39,500 people
will be resettled. Project cost was estimated at 445.73x108 RMB
based on
the 2001 price level.
When both are completed, Xiloudu and Xianjiaba will be jointly operated
to enhance their electric outputs. It is projected that Xiloudu will
increase annual electric output from the downstream Xianjiaba by
13.54x108 kwh and the Three Gorges/Gerzouba by 18.86x108 kwh. When
Xiloudu and
the Three Gorges are jointly operated, the required flood diversion
below the Three Gorges can be reduced by 25-40x108 m3 during major
flood events. In addition, most of the sediment from the Jingshajiang
will be intercepted by Xiloudu and thereby reduce sediment inflow
to the Three Gorges Reservoir. The Xiloudu Dam Project will take
108 months
to complete after the construction begins.
(Click on the map to download a PDF version)
