| Middle
Route Project (MRP) |
The middle Route Project (MRP) for South-to-North Water
Transfer will divert water, in the near future, from Danjiangkou
Reservoir on the Haijiang, a tributary of Changjiang River,
to Beijing City through Canals to be built along Funiu
and Taihang Mountains. In the far future, additional water
is due to be obtained from Three Gorges Reservoir or the
downstream of the dam on main Changjiang. The advantages
of this project lie mainly in good quality of the water
to be diverted, greater water-supply coverage available,
that water can be conveyed by gravity. The project will
be an important and basic facility for mitigating the
existing crisis of water resources in North China.
It has been already 40 years since the earlier stage study
on the MRP started in the early 1950s. In these years,
Changjiang Water Resources Commission, and other relative
provinces, cities, and departments have performed a lot
of investigation, plan, design and research works.
In January 1994, Ministry of Water Resources examined
and adopted "Feasibility Study Report on MRP for
South-to-North Water Transfer" made out by Changjiang
Water Resources Commission, and gave a proposal to build
this project to State Planning Commission. |
| Transferable
water quantity and scope of water supply
|
Based
on the completion of Danjiangkou Reservoir extending,
mean annual water quantity to be diverted will be 12.0~14.0
billion m3, and 6.2 billion m3
for the dry year (95% guarantee rate). The normal water
level of Danjiangkou Reservoir will be at 170.0 m. In
accordance with the development level in 2020, some
compensative projects will be built on the middle and
lower Hanjiang to ensure the development of industry
and agriculture, and the navigation and the environment
of the water exporting region.
MRP will supply water for Tang bai he Plain, middle
and western parts of Huang-Huai-Hai Plain, with a total
area of about 155,000 km2. Since the limitation
of water quantity in Hanjiang River, MRP can not meet
all the requirements of planned water supply areas,
only provide water for municipal and industrial use
in Beijing, Tianjing Municipalities, and Hebei, Henan,
Hubei Provinces, and give consideration to the agriculture
and other use of water in some partial areas.¡¡
|
| Layout
of MRP |
| The
main works of MRP will be composed of two major parts:
the engineering structures in water source region and
the water conveyance systems. The former includes Danjiangkou
Dam Extension Project on the Hanjiang and compensative
projects for its middle and lower reaches, and latter
includes the main trunk canal for diverting Hanjiang
and Tianjin main canal.
|
| 1.Engineertng
structures in water source region |
| (1)
Danjiangkou Dam Extension Project: |
Controlling 60% of the total drainage area of Hanjiang
River basin, Danjiangkou Reservoir has a mean annual natural
runoff of 40.85 billion m3. Taking account
of the development of upper reach, the reservoir was expected
to receive a mean annual inflow of 38.54 billion m3.
Based on the engineering scale already in place, it is
planned to continue to complete Danjiangkou Project to
its final scale, namely, to heighten the dam from its
existing crest elevation of 162 m up to176.6 m, with the
design storage level raised from 157 m to 170 m and the
total storage capacity consequently increased to 29.05
bi1lion m3. This means to gain, as against
the initial figures, an additional reservoir storage capacity
of 11.6 billion m3, an increased available
regulation storage capacity of 8.8 billion m3
and an extra flood control storage capacity of 3.3 billion
m3.
The normal storage water level of Danjiangkou Reservoir
will be at 170 m in its final configuration, with the
additional inundated area of 370 km2. In accordance
with the investigation in 1992, the main inundation indices
are as follows:
| Earth
excavation : |
300
thousand people |
| Houses: |
7.086
million m2 |
| Cultivated
land: |
0.01562
million ha |
|
| (2)
Compensative projects for middle and lower Hanjiang: |
|
To transfer water of more than 14 billion m3
in near future and avoid the available harmful effects
on water use for industry, agriculture and navigation
in the middle and 1ower Hanjiang Basin, it is required
to newly construct Xinglong or NianpanShan Hydraulic Project
on Hanjiang as part of the proposed main river canalization
project and a water compensating project diverting water
from Changjiang to Dongjianghe, and to modify or extend
part of the existing sluices and pumping stations, and
to build some additional navigation regulating works as
well. |
| 2.Water
conveyance systems |
| (1)
Main trunk canal |
Since
the limitation of the location of the existing canal head,
Fangcheng Saddle on the watershed between Changjiang and
Huaihe Rivers, the range of passing Huanghe, the line
of main trunk canal of MRP in the south of Hulanghe is
clear. As to the main trunk canal in the north of Huanghe,
two alternatives have been compared, utilizing the existing
river channels or excavating new canals. In accordance
with ensuring water quality and realizing of flowing by
gravity in the whole route, the later, excavating new
canals, was selected.
The main trunk canal, started at Taocha canal head, passing
the 8 km existing channel, northeast along the south side
of Funiu Mountain, going through NanYang City and crossing
Bait1e River, will enter Huaihe Basin by passing FangCheng
saddle on the watershed. Then, through Baofeng County,
Yuzhou County, and the west of Xinzheng, the main trunk
canal will cross Huanghe at Gubaizui in the northwest
of Zhengzhou City, the capital of Henan Province, and
extend on the North China Plain between the eastern Taihang
Mountain and the western Beijing-Guangzhou Railway, and
enter hilly area in Tangxian, and enter Beijing Metropolis
by crossing the northern Juma River ,and enter Beijing
urban district by crossing Yongding River, and terminate
at Yuyuan Pool. The total length of the trunk canal is
1273.72 km.
Tianjin main canal is 140.82 km in total length, from
the diversion spot on the main trunk canal in the north
of Xiheishan in Xushui County, Hebei Province, to Xihe
Sluice of Tianjin.
The design water level at the head of main trunk canal
is 147.38 m, and that at termination is 48.57 m. The water
diverted can now by gravity along the whole main trunk
canal.
The longitudinal gradient of the canal is 1/25000 for
the sections in the south of Huanghe and 1/30000-1/15000
for those in the north of Huanghe. For the purpose of
seepage control and roughness-reducing, the whole canal
will be full section lined all along the route with concrete,
cement-treated soil, shotcrete facing and the like in
accordance with the foundation conditions.
The design now for the canal is progressively reduced
from the south to the north, with water depth decreased
from 9.5 m to 3.5 m, and bottom width changed in the range
of 56.7 m.
The engineering geologic conditions and major geologic
problems along the main trunk canal have been mainly made
clear. As for some local engineering geologic troubles
relative to bentonite and loess, such as canal slope stability,
shock-induced liquefaction failure of sandy soils, earthquake
resistance in high earthquake intensity region, subsiding
of underlying coal and mined hollow zones, they all can
be readily solved and treated by adopting corresponding
measures.
Linking up four major river valleys, Changjiang, Huaihe,
Huanghe and Haihe, the main trunk canal ( including the
Tianjin main canal ) will have to run across 205 rivers,
medium or small, each covering a drainage area of over
20 km2, inclusive of the main Huanghe, and
42 railways. It is thus required to build, on the main
trunk canal, various structures, large-or small-size,
totalling 1774, such as regulating, diversion and tailrace
structures as well as tunnels and closed conduits, including
735 canal-crossing highway bridges, the largest in scale
of which is Huanghe-crossing Project. |
| (2)
Huanghe-crossing Project |
The
main trunk canal will cross Huanghe in Gubaizui under
the comprehensive planning of Huanghe Basin. Since its
complex problems and large scale and investment, the
Huanghe-crossing project will be the most critical structure
on the trunk canal. Based on the comprehensive Study
and comparison among the many alternatives, the aqueduct
and the tunnel siphon are technically feasible. Since
the tunnelling method can avoid the contradiction to
the water conditions and the plan of Huanghe, and the
tunnelling method with shield have been a successful
experience in domestic and overseas, it was recommended
that the alternative of tunnelling at Gubaizui would
be adopted in accordance with the canals on both banks.
The tunnels crossing Huanghe will be 7.2 km in total
length. For it, the design water diversion now is 500
m3/s. The project includes two tunnels with
the internal diameter of 8.5 m.
|
| 3.
Investment |
There
are two key factors controlling the construction schedule
of MRP. They are Danjiangkou Reservoir resettlement and
Huanghe-crossing Project on the main trunk canal.
In accordance with the price level by the end of 2000,
the total static investment for MRP equals to about 117
billion yuan. |
| Benefits
of project |
MRP
will mitigate the crisis of water resources in Beijing
Tianjin and North China, and increase irrigated area
by 0.6 million ha, 6.4 billion m3 for municipal
and industrial water supply, 3.0 billion m3
for agriculture, for Beijing, Tianjin, Hebei and Henan,
and significantly improve the biological environment
and investment environment of receiving areas, and boost
the economic development in Middle China.
Heightening Danjiangkou Dam will increase the ability
for flood control of middle and lower Hanjiang and assure
the safety of Wuhan City and the plain in the north
of Hanjiang.
|
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|
 |
The
Danjiangkou Water Conservancy Project |
 |
The
head of canal of the MRP-Taocha sluice |
 |
A
Bkm channel excava:ed downstream of Taocha sluice |
 |
Jianghuai
divide-Fangcheng saddle-back |
 |
Topography
of Mancheng Section |
 |
Trunk
canal-cross sectlon of Yongdinhe River |
 |
Topography
of the diversion mouth of the Tianjin main canal |
|
