October 22, 2017

Damning dams

Book Review: Long-Distance Water Transfer – A Chinese Case Study and International Experiences, edited by Asit K. Biswas, Zuo Dakang, James E. Nickum, Liu Changming. Tycooly International Publishing Ltd, 1983.

Published in The Ecologist Vol. 14 No. 2, March 1984.


This book is the outcome of a study, conducted by Asit Biswas and an international team of experts, of China’s ambitious plan to transfer water from the Chiang Jiang River over some 800 km to plains of Northern China. The study was conducted in conjunction with Academica Sinica and various Chinese water management agencies. It is, undoubtedly, the most serious and comprehensive publication yet to have appeared on the subject of large-scale water development schemes and their social and ecological implications. The main editor is Asit K. Biswas, one of the leading authorities in the field.

The book is made up of an interesting foreword and introduction, both written by Biswas, which are then followed by 28 chapters, each by a different specialist – most of them Chinese but also some Americans – on different aspects of the problem. Some of those specialists are academics, others members of the Chinese state bureaucracy.

Irrigation: the international experience

In Asit Biswas’s foreword, we learn the actual extent of the World Bank’s involvement in large water development schemes. Significantly, the very first loan made by the World Bank to a developing country – Chile, in March 1948 – was for an irrigation and hydropower scheme. From then, until June 1982, the Bank lent US $26.7 billion for agricultural projects, of which $10 billion went specifically to finance no fewer than 285 irrigation projects. The total cost of those projects was probably 2.5 times the amount obtained from the World Bank.

About 38 percent of the money advanced by the Bank for agricultural projects worldwide, has been for irrigation which represents 10 percent of all the money lent by the bank. The rate at which those loans is increasing can be gauged from the fact that 90 percent of all lending for agricultural projects has occurred during the last ten years.

Biswas provides other interesting statistics. According to him, the total amount of irrigated area in the developing world is in the order of 160 million hectares. The future growth rate, however, is likely to fall considerably – both because the most desirable sites will soon be developed and also because the very high cost of irrigating land (which can range from $2,000 to $10,000 per hectare) militates against further development.

There is much talk in official and academic circles of plans to expand irrigated agriculture at the rate of 2.9 percent per annum. Biswas considers that it would be more realistic to suppose that the increase would be of the order of 1.7 percent in the next decades – not fast enough, he says, “to substantially alleviate world hunger”.

He also points out that, in many countries, irrigation schemes have not produced their anticipated benefits and refers to the April 1980 reports by the Club du Sahel entitled The development of Irrigated Agriculture in the Sahel. The report paints

“a very depressing picture: investment costs per hectare are apparently always more than $5,000 and can reach $15,000 and even $20,000. They also require continuous and expensive maintenance. Without maintenance they deteriorate rapidly and their rehabilitation is even more costly than their maintenance.”

What is more, the anticipated high yields and the promise of double annual cropping have not materialised. Although experts insisted that yields would reach 5-6 tons per hectare, the actual yields have varied between 1.7 and 2.6 tons. Moreover, many developed areas are, for various reasons, not being farmed; a lot of land having actually been taken out of production – presumably because of salinisation, though Biswas does not say so. To quote the Club du Sahel:

“Generally speaking, during the past few years, the development of new areas has barely surpassed the surface of older ones which had to be abandoned.”

If this is so, then water development projects in the Sahel are clearly exacerbating food shortages in the region.

Biswas tells us that the experience in Asia may be more encouraging – though perhaps not that much more so. The main problem seems to be water-management. He points out that 50 percent of the world’s irrigated land has, on the admission of FAO, become saline. He also notes that a 1981 study of 30 irrigation projects financed by the World Bank in 15 countries, concluded:

“Overall, water management. . . was found to have received inadequate attention. Insufficient provisions for the system’s operations and maintenance were made at appraisal; insufficient action was taken during implementation. Analysis of water management issues in completion and audit reports as well as in the appraisal reports-tended to be incomplete or superficial; quantitative data was sparse and fragmentary . . . Water supply proved inadequate in 10 cases, unreliable in 6 and inequitable in 3; water losses proved excessive in 5.”

From his personal experience – and this is considerable – Biswas considers that such criticisms are “unfortunately commonplace”. In spite of this, he seems to favour the further expansion of irrigated agriculture. He rationalises that conclusion by trying to persuade himself that the failures alluded to are the result of poor management and that good management is, in fact, possible.

So much for the Foreword. Biswas’s much lengthier introduction doesn’t tell us anything new, though he notes the growing opposition to large water development schemes in developed countries “on environmental and social grounds”:

“Many segments of society are no longer willing to accept such social and environmental costs as the price of progress.”

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Whitewashing the Aswan experience

The first specialist paper is by Mahmoud Abu-Zeid, Chairman of the Water Research Centre, Ministry of Irrigation, Cairo, Egypt. It is largely concerned with the side-effects of the Aswan Dam and is very much the sort of paper one would expect from a government bureaucrat, politically committed, as most of them are, to grossly underplaying the social and ecological effects of these schemes and to overrating their benefits.

Abu-Zeid admits that cultivated land per capita in Egypt has fallen from 0.163 hectares in 1930 to 0.071 hectares in 1978, even though something like 0.42 million hectares have been reclaimed since 1952. He doesn’t mention the equally serious reduction in the quality of the cultivated land – the reclaimed desert, being of very poor quality, while the land which has been lost to salinisation and urbanisation along the banks of the river once ranked amongst the most fertile in the world. Abu-Zeid admits that during the period under consideration, 250,000 hectares of cultivated land have been lost to industrial and urban use and that to maintain present per-capita land availability would entail reclaiming 62,500 hectares of desert every year. On the basis of Egypt’s past record, that target seems unlikely to be achieved.

In the light of those statistics, it is difficult to see how the Egyptian Government can justify the further loss of agricultural land to urban development. Yet it is, even now, considering a project to build 10 satellite cities around Cairo.

Abu-Zeid lists the various features of the Aswan Dam and associated works. He tells us that “the execution of the Aswan High Dam was preceded by very extensive feasibility studies”. This is totally untrue. He also tells us that, at the current rate of siltation, the dam will last 500 years. Again, this is untrue.

He also tries to persuade us that the silt which used to be deposited on Egypt’s agricultural land by the Nile’s annual flood was not really of much use.

“It was found that azote (nitrogen) did not exceed 0.13 percent of the weight of the silt. One-third of this was found to be of value to plant nutrition.”

He then tells us that the loss of that silt can

“be compensated by about 13,000 tons of calcium nitrate fertiliser which is now being produced in Aswan, utilising the power generated from the dam.”

In fact, a more realistic figure is in the area of 100,000 tons of fertiliser, and even this would not compensate for the vast amount of organic material present in the silt which Abu-Zeid presumably does not regard as providing “plant nutrient”. Abu-Zeid also denies that the impounding of the silt behind the Aswan Dam has reduced fisheries in the Mediterranean.

“Shortage of sardines has been reported during the last few years. But this variety has never constituted a major percentage of the total catch in Egypt.”

He tells us that the main catch was from the northern lakes, occupying an area of some 200,000 hectares, and that “these lakes are still fed by agriculture drainage water”. What he does not say, however, is that this drainage water is now highly saline and contaminated with all sorts of agricultural chemicals – chemicals which have caused large-scale fish kills.

He then tells us that the catch in Lake Nasser more than makes up for losses elsewhere. In 1976, that catch was estimated at 20,000 tons. If it was not higher, claims Abu-Zeid, it was because of a shortage of fishing facilities. Once those facilities are improved, he maintains, fish catches of up to 100,000 tons a year will be possible. Such a statement is purely gratuitous.

The health Impact of the Aswan Dam is dealt with in two paragraphs. The project is “believed to increase the potential for aquatic snail vectors of schistosomiasis”, Abu-Zeid assures us, but then this is not a new problem in Egypt. Indeed “parasite’s eggs have been found in mummified viscera from Tutenkhamun’s tomb”.

In any case, he goes on to claim, the problem can be solved by spending $34 per hectare a year on molluscicides, by covering field drainage systems and by including “health control components” in new projects. What those “health control components” consist of and how they are to work, Abu-Zeid does not say. The problem of salinisation is also grossly underplayed. Indeed, according to Abu-Zeid, it can be solved simply be appropriate management.

All in all, this article is a callous and cynical piece of political propaganda of the sort one must, unfortunately, expect from politicians and bureaucrats throughout the world who are desperate to justify the destructive enterprises they promote to maintain themselves in power.

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Pakistan and Japan

A paper by Gaylord V. Skogerboe, of Colorado State University, deals mainly with more recent water development schemes in Pakistan, in particular with methods of overcoming the serious salinisation problem in that country. He rightly concludes that the future lies in small-scale schemes at a village level and laments the shortage of material on the traditional organisation of such schemes in Pakistan. He provides a useful bibliography on the literature that does exist on this subject.

A paper by M. Okamoto, of the Faculty of Agriculture, Iwata University, Japan, deals briefly, but realistically, with the Japanese experience. He points to the problems “of obtaining the consent of the people who have to be resettled in other places due to inundation, some of whom even have to change their profession since their farms will be submerged”.

He also notes that even after receiving compensation, such people “cannot maintain their living standard at the same level as before the inundation”. Hence they lobby against these schemes. He goes on to point out that

“a comprehensive and political judgement on these problems may be better than the monetary assessments that are currently conducted. It is difficult to assign monetary values to environmental impacts.”

Not surprisingly, people have now

“begun to doubt the necessity for these large scale Interregional Water Transfer projects. . . Residents to be affected by the construction of reservoirs oppose the plan and so do people who fear further environmental disruption.”

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The Texas Water System

In another paper, Charles Greer from Indiana University, describes the Texas Water System and its possible environmental impact. He points out that the present withdrawal of water for irrigation on the High Plains of Texas “is vastly greater than annual recharge”. Indeed, he argues that without new sources of water from outside the area,

“the maintenance of production in this agricultural region will not be possible a few decades in the future.”

Nor, for that matter, would it be possible to maintain urban and industrial growth in such centres as Dallas – Fort Worth, Houston or San Antonio. In fact, the expected increase in the population of Texas from 11 million in 1970 to an estimated 30 million by 2020 – with a corresponding increase in industrial production and other economic activities – makes new supplies of water essential.

Nevertheless, the Texas water plan was rejected in 1969 by referendum and a study in 1973 showed that the conveyance of 10 billion cubic metres of water from the Mississippi River to the High Plains, though practicable from an engineering point of view, was not economic. However, a further study in 1977 predicted that, over a large area of the high plains, the underlying aquifer would be depleted by the year 2000 and that the increased price of agricultural produce might make the plan more economic.

Greer notes that few of the environmental implications of the Texas Water System have been studied. In the original study, the increased salinity of the river for export to West Texas was looked at, as was the quality of water imported from the Mississippi, though not in a detailed way. Mention was also made of the

“recreational and scientific significance of impacts on freshwater fish, waterfowl and other wildlife habitats, which would be affected by reservoir development in the exporting basins of East Texas.”

Beyond this, however,

“none of the major changes in hydrobiology of these basins, which could result from the proposed development, were reported as having been studied.”

In the 1977 revised draft, environmental considerations still remain surprisingly small and “very much secondary to the plan’s main consideration of engineering and economic feasibility”. Indeed, says Greer, the environmental problems are perceived largely as “political obstacles to the plan’s adoption” rather than as “geographic realities in which development is to be carried out”.

Interestingly enough, Greer points to the similarity between the Texas water scheme and the proposed Chang Jiang scheme in China. Both projects involve a similar scale of transfer – 10 billion m3 conveyed annually over distances of 600 to 1,200 km in the Texas case, and about 15 billion m3 conveyed some 800 km in the Chinese proposal.

General environmental parameters are similar in both cases. Water is exported from a humid basin of the largest river of each continent to a region of semi-arid plains, to be used mainly for irrigation but also for municipal and industrial purposes. However, because of population density and the intensity of agricultural land used in China, the Chinese scheme is likely to have a far greater social, ecological, political and economic impact than the Texas Scheme. Greer pleads for planners to ensure that environmental systems are studied in the same detail as the economic and engineering ones. If not, he warns,

“the lessons that have been learned in the US and elsewhere over the last decade will be needlessly repeated.”

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The Chang Jiang Project

Perhaps the most comprehensive paper on the Chang Jiang diversion project is that by Bruce Stone, of the International Food Policy Research Institute, Washington DC. First of all, he describes the scheme itself in considerable detail.

Apparently the idea of diverting water from the Chang Jiang area to drought-stricken North China Plain and to even drier areas of the Northwest, is an old one. The area south of the Chang Jiang contains one third of the total cultivated area in China and receives three-quarters of the total flow of surface water. North China, on the other hand, with half the nation’s cultivated land, receives only 8 percent. Rainfall varies in China’s agricultural areas from over 2,000mm in the Southeast to 200mm in the Northwest. Moreover in the North, rainfall is not only low but uneven and unpredictable.

Three possible (not mutually exclusive) routes have been proposed for the diversion; a western route, a middle route and an eastern route. The western one has never been surveyed very intensively, the eastern route was surveyed in detail in 1978 and the middle route in 1979. Each is likely to create different environmental problems.

At the moment the middle route appears to be most favoured. It would require the construction of a 1,265 kilometre canal to Beijing which would cross the Huang He west of Zhengzhou and pass through the Nanyang Basin in southern Henan. The scheme would irrigate 5 million hectares and would bring an average 10 km3 of water a year to the Hai He basin. According to Stone, there would be

“a substantial risk of salinisation with the Middle Route, although probably less severe than in the case of the East Route”.

The problem of resettlement will be a serious one. When the Danjiangkou Dam was constructed in the 1960s, several hundred thousand people had to be resettled. The height of the dam would have to be raised if the middle route were adopted, which would mean displacing a further 200,000 or so people.

Apart from the social and ecological problems associated with the scheme, its cost is likely to be extremely high. Indeed, Stone asks:

“In view of the immense initial costs and the substantial environmental risks and related costs and expenditures required, why is the project being reconsidered at this time?”

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Inappropriate crops

He then discusses the North’s assumed need for the southern water and the possible alternatives to the proposed scheme. He argues that the Chinese diet plays a critical role in determining water requirements. At present, 90 percent of per capita caloric intake is supplied by food grains. Stone points to the gradual displacement, over the last few decades, of coarse grains by high-yielding and high-valued strains of wheat and maize. To maintain that trend, more irrigation water is required. But is the trend desirable on social and ecological grounds?

Stone argues that much of North China, especially Shandong, is characterised by low-lying depressions. To grow wheat, corn or cotton under irrigation in such depressions is to favour salinisation. He suggests that sorghum and soybeans might be grown instead. In addition to being better suited to the terrain, both crops have other advantages. Neither crop requires much irrigation water, moreover

“They are valuable as hog feed; soybeans have a high nutritive content, improve soil fertility and are a source of oil, and sorghum stalks provide fuel and nutrients.”

He points out too that attempts to increase grain production in unsuitable areas has generally been unfortunate. Though high yield increases have been obtained, salinisation has turned out to be a very serious problem.

“Two-thirds of the 4 million hectares of irrigated land in north China were threatened with salinisation in the early 1960s.”

Remedial action was taken and a large number of tube wells were dug in order to bring about a fall in the water table. The results were satisfactory and the area of saline farmland was considerably reduced. In spite of this, however, the cultivated area fell in the Hae He basin by about a million hectares between the 1950s and the 1970s. The same is true in Henan where the cultivated area fell by 1-2 million hectares.

Stone does not make it quite clear why this should have been so if the battle against salinisation was as successful as he made it out to be. Indeed, he himself points out that salinisation

“was not only the principal man-made cause of the largest grain production setback in the People’s Republic history during the Great Leap, but has been on the rise again in north China since the mid 1970s.”

Although the large scale building of tube wells has resulted in the beneficial lowering of the water table in some areas, in others it has caused such a serious fall in the water table that irrigation agriculture is now itself under threat. Little data has appeared outside China on this problem, which is surprisingly similar in the American Southwest, though Stone does not mention this. Indeed, if the problem is as serious as in the US Southwest, then this goes a long way towards explaining the importance of the proposed water-diversion schemes.

The fact that a large number of constructed wells – most notably in the provinces of Shandong, Hebei and Henan – are not actually operating, suggests that it may be. This may be due to a lack of equipment and other ancillary facilities for bringing water into the fields but it may also be due to increasing groundwater depletion.

In conclusion, Stone considers that the Chang Jiang diversion is not required to bridge the gap “between supply and demand for food in China during the current decade”. These schemes would undoubtedly benefit agriculture in the north but only “if the very serious risk of widespread salinisation can be eliminated” – which we know, on the basis of the total world experience, is extremely unlikely, although (again) Stone does not say this. He ends by concluding:

“The mentioned costs of the projects are very large and may well be under-estimated. The implied environmental damage and associated economic loss is very substantial at current levels of technical and administrative preparedness (particularly in the area of local water management).”

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Loss of soil fertility

In their contribution to the book, Guo Huancheng and Xu Zhikang of the Institute of Geography, Academia Sinica, warn that salinisation and alkalisation are already serious problems in the area which will be affected by the proposed water transfer scheme. There are some 2.7 million hectares of saline soil in the region, which accounts for about a fifth of the cultivated area in the plains. They argue that there is too much monoculture in the region, and that the area devoted to multi-cropping is too large – with the result that

“Soil fertility is constantly dropping due to the lack of proper soil utilisation or nutrient maintenance”.

They also point out that

“a long-term one-sided emphasis on high yielding grains and on increasing the multiple cropping index has led to a great expansion in the area devoted to maize, wheat and sweet potatoes at the cost of crops such as soybeans, sorghum and millet which are resistant to flooding and replenish the soil.”

Once again, the result has been a fall in soil fertility. Indeed, they tell us,

“The barrenness of the soil has become an important factor limiting the region’s agricultural yields and their stability.”

The authors clearly have grave reservations about the scheme, although they do not say so explicitly. They recommend very thorough research into all the various environmental aspects of the scheme, including its possible effect on soil salinisation, and suggest that proper drainage be installed and that every other necessary measure be undertaken to reduce salinisation.

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The official view

A paper by Yao Bangyi and Chen Qinglian, from the Ministry of Water Conservancy, is also worth noting. As might be expected in a paper by two state officials, the emphasis is on the great benefits to be derived from the proposed water transfer scheme. Thus the project is expected to provide an additional 3.8 million hectares of irrigated farmland and a guaranteed water supply for a further 1.3 million hectares.

The scheme is also expected to supply 2.8 km3 of supplementary water for industrial, municipal, domestic and navigational use. At the same time, large pumping stations will be able to drain up to 5,000 m3 per second of excess surface water away from an area of 1.8 million hectares, which will reduce waterlogging and salinisation. A vast increase in fish production is also promised. Only in the last few lines are environmental impacts mentioned, and then it is only to suggest that “we should know what they are likely to be”.

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Supporting deficiency with deficiency?

In their paper, Xu Yuexian and Hong Jialian, of the Institute of Geography, Academia Sinica, deal specifically with the likely environmental impact of the proposed South-to-North water transfer project on the Chang Jiang River basin. At present, some 25 million hectares of the basin are cultivated, producing 40 percent of the total national grain output and 35 percent of the country’s cotton.

The area – which, in 1978, had a population of 342 million – is also heavily industrialised, “embracing over 40 large and medium-sized cities and industrial or mining bases”. Indeed, according to the authors, “the total value of the basin’s industrial output amounts to approximately 40 percent of the national total”. The middle and lower reaches of the basin – which will be most directly affected by the water transfer scheme – are not only the chief grain and cotton growing areas within the basin but also the most industrialised.

It is from the Chang Jiang river that much of the water, to be used to irrigate the dry northern plains, is to be derived. Xu Yuexian and Hong Jialian point out that, over the last 30 years, more than 40,000 reservoirs of all sizes have been built in the Chang Jiang basin, with a total capacity of 100 km3. The irrigated area has expanded to 6.7 million hectares. The demand for water for industrial and domestic purposes is constantly increasing and the availability is beginning to decline. The problem is so general that the authors conclude:

“Transferring water from the Chang Jiang northwards is nothing more than ‘supporting deficiency with deficiency’, if we consider future increases in water use and the fact that the Chang Jiang basin is not all that rich in water resources.”

Nevertheless, Xu and Hong consider that the project is feasible and that it will not prove too damaging to the area. The chief problem, as they see it, is the salinisation which the scheme is likely to cause in irrigated areas.

“Over the past 30 years, the area of saline soil in the proposed water transfer region has fluctuated constantly. In the three provinces of Hebei, Henan and Shandong, there was a total of 1.9 million hectares of saline soil in the mid 1950s. This area expanded to 2.3 million hectares in the early 1960s due to the diversion of the Huang He for irrigation and to water storage on the plain. The saline area dropped to 1.4 million, by the mid 1970s, however, because of improvements in the standard of drainage with the harnessing of the Hai He and other river basins and the lowering of the water table due to the development of pump well irrigation; but the tendency to expand seems to have returned in the late 1970s. At the end of the 1970s, the area was about 1.9 million ha. This corresponds to the rise in the water table along both sides of certain rivers associated with the construction of water-impounding dams. At present there is a total of 2.7 million ha of saline soil, amounting to about 15 percent of the total arable land from the Shaying He system of the Huai He basin in the south to Beijing and Tianjin in the north. Moreover, there is an additional 4.7 million ha of potential saline soil which is most vulnerable to secondary salinisation if affected by detrimental factors.”

Xu and Hong appear to take it for granted that the project will be built – whatever the likely dangers – and end up suggesting that all the usual safeguards should be taken in order to reduce the damage to a minimum.

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The problems of management

Another interesting paper is by James E. Nickum, from the Department of Asian Studies and Agricultural Economics, Cornell University. Like Xu and Hong, he sees the “spread of secondary salinisation” as one of the “likely deleterious impacts” of the proposed scheme. The threat, he argues, is particularly worrying because of the inadequacy of irrigation management in China – a problem which is, apparently, much alluded to in the national press.

“There has been a long-standing criticism in the literature of ’emphasising construction to the neglect of management’ and ‘only grasping construction without regard for effectiveness’. A Renmin Ribao (People’s Daily) editorial on 13 December 1963 estimated that as much as 6.7 million hectares could be added to the area irrigated and drained by existing projects. More recently, agronomists in Henan claimed that the necessary ancillary projects had not been added to 10 large reservoirs built in the 1950s or to the more recently installed 110,000 tube wells, leaving the province’s irrigated acreage 2.7 million hectares below its potential.”

From colleagues attending the East China Water Transfer Symposium, Nickum reports, he learnt that poor management had led to the following problems, among others:

  1. Farmers in the upper reaches use too much water while those in the lower reaches do not receive enough.
  2. Though good results are achieved in experimental areas, they are nothing like as good elsewhere – largely because the peasants are reluctant to adopt the innovations proposed by government agricultural experts. Drainage, for instance, is regarded as being too expensive.
  3. Poor management has led to secondary salinisation in some parts of the North China Plain. This is attributed, in particular to seepage from canals: “Among the sites we visited, seepage rates are 40 percent in the long-established People’s Victory Canal system . . . and over 50 percent in the channels of the Shijin Canal system.”

Nickum goes on to point out:

“The area watered by each cubic metre is too vast, up to 2,000 hectares. This means that water is in the main canals for up to 300 days a year, keeping the nearby water table high. Some places irrigate too heavily and too often.. . (and) irrigation is emphasised to the neglect of drainage. Sometimes canals even cut off the natural drainage routes.”

Nickum points out that these problems are similar elsewhere, quoting Chambers who talks of “managing those who manage the water”

.

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Salt water intrusion

The question of possible salt-water intrusion in the Chang Jiang is dealt with in a paper by Shen Huanting, Mao Zhichang and Gu Guochuan of the Estuarial and Coastal Institute, East China Normal University, and Xu Pengling of the Shanghai Water Works Corporation. They point out that salt-water intrusion is already a serious problem in the Chang Jiang estuary, particularly during the dry period from December to April. It already

“directly affects and threatens the water used for industry, agriculture and daily life in Shanghai and some coastal areas of Jiangsu Province.”

This is largely because of the continual deepening of the channel to the ocean in the Chang Jiang estuary in order to improve water transportation. Shen and his colleagues conclude:

“If water is transferred at the rate of 1,000m3/sec along the East Route, saltwater intrusion will definitely be worsened in the Chang Jiang estuary. This will also alter the ecological environment of fishery resources. Therefore, serious attention must be paid to these effects in the planning of the south-to-north transfer.”

Whether the other proposed routes would have less deleterious effects is not discussed in detail. It appears however, that they provide both advantages and disadvantages with regards salt water intrusion.

Another article, which deals specifically with the likely ecological effects of the diversion, is that by Zhu Shouquan, Wang Zunqin and Hseung Yi of the Institute of Soil Sciences, Academia Sinica. They describe how the high silt content of the Huang and Hai rivers, which flow through the Huang-Huai-Hai Plains, has led to the elevation of the river beds above the surrounding land surface, thereby intensifying lateral seepage and causing the water table to rise.

Evaporation rates are very intense, especially in the spring when the area often suffers from drought. The summers are extremely hot and rainy – and summer flooding and salinisation is common. There is often not enough moisture in the spring for sowing; moreover, because of the soil’s high salt content, it is very difficult to cultivate cereals successfully without irrigation. Water is a critical factor. When there is too little of it there is drought, while too much in this area leads to water-logging. The high salinity of the soil, leading to the accumulation of salts on the surface of the land, is the other critical factor.

In the late 1950s a large number of reservoirs were built blocking natural drainage channels. There was considerable seepage and the water-table was raised, with the result that extensive salinisation occurred. The critical question is whether the south-to-north water transfer “will aggravate the secondary salinisation of the soil which is a threat north of the Huang He and in coastal areas.”

Whichever route is adopted, increasing the water input of the Huang-Huai-Hai Plain must fundamentally alter the present water-salt balance. The authors stress the importance of taking the appropriate measures to reduce the damage.

“In an engineering system . . . diversion, storage, irrigation, drainage and management of water should be regarded as a single entity, beginning with the design and installation of a drainage system prior to irrigation.”

Unfortunately, they go on to note,

“this is rarely done in practice and therefore the soil-plant ecology has not been improved.”

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Conclusion

In general, almost all of the academic contributors to this book accentuate the terrible social and ecological disruption which is likely to be caused by China’s proposed water transfer scheme. The bureaucrats who presented papers, on the other hand, grossly exaggerate the benefits to be derived from the project and hardly mention the social and environmental consequences.

Equally significant, none of the academics (with the possible exception of Stone) actually goes so far as to suggest that the Chiang Jiang scheme should not be built. Is this because they know, from past experience, that politicians and bureaucrats are unlikely to be moved by the dangers they highlight? Because they assume that the construction of the scheme is a foregone conclusion – and that all they can do is to try and persuade the authorities to undertake those measures which will reduce its adverse effects to a minimum?

Sadly, that conclusion is hard to resist. If the experience of similar projects in the Soviet Union, the USA and India is anything to go by, the warnings and advice of concerned academics will have little bearing on the decision to build the Chiang Jiang scheme. Indeed, that decision will almost certainly rest on purely political and economic considerations.

One can only fear for the future of the tens of millions of people now living in those areas of China earmarked for development.

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