Introduction

The water resources of Central Asia have suffered from a long history of mismanagement. Prior to 1960, the Aral Sea (Fig. 1) was one of the four largest lakes in the world with an area close to 70,000 km2. By 2007, the sea had declined to just 10 % of its former self and had split into four smaller lakes and, by 2014, the largest of these became completely desertified. Although much of the early damage was done when Central Asia was under control of the Soviet Union, the situation deteriorated in the early 1990s when the Soviet Union collapsed and the task of managing the region’s fragile “transboundary” water resources became the shared responsibility of Uzbekistan, Tajikistan, Turkmenistan, Kyrgyzstan and Kazakhstan (Smith 1995). The rivalry and deep mistrust that exists between these guardian nations has seriously impeded the close cooperation required for constructive, water management, and decision-making. While the water problems and environmental issues of Central Asia are clearly very serious, most observers believe they probably have more to do with water management policies and practice than they do with a lack of available water.

Fig. 1
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(modified after Howard and Griffith 2008)

The countries of Central Asia showing the Aral Sea Basin

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In September 2013, Chinese President, Xi Jinping travelled to Astana, Kazakhstan, where he reaffirmed China’s commitment to promoting world economic growth and international collaboration by calling for the creation of a new “Silk Road Economic Belt” (http://news.xinhuanet.com/english/china/) that would link Southeast Asia to markets throughout Russia, Europe, the Middle East and beyond. Such a project would bring profound economic benefits to the entire region and create wealth and prosperity in some of the world’s most impoverished areas. Central Asia would be the gateway to this project and pivotal to its success.

The Chinese President’s ambitious goal is clearly attainable. However, questions have been raised (Li et al. 2015) whether the project can be completed without causing severe environmental degradation including irreversible damage to Asia’s water resources. In China, a key part of the proposed route passes through arid and semi-arid regions where water resources are already under severe stress (Libert et al. 2008). Such concerns do not stop at the Chinese border. The “New Silk Road”, as it is referred to by many Chinese citizens, threatens to compound the serious water resource issues of Central Asia, a region where the inherent complexity of the natural system, a paucity of scientific data and sound research, and cross-border tensions, seriously inhibit the development of solutions that may mitigate environmental impacts.

This paper provides an overview of the water resource issues in Central Asia and explores the challenges that lie ahead. It examines the transboundary nature of the hydrological system and evaluates its current status given many decades of maladministration and abuse. It considers the potential impacts of climate change and the long-term sustainability of the water resource (Baba and Gunduz 2011; Baba et al. 2011). Moreover, it considers the potential impacts that may result from the development of the “Silk Road Economic Belt” and the proactive measures that need to be put in place to minimise environmental degradation. A fundamental concern is that the development may place too great a burden on a water management system in Central Asia that is already seriously dysfunctional (McKinney 2004) and in urgent need of reform.

The water resources of Central Asia

Occupying an area of over four million km2, the post-Soviet states of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan that comprise “Central Asia” (Table 1) cover a land mass that exceeds Pakistan, India and Bangladesh combined. Geologically, this region lies within the Central Asian Orogenic belt (CAOB), a complex region (Kröner 2015) that extends eastwards from the Ural Mountains to the Pacific region. It represents one of the largest orogens on Earth and records 800 million years of tectono-magmatic activity dating back to the Mesoproterozoic. In terms of the study area, it includes the Tian Shan and Pamir mountain ranges which formed during the Cenozoic times when a collision between the Indian and Eurasian continental plates created the Himalayas. These mountains represent the major source of water supply in the region, as well as a crucial source of hydroelectricity.

Table 1 Countries of Central Asia (population and GDP data from 2012)
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The topography of Central Asia is shown in Fig. 2. The lowland area to the north and west is dominated by the Turanian Plain which includes the KyzylKum and KaraKum deserts (Bjorklund 1998). The Tian Shan and Pamir mountains rise to 7500 m above sea level in the south-east of the region and essentially prevent moisture-rich winds from the Indian Ocean to the south from reaching Central Asia’s landlocked interior. As a consequence, precipitation over much of Central Asia is low and irregular, especially towards the north-west where high solar radiation gives rise to relatively low humidity and arid conditions.

Fig. 2
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(http://www.britannica.com/place/Central-Asia)

Topography of Central Asia

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Figure 3 shows a generalised cross section across Central Asia from the mountains in the south-east to the dry interior in the north-west. The primary source of fresh water for Central Asia’s rivers and aquifers lies in the mountains where precipitation, locally above 2000 mm/a, significantly exceeds evapotranspiration. In many cases, the primary source of aquifer recharge is glacial meltwater during the warmer months. Towards the drier north-west, effective precipitation (precipitation − evaporation) declines significantly and both run-off and net aquifer recharge are close to zero for much of the year.

The most important aquifers occur in the mountains and foothills where deep valleys have accumulated many hundreds of metres of coarse alluvial sediment. For example, Kyrgyzstan’s capital, Bishkek (pop. 871,000 in 2012) (Fig. 2) relies exclusively on the abundant supply of groundwater from underlying Quaternary sediments for all its domestic and industrial needs (Morris et al. 2002, 2005). As indicated in Fig. 4, Bishkek’s aquifers are locally up to 350 m thick and have a transmissivity of 6000 m2/day and can readily supply around 5 m3/s of good quality water. They are, however, highly vulnerable to pollution and are seriously threatened by a wide range of industrial activities (Ó Dochartaigh 2000). Pozdniakov and Shestakov (1998) describe a similar alluvial valley aquifer associated with the Kafernigan River, a tributary of the Amudarya, where the Quaternary sediments, 200–300 m thick, exhibit a transmissivity of 2000 m2/day.

Fig. 3
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(modified after McCray 1998)

A generalised southeast to northwest cross section across Central Asia

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Fig. 4
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(from Morris et al. 2002, 2005)

Cross section of the aquifer underlying the Kyrgyzstan capital of Bishkek

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Regionally, the general direction of groundwater flow is towards the Aral Sea in the north-west. Few groundwater studies have been undertaken in this area as it has been sufficiently serviced in the past by surface water from the Amudarya and the Syrdarya, two of Central Asia’s most important rivers (Fig. 1). The most extensive aquifer in the lowland region is probably the Shatlyk aquifer, a thick Lower Cretaceous sandstone aquifer (see Fig. 3), that extends in a north-westerly direction from the base of the mountain ranges (McCray 1998; Ulmishek 2004). In many areas, this permeable unit is better known for its natural gas reserves than its water supply potential but it can provide adequate supplies of good quality water in the foothills, close to its recharge source. Gascoin and Renard (2005) suggest that the inflow of groundwater to the Aral Sea due to regional flow amounts to 4 km3/year, and that without this contribution, the Aral Sea would have declined much more rapidly. Jarsjö and Destouni (2004) estimate that groundwater would have accounted for just 12 % of the water entering the Aral Sea in 1960 but became the only significant source of inflow by the early 2000s.

In general, and despite some very comprehensive local studies, there remains a serious lack of hydrogeological data at the regional scale. Given the complex interfingering of national borders in Central Asia, especially in the mountains, it should be no surprise that many of the aquifers are transboundary in nature and, therefore, a shared resource with shared responsibilities for management and protection (Puri 2001; Puri and Aureli 2005; Eckstein and Eckstein 2005). Central Asia Water (CAWATER) has estimated that 30 % of the 339 aquifers identified in the region can be considered transboundary; however, given that many of the aquifers are undoubtedly interconnected in a regional sense, the true percentage is likely to be considerably higher.

CAWATER also publishes data on Central Asia’s groundwater reserves and how it is used (Table 2). The groundwater reserves shown represent the amounts that can be withdrawn without significantly affecting surface water flows. While the data imply that groundwater is being underutilised with only 76 % of the available renewable supply being abstracted, it is not made obvious why this is so. CAWATER does indicate that the salinity of the groundwater naturally varies up to 3000 mg/l and that groundwater pollution due to return flows (wastewater) is a significant problem; thus, unsuitable water quality is probably the greatest constraint on groundwater use.

Table 2 Groundwater reserves and use in the countries within the Aral Sea basin (km3 per year) (Central Asia Water (CAWATER)—data extracted from website January 14, 2016)
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It should be noted that while the available groundwater reserves (13.1 km3 per year) are significantly lower than the annual river flows of the Syrdarya (38 km3) and Amudarya (77 km3), these rivers rely substantially on groundwater, in turn fed by glacial meltwater, to maintain their flows. Thus, although groundwater abstraction via wells accounts for just a few per cent of the water used for irrigation, it does play a crucial role by feeding the rivers from which the irrigation water is drawn. Approximately 100 km3 of water is used every year in Asia to irrigate over 8 million ha of land.

Significantly, no estimates are provided on the total reserves of groundwater held in storage, volumes that are likely be to be several orders of magnitude greater than the “renewable” reserves available on an annual basis. Neither are data provided on transboundary flows. Such types of information are essential for the development of strategies for the sound management of Central Asia’s water resources.

A history of resource water mismanagement in Central Asia

It is inevitable that concerns for the potential environmental impacts of the Silk Road Economic Belt project are driven, at least in part, by knowledge of the devastation caused by the last major effort to stimulate economic prosperity in Central Asia. This refers, of course, to the desiccation of the Aral Sea (Fig. 5).

Fig. 5
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(modified after Hecht 2014)

Aral Sea shown in 1960 and in early 2014. Its area has reduced by over 90 %

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The problem dates back to the 1960s when Central Asia was part of the Soviet Union. A conscious decision was made at that time to harness the Amudarya and Syrdarya in the mountains to generate hydroelectric energy and to divert these same rivers in their lowland reaches to irrigate a vast expanse of semi-arid plain, predominantly for the production of cotton. These actions inevitably reduced the flow of water to the Aral Sea which dried up rapidly in succeeding years.

The project was plagued with problems from the start. The extensive network of irrigation canals proved to be hydraulically inefficient and failed to deliver the volumes of water required to maximise crop production (McCray 1998). It has been suggested that less than half the water diverted from the rivers managed to reach the crops. As an inevitable consequence of the irrigation losses, shallow groundwater tables rose and, in turn, led to soil salinization and a loss of soil fertility. This whole episode proved tragic for a region so dependent upon agriculture for employment (UNDP et al. 2005).

The situation became dire in December, 1991 when the Soviet Union dissolved and the resource-sharing system that had been imposed on the region by Moscow, disintegrated. Five, now independent sovereign nations, Kazakhstan, Kyrgyzstan, Uzbekistan, Tajikistan and Turkmenistan inherited overnight an old, inefficient and unsustainable system of water utilisation that desperately required reform (Djalalov 2003; McKinney 2004). In effect, the Aral Sea Basin had become a shared “transboundary” water resource, and the development of sustainable and equitable water management practices had become one of many shared responsibilities.

Under Soviet control, Central Asia had been split into five Soviet republics with all administrative matters in these republics determined by Moscow, i.e., there had been a single, top-down system of governance that was responsible for all water-related decision-making. Following independence, the countries of Central Asia began collaborative efforts designed to manage, and protect their transboundary resources (Djalalov 2003). They formed the Interstate Water Coordinating Committee (ICWC) in 1992 and the International Fund to Save the Aral Sea in 1993 with the support of international organisations (UNEP 1992; Bayarsaihan 2003; McKinney 2004). Unfortunately, political rivalries, economic competition and nationalism have seriously undermined efforts to solve Central Asia’s water-related problems. At the political level, there appears to have been insufficient interest on a wide enough scale to improve water management and even within individual countries there has been a serious lack of coordination on water issues, with three different government bodies independently regulating the three different sources of water (surface water, irrigation water and groundwater).

Twenty-five years after the break-up of the Soviet Union there is little evidence to suggest there has been any abatement of tensions in the region, and the joint management and protection of Central Asia’s transboundary water resources remain an elusive goal. Concerns are no better illustrated than by recent events in the Fergana Valley (Fig. 6), the agricultural heartland of Central Asia and home to one in four of the entire population of Central Asia. It is also one of the region’s most volatile areas with frequent violent clashes involving water. Key drivers to this unrest are wide ethnic diversity, interspersed populations, complex borders, diminishing resources, deteriorating infrastructure and religious extremism (Stratfor Global Intelligence 2013).

Fig. 6
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(modified after Stratfor Global Intelligence 2013)

Fergana Valley

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The Fergana Valley (area ~22,000 km2) lies between the Tian Shan Mountains to the north and the Gissar-Alai range to the south. It hosts the upper reaches of the Syrdarya River and is a major source of food for Central Asia. The rapidly growing population of the Fergana Valley (population growth of 32 % in the last 10 years) consists mainly of Uzbeks, Kyrgyz and Tajiks. Correspondingly, the valley is divided between Uzbekistan, Kyrgyzstan and Tajikistan, although many of the borders, artificially created during the Soviet Union era, are seriously contested. Uzbekistan, Kyrgyzstan and Tajikistan share 3681 km of borders of which 961 km are challenged. Many of the disputed sectors are in the Fergana Valley (The International Crisis Group (ICG) 2014).

Dukhovny and Horst (2008) reported some success with the introduction of IWRM (Integrated Water Resource Management) in the basin. However, progress is slow, and it is clear that the lack of a shared vision on water security will continue to increase the risk of competition over water, ultimately leading to further degradation of the natural resource. ICG (2014) describes the situation in the Fergana Valley as “acute, complicated and urgent” and raises the spectre that competing demands for water could eventually lead to armed conflict in the region.

The compounding effects of climate change

Climate change will inevitably compound water problems in the Fergana Valley, although scientists have yet to agree on the magnitude of the effects. Novikov (2005) reports that average regional surface temperatures in the Fergana Valley increased between 1965 and 1995 by a very significant 0.5 °C, and a climate, land-ice and rainfall–run-off model developed for the Syrdarya by Bernauer and Siegfried (2012) demonstrates that climate change will seriously affect the river’s run-off regime. The modelling did not support the frequently heard concern about aridization of Central Asia over the near term (Malone 2010; Swarup 2009). However, it did indicate climate change will impact the Central Asia region mainly through temperature effects on the snow and ice cover in the Tian Shan mountains and that the distribution of water in the course of a year could change dramatically. The modelling was carried out for a period of 50 years using an integrated systems model approach that couples climate and land surface hydrology including snow and ice storage (Pereira-Cardenal et al. 2011; Siegfried et al. 2011). As determined by Bernauer and Siegfried (2012):

  • The most important impact of climate change in the Syrdarya basin will be significant changes in the seasonality of run-off. Due to warming, the run-off peak associated with glacial ice melting will shift from the current spring/early summer regime towards a late winter/early spring regime. This change has important repercussions for reservoir management since it will mean a significant reduction in water availability during the crop growing season when over 90 % of total average annual consumptive water use for irrigation purposes occurs.

  • Depending on the climate change scenario, glacier melt can be expected to continue to contribute to river flow during the entire first half of the twenty-first century. Under the worst anticipated case condition for the region (2.9 °C warming until 2050), only one-third of the present land-ice volume (approximately 200 km3) is likely to melt over this period.

  • Glacier lengths will decline significantly across all size categories as land ice continues to melt. Retreating glaciers will leave behind unstable terminal moraines that will trap large volumes of meltwater. Subsequent collapse of these moraines could cause catastrophic downstream flooding (Nayar 2009) and serious loss of life. The Fergana Valley region has previously suffered glacial lake outbursts and mudslides and is likely to be especially vulnerable.

Potential environmental impacts of the new “Silk Road Economic Belt”

The original “Old Silk Road” (Fig. 7) was established during the Han Dynasty over 2100 years ago to stimulate trade between China and Europe. In those days, it would take many months, perhaps years, for caravans of heavily laden camels and horses to reach Europe from China along various routes that inevitably encountered both mountains and sun-baked deserts. Today, trains carrying containers with electronic goods, construction materials and other cargo travel from Chongqing in Southwest China to Duisburg in Germany’s industrial Ruhr region, a distance of nearly 11,000 km in 2–3 weeks. However, this is just the beginning. Chinese President, Xi Jinping’s visionary “Silk Road Economic Belt” is anticipated to revolutionise the flow of raw materials and goods across Asia, creating jobs and wealth along the entire route. Details remain scarce but Central Asia will be an important hub for this project with Beijing and Astana (Kazakhstan) already establishing an agreement which would create free trade zones along a proposed railway network between east and west. Highways, pipelines and rapidly growing cities will not be far behind. The Kazakh government seemingly has little to lose and everything to gain when it comes to the economic trade route. It will allow Kazakhstan to realise its goal of becoming the primary transit hub between China and Europe, with Central Asia as the key land bridge between East Asia and critical markets in the West.

Fig. 7
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(http://www.orgs.miamioh.edu/silkroad/maps/maps.html)

“Old Silk Road” passing through Central Asia

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The potential rewards of the new “Silk Road Economic Belt” (Fig. 8) are far too great to prevent such a project from proceeding. The political will is too strong. Nevertheless, the environmental impacts of such a project are potentially very severe, especially in Central Asia where the five independent sovereign nations that emerged following dissolution of the Soviet Union have demonstrably failed to make any improvements to the appalling environmental management practices they inherited. The region’s water resources, a shared responsibility due to the transboundary nature of ground and surface water flows in Central Asia, continue to be abused and mismanaged.

Fig. 8
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(modified after: http://www.kiongroup.com/en/main/media_site/ms_markets/markets_detail_8320.jsp)

New “Silk Road Economic Belt”

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The natural rate of population growth has been significant in Central Asia (Fig. 9) and is expected to increase. According to the U.N., the population of Central Asia will grow by 15 % between 2010 and 2020, and by 2050, the population is expected to have risen by between 35 and 40 %. Most of this growth will take place in urbanised areas such as the Fergana Valley where birth rates are 3 children per woman in Kyrgyzstan, 3.7 in Tajikistan and 2.5 in Uzbekistan. Inevitably, this will place a further burden on the region’s limited resources, especially water.

Fig. 9
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(modified after: United Nations, Department of Economic and Social Affairs, Population Division (2015). World Population Prospects: The 2015 Revision, DVD Edition)

Natural population growth in Central Asia

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The new “Silk Road Economic Belt” may well bring jobs and prosperity to Central Asia, thus alleviating some of the social concerns. However, it will also accelerate population growth and demand for water and, given their records of the past 25 years, there can be no confidence that the governments of Central Asia have the capability to respond to increased water needs, especially in the face of climate change.

Changes are needed urgently. Water has long been a serious cause of conflict in Central Asia. In terms of their populations, Kyrgyzstan and Tajikistan have a considerable surplus while Uzbekistan, Turkmenistan and Kazakhstan argue they do not get their fair share of the region’s major rivers. Mistrust and tensions have always existed in the region, well before the Soviet occupation, and these must be adequately resolved if any progress is to be made. This is likely to be a slow process but as noted by ICG (2014), “water can be a driver of conflict but it can also be a driver of peace”. Investment in public education can go a long way to healing the problems of the past. The public needs to appreciate the need for equitable water resource management and understand the long-term benefits of dialogue, cooperation and constructive decision-making. As primary stakeholders in the region’s shared water resource, the public needs to have its voice heard. Although the transboundary nature of the region’s water resources makes equitable and sustainable management a forbidding task, the challenge is surmountable with a system of water governance that involves all stakeholders in the process.

Ultimately, good decision-making will depend on sound science and reliable environmental data. It is essential that groundwater and glacial ice, as the two largest stores of fresh available water in Central Asia be appropriately considered. Understanding their behaviour is the key to water resource management. Hydrological research in the Central Asian countries is currently limited, and reliable data are rarely accessible. In terms of the “Silk Road Economic Belt” project and its potential impacts on transboundary water resources in Central Asia, urgent research priorities include:

  • Detailed estimates of population projections and likely water and energy needs.

  • A complete assessment of the project’s potential environmental and ecological impacts, together with options for amelioration/remediation.

  • A full appraisal of the geologic hazards that may result from project activities and how they can be minimised.

It is also essential that environmental monitoring networks be established in areas likely to be affected by the project, well in time for pre-project, baseline observations to be made. With careful planning, adequate scientific research, good data, full involvement of stakeholders and the close cooperation amongst the nations involved, the new Silk Road Economic Belt can be developed in a sound and environmentally responsible manner.

Concluding discussion

The water resources of Central Asia have endured a long history of mismanagement. The problems began in the 1960s with the large-scale water diversion practices of the Soviet Union that set in motion the catastrophic demise of the Aral Sea. Unfortunately, there are no signs that the dissolution of the Soviet Union in 1991 has brought any improvements to water management strategy in the region. It is nearly 25 years since Central Asia’s water resources became the shared responsibility of five independent nations, but despite some collaborative efforts to improve water governance and develop appropriate transboundary water management policies, the unsustainable practices of the past 50 years persist, as have the predictable negative consequences.

Undermining any progress on water management are the divergent economic interests and conflicting needs, goals and priorities of the five Central Asian countries. Rivalry and deep mistrust between these proud countries remain an impediment to achieving the degree of cooperation necessary for constructive, water management and decision-making.

For many Asians, the recently proposed new “Silk Road Economic Belt” is seen as an immense opportunity to bring wealth and prosperity to some of the most impoverished regions of Northwest China and Central Asia. The project has received considerable international support and, in the long term, will inevitably achieve its ambitious economic goals. However, support is not universal, and questions are being raised, concerning the potential damage such a project could inflict upon the region’s sensitive environmental features, especially water. Given Central Asia’s long and continuing history of water mismanagement, there is little confidence that the project’s water needs can be adequately met. In effect, the new “Silk Road Economic Belt” and the rapid growth it will bring, represents a very significant long-term threat to the sustainable management of Central Asia’s transboundary water resources. The fundamental concern is that the project may place too great a burden on a water management system in Central Asia that is seriously dysfunctional and shows no sign of improvement.

The countries of Central Asia need to recognise that the economic success of the proposed new “Silk Road Economic Belt” hinges on their ability to develop programs that can ensure the region’s water resources are managed in a sound and sustainable manner. This will be an immense challenge and will require cooperation amongst the countries of Central Asia that goes far beyond what currently seems possible. External pressures from neighbouring Russia and China are likely required to make this happen. It also critical that the project be supported by sound science and good hydrological data; there will be a need to invest in scientific research in the relevant fields. With judicious planning, good science and a commitment amongst the nations of Central Asia to create a shared vision and collaborate towards a common goal, the “New Silk Road” can be developed both beneficially and sustainably.