From: LIUX1@VAX.LSE.AC.UK
Newsgroups: soc.culture.china
Subject: three gorges dam
Date: 9 Apr 92 12:29:11 GMT

Xuelin Liu
London School of Economics
UK

April 5, 1992



     A Preliminary Report on The Three Gorges Dam Project


The above mentioned Three Gorges dam project is a huge dam project
on the Yangzi River. This important project has not been evaluated
economically, scientifically and environmentally. However, as a
Chinese citizen, based on both my working experience in China and
academic background in Europe (Germany and UK), I would like to
seriously to write this concise report to you; I believe that only
within the international pressure, will China reconsider this
project. After having read some relevant materials, I just
summarise the disadvantages of the project as follows:

1. The Flood Problem

The construction of the dam cannot solve the flooding problem, to
the contrary, it will exacerbate it. It is investigated that the
main flood sources in the Yangzi river are Chuanjiang, Xiangjiang,
Zishui, Ranshui and Lishui. As flood in Chuanjiang alone would not
endanger the downstream parts of the river. For example the 1984
flood in Sichuan province, caused great damage in the province but
not in other provinces. In 1954, the flood in Sichuan was not
serious, since there were heavy storms and rains in Hanjiang,
Xiangjiang, Zishui, Ranshui and Lishui areas, there was
subsequently great flood in the later part of Yangzi river. As with
the severe flood in 1991, the flood came from the rivers mentioned
above and not from Chuanjiang. The Three Gorges dam project will be
built further upstream than all of the rivers mentioned except
Chuanjiang, therefore it will only prevent the flooding from
Sichuan province and will have no function for controlling other
flood sources. In addition, the flood prevention capacity would be
limited to 9.3 billion cubic metres of water compared with the
total flood water, which measured 70 billion cubic metres in 1954.
Therefore, if there is a great flood, the flood must be drained. If
in case there are also floods from Hanjiang or other rivers
downstream, the disaster would be even greater. Actually not only
the original dam should be used, but also the flood preventing
region should also be put into plan.

The Three Gorges dam project will not prevent flooding downstream,
on the contrary, the dam will exacerbate the flooding situation in
the upper reaches of the river. The whole Sichuan Basin only has
Yangzi River to drain the water, the flood drainage is a serious
problem. After setting up the Three Gorges project, there will be
a greater risk of flooding regardless of whether the dam is 150
metres or 180 metres high. It has been reported by Sichuan Academy
of Science that even with a dam 180 metres high, when the mid-dam
water level adjust to 190 metres high, according to the mechanical
principle that the water level in Chungking will be above 210
metres high, and the water level in Jiangjin and Hechuan areas will
be 220 metres high. This indicates that the flood will enter into
the Sichuan Basin. In the areas of Jialingjiang River and Hechuan
to Tongliang, where the landscape is more flatter and densely
populate, a flood would not only raise the water level, but would
also inundate these areas for a longer period. Considering the
people and the intensively located industries there, the loss will
be quite huge. If the tens of billions of investment is just
serving to transfer flooding from downstream to upstream, the
proposed project really should be re-evaluated.

2. Sediment Accumulation---Unsolved Problem

The feasibility report calculated the percentage of soil and sand
of the water based on the previous record. However, because of the
degradation of the land and deforestation in the upstream areas,
the percentage of soil and sand has recently increased. For
example, from 1981 to 1984, the average amount of sand and soil
drained from the river increased from 620 millions tons per year to
680 millions tons. With such a large drainage of soil and sand, it
is a serious problem of sediment accumulation of the dam which will
affect river transportation.

As suggested by the Yangzi River Office, the sediment accumulation
problem can be solved by the methodologies of draining muddled
water and keeping cleaned water and special holes for draining the
sediment. However it is unbelievable to maintain the dam to prevent
flooding, generate electricity and transport. The methodology of
draining muddled water and keeping cleaned water would be
constrained by many conditions and sometimes it will be impossible
to use this method. For example, during the dry season, the water
is cleaner, however, considering the electricity generation and
transportation, the water has to be drained. During the raining
season, the water is more muddy, to prevent flooding, the water has
to be kept. Especially during the flooding period, the water has
more sand and soil, after several floods and consecutive keeping of
water and draining water, the sediment will accumulate layer by
layer, resulting in much sediment being retained in the dam. As for
the drainage of sand, it is viable to drain the sand near the dam,
nevertheless, but impossible to drain the sand accumulated up to
400 to 600 kilometres long.

The investigations reported that the problem sediment accumulation
has been solved. According to the report on "Gezhouba" dam,
sediment accumulation occurs frequently, and the problem would be
much more serious for a larger dam. It is also reported that
because of the sediment accumulation, now only one set of three
generators can work normally, generators have to be stopped in turn
to eliminate sediment accumulation.

3. Transportation

The Three Gorges dam project will seriously affect transportation.
Basically, the dam will restrict the transportation capacity of
Yangzi River. The designed transportation capacity of the dam is
only 50 million tons, but this is only the theoretical figure,
assuming ship loads of only 3000 tons and that ships would pass one
by one; this is far from the reality.

The dam at the same time should generate electricity, keeping water
and draining water, eliminate sediment, the transportation cannot
be 50 millions tons as calculated by the Yangzi River Office. Under
such circumstances, the dam will definitely affect transportation.
For this permanent project, although it can accommodate 3000 tons
of cargo or ship, it will not fit to the economic development for
more heavier load ships to pass. Therefore, the setting up of the
Three Gorges dam will hinder economic development in the southwest
areas of China.

Secondly, for the 150 metres high design, not only will the 10,000
ton ship be unable to Chongqing, Chongqing will also become a dead
port due to sediment accumulation. This will be unfavourable for
the economic development in the southwest part of China and to the
whole country. Therefore, benefits derived from electricity
generation cannot compensate for greater losses.

Thirdly, the only advantage of the Three Gorges dam will be to
widen three hundred kilometres water-way up to the dam. The
distance From Chongqing to the dam is six hundred kilometres;
improved transportation is limited to a certain stretch of the
river only. Compared with the negative effect of the dam, this kind
of benefit is too small.

In addition, the dam itself will also cause transport problems.
Design of transportation part of the dam has been based on the
experience of Danjiankou, where a lift is used for raising the
ships with load of 3000 tons. However, the report from the
transportation department has revealed that the lift in Danjiangkou
is not suitable for passing 3000 ton ships. Therefore it is
unlikely that the lift for 10,000 ton ships is reliable.
Furthermore, a lot of problems exist: (1) if the multiply grade dam
grates can guarantee the favourable communication; (2) the adverse
effect on the shipping between the Three Gorges Dam and Gezouba Dam
because the peak adjustment for generating electricity will cause
turbulence in the river; (3) the river basin right below the dam
will be lowered because of water flows, resulting in too low a
water level in the dam gate area; (4) the main river water-way will
be accumulated with sediment, obstructing transportation. All of
these problems require a series of realistic studies.

4. Electricity Generation

In general the electricity generation will not be cost-effective in
the Three Gorges Dam, since it will require large amount of
investment and a long period of construction, therefore, resulting
in slow speed of production and lower benefit.

If a total of only 20 billion yuan is invested in the project,
there would be some of net benefit; however, the investment will be
several times this amount. It is calculated the total investment
will be more than 60 billion yuan and the unit investment of
kilowatts more than 4600 yuan. Without taking the interest rate
into accounted, the unit investment will still be much higher than
the other dam projects, where unit investment is only 1600 yuan.
The benefit is definitely very low.

There will be no net benefit from the Three Gorges dam until more
than ten years after the dam is into operation because of its
longer time of construction. A real benefit will be seen only 20
years after it starts operation. The project will not only use
large amount of funds, but also delay other projects urgently
needed by the national economy.

Actually a lot of people have put forward many feasible
alternatives, all of these suggesting initial development and
construction of some small and medium size dams on the tributaries
of the Yangzi river. Their characteristics would include a short
period of construction, low investment costs, high speed of
operation and early benefits. Some plans for these alternatives
have already been drawn up, and these suggest that these dams are
economically feasible and easily implemented.

5. Migration---requiring setting up more than ten cities.

Different estimates have been made regarding necessary net
migration flows. For example, for the 150 meters dam alternative,
the migration estimate calculated by the Yangzi River Office is
330,000 people. But the figure calculated by the China City
Planning Bureau  and 11 counties ( there are still three counties
more) within the dam areas is 860,000 people, if with three more
counties, the figure will be more than 1 million people. The former
only calculated immigration fund of 3.5 billion yuan, and by the
latter's calculation, the migration fund will be 11 billion yuan.

Yangzi River region is the most important and prosperous region in
China. The cities along Three Gorges have developed along with the
development of history, some have several hundreds and even more
than a thousand years of history. The 150 meters high alternative
will inundate more than ten cities and the living foundations and
production facilities where more than one million people rely on
them to survive.

Furthermore, when calculating the migration, how can the great loss
be calculated because of the dam, the people have to stop the
present production and to rebuild new ones, how can stop-working be
calculated as percentage of national product?

6. Risks and Diasters

1) Rock Collapse and Landslide


The banks of the designated Three Gorges Reservoir are not the
integrated rocks imaged by the people. The geological structure of
Three Gorges area is very complex. According to the surveys and
investigations made by Sichuan Geology Bureau in recent years, the
places where rock slide and slope collapse can happen are 203
places. There are more than 30 places where the volume of rock
crack and slope collapse will be more than 1000 cubic meters. The
most dangerous one is the rock slip place called 'Lianziyan' where
is 27 kilometres to the dam and the slope collapse place in
'Xintan'.

Lianziyan is located in the south bank of Yangzi river, There are
12 cracks on the top of the rock, of which, the biggest one has
volume of 2.5 to 3 million cubic metres with weight estimated about
more than 7 million tons, where is 310 meters high above the water
level. It is told by the old local people that in the past several
decades, the crack is much widened. If these rock cracks collapse,
the energy of the biggest one is more than 2 billion meter, which
is equivalent to the level of the earthquake. Once this happen, the
degree of destructiveness will be very serious to the dam and it is
hard to estimate the consequences. The problem is not only limited
to rock slide, the rock slide will bring about slope collapse, and
the slope collapse aggravate rock collapse; the chain reaction will
occur in the situation of rock collapse and landslide in Lianziyan
and Xintan.

Xintan landslide site is just opposite to Lianziyan on the north
bank of Yangzi River, which is composed of a 800 metres long, 900
metres high, 70 metres thick of stones. The width of Yangzi River
here is less than 300 metres. If the stones all fall into the
river, the river will be completely obstructed, and the dam will
have no function at all.

The causes of landslide are explained by the geologists that the
geological structure of Three Gorges area is mainly composed of
shales and limestones. The surface of shales has some mud layer,
when water comes into shales, the mud layer will become very
slippery mud and result in slope slide. Therefore, the landslides
often occur after the storms. But for the recent slope slide in
Xintan, before the slope slide happened, there was not storm,
instead, there was a water gushed from the rock, then the slope
slide occurred. It was inferred that the Gezhouba Dam changed the
water permeated structure and accumulated water inside the rock
destroyed the rock structure was the reason for the recent
landslide. Once the Three Gorges Dam Project is completed, the
water level will be more than 100 metres higher than now, it is
worth further studying if the dam will aggravate landslides.

2) Extremely Possible to Cause Earthquake.

It was reported by Wuhan Earthquake Survey department, that in the
world there are more than 80 reservoirs of large and medium size
cause the earthquakes. Of which, some only had very small grade of
earth quake before the completion of the dam, and some even had no
earthquake record before, since the quake can be caused by the
existence of the reservoir.

Near the Three Gorges Dam, there are three earthquake fault regions
and these three fault regions just cross together at the place of
Xintan and Lianziyan. There were 5.1 grade of earthquake happened
recently. The circumstances show that it is easy to have earthquake
in this area. After the completion of the reservoir, the crustal
stress will change, once the earthquake occurs, which not only
involves the safety of the dam, but also can cause a series
reactions such as landslide and rock collapse. Whether the
reservoir will cause earthquake or not basically needs further
study on it. The survey work has not been made either for the dam
area or the reservoir areas, therefore it should be quite risky to
start the project without this kind of investigations.

7. The Negative Effect of the Environment

Because of the dam, a lot of animals in the Yangzi River will be
extinct or reduced. At present there are some very precious animals
like dolphins, sturgeons, Yangzi crocodiles and large variety and
quantity fishes inside the river,  each year some animals need to
go upstream for spawning. Because of the change of the environment,
these animals cannot spawn in the new environment, and will toward
extinct gradually. At present the Gezhouba Dam makes the famous
China sturgeon cannot spawn, although some people use the method to
catch these fishes to pass the dam, however, how can these fishes
be caught one by one? And if there are two dams there should how
many manpower be put to catch these animals during the spawning
period and should these expenses  be included into the total costs?
Since the Three Gorges Dam Project is a permanent project, these
must be put into consideration. There are some examples of fish
reduction and extinction after the dams were built up in the world.

Secondly, with such a big change of landscape, there should be
regional climate shifts. If the setting up the reservoir is good to
the climate or harm to the climate, there is no investigations on
this aspects and the change of the climate will definitely affect
the agricultural production, flood control also the environment in
this areas.


Thirdly, for some historical cities, relics and natural sceneries,
which have priceless values in the human history, once these are
destroyed we cannot restore them at all. The unique scenery of
Three Gorges will also disappear in the earth. These great
calamities to the history of the mankind are, unfortunately, not
put into considerations when calculating the cost of the project.


8. Very Large Amount of Investment

According to the investigations by the relevant people the total
investment in the Three Gorges dam project will be more than 60
billion yuan (equivalent to more than 10 billion US dollars), and
the project will also cause a series of other investments which are
not included in the project budget. For example, the designed power
station will install capacity for generating 13 million kilowatts
of electricity, however, only 3 million kilowatts is the guaranteed
electricity generated by the power station, in order to guarantee
the consumption in industry and agricultural as well as the daily
life consumption, the network of electricity cannot provide enough
electricity for consumption, therefore, a large quantity of coal-
fired power stations would need to be built set up as well.
According to one of the alternatives (the hight of the dam is 150
metres), the dam can prevent flood when the flood is between 150-
170 meters high, if the flood is higher than this, about 300,000
residents who live nearby the dam should temporarily immigrate to
other places. Because of the sinkink and accumulation of sediment
along the dam, frequent  cleaning would be needed to guarantee the
transportation in the river. In addition, it is reported that
another completed dam "Gezhouba" has a very serious sediment
accumulation problem, and only one set of generators work normally;
without solving this type of difficulty, the Three Gorges project
will have even more serious problems.

Conclusion

Summing up all of these disadvantages, it should be clearly that it
is not feasible to have the Three Gorges Dam Project.