Urban and rural groundwater use in Zhengzhou, China: challenges in joint management Ronglin Sun & Menggui Jin & Mark Giordano & Karen G. Villholth Abstract Groundwater plays an important role in the total water supply of much of China, particularly in the north. It has contributed substantially to both agricultural growth and urban and industrial expansion. However, overexploitation and poor management have contributed to infamous groundwater depletion problems and less publicized groundwater quality deterioration. One of the key challenges for China will be how to make groundwater use sustainable while still meeting increased food needs as well as the industrial and domestic demands of a rapidly urbanizing society. Zhengzhou City, one of China’s test cities for building a “water saving society” highlights both the difficulties and potential solutions to northern China’s joint rural and urban groundwater challenges. Based on secondary data and a primary survey of groundwater management in the region, this report provides an overview of Zhengzhou’s groundwater development and use as well as the ongoing institutional and policy reform processes within the water sector. The results highlight how a deepening of ongoing reforms, which simultaneously consider groundwater as an integral rural and urban issue and a fundamental economic and social asset, may improve groundwater outcomes, not only in Zhengzhou but in China, as the country’s economy and demography continue to change.

Received: 26 May 2008 / Accepted: 27 February 2009 Published online: 24 March 2009 © Springer-Verlag 2009 R. Sun ()) : M. Jin Department of Hydrogeology, School of Environmental Studies, China University of Geosciences, Wuhan, Hubei 430074, China e-mail: [email protected] e-mail: [email protected] Tel.:+86-27-62544251 M. Giordano : K. G. Villholth International Water Management Institute, P.O. Box 2075, Colombo, Sri Lanka e-mail: [email protected] e-mail: [email protected] Hydrogeology Journal (2009) 17: 1495–1506

Keywords Groundwater management . China . Urban and rural groundwater . Institution . Policy

Introduction As China’s population has grown and its economy changed, water demand and the relative location of that demand have changed with it. Total water use rose from an estimated 444 BCM—billion (109) cubic meters—in 1980 to 557 BCM in 1997 (Liu and Chen 2001) and remained at approximately that level to the present (555 BCM in 2004; MWR 2004). Over the same period, water use shifted away from agriculture (a fall in share from 83.4% in 1980, 70.5% in 1997, to 64.6% in 2004; Liu and Chen 2001; MWR 1997; MWR 2004). At the same time, the role of groundwater in overall use has increased from 14% in 1980 to 18.5% in 2004 (Liu and Chen 2001; MWR 2004). However, the role of groundwater is disproportionately high in urban areas and in northern China, the main grain producing area of the country. Of the 660 cities in China, more than 400 now rely on groundwater to some extent (MLR 2005). Five northern provinces—Hebei, Shanxi, Henan, Shandong, Liaoning—and the municipal region of Beijing, get more than 50% of their total water supply from groundwater. In the Hebei province, groundwater’s share is 81% (MWR 2002). For agriculture, it has been estimated that 68% of all irrigation water in northern China is now supplied by groundwater (Wang et al. 2007a). Although groundwater development has played an important role in the development and growth of agricultural production and associated food security in China and the more recent trend to an urbanized and industrialized society, improper or non-existent management has resulted in many problems related to the resource itself but with environmental and socioeconomic implications, including water-table decline, land subsidence, groundwater pollution and seawater intrusion (Jin et al. 2005). Moreover, with water demands of the cities continuously increasing simultaneously with sustained rural needs for irrigation to support the traditional staple food production (wheat and maize) in northern China, these areas are faced with the problem of satisfying urban as well as rural DOI 10.1007/s10040-009-0452-0

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needs. Recognizing the problems, governments at multiple levels within China are trying to improve water governance and management through changes in policy and project implementation. Since groundwater is the major overall source of water, there is a need to focus on this resource which traditionally has not received the same degree of attention as surface water in a management context. One of the major challenges is how to strike a balance between urban and rural use as a means to sustainable development based on integrated groundwater-surface water and urban-rural management principles. A first option when water stress is felt is to increase supply. The ongoing “South–North Water Transfer Project” is the most significant intervention and it is designed to resolve water shortage problems in the north of China by transferring water from the relatively water abundant south to the water-short north (Liu and Zheng 2002). The middle route would transfer water from the Danjiangkou reservoir on the Han River, which is a large tributary to the middle reaches of the Yangtze River, to Hubei, Henan, and Hebei provinces, and ultimately to Beijing and Tianjin. In the long run, it may also be necessary to divert additional water from the Three Gorges reservoir on the Yangtze River to the Danjiangkou reservoir to meet the large water demands of the northern provinces (Fig. 1). While the middle route of the transfer scheme can relieve water stress and conflicts in northern China, the volume is not sufficient to resolve the overall problem and the water will be used mainly for domestic and industrial water uses in urban areas and not to irrigate cropland (Kendy et al. 2007). To ensure that the water that is transferred gets efficient use, the Chinese government has also advocated demand management with a “first water saving, then transfer water” strategy, with water-saving policies issued in many cities. In 2005, the city of Zhengzhou (hereafter Zhengzhou), the capital of the Henan Province, became one of six declared test cities for building a “water saving society” amongst the 42 large cities that will receive water from the middle or east routes of South–North Water Transfer Project. To achieve the water conservation goals, many water saving technologies and policies for groundwater development control have been implemented in Zhengzhou. However, groundwater is still in a state of overexploitation and environmental problems resulting from groundwater development still exist. As Zhengzhou is a water-saving demonstration city and the larger municipal area includes substantial rural lands, the region exemplifies the issues in conjunctive rural and urban groundwater use and the rural-urban groundwater link faced by much of northern China. An examination of the issues of groundwater management in the region is instructive in understanding the challenges and potential solutions presenting themselves to the groundwater sector, and indeed the total water sector, throughout northern China. This report provides an examination of the key groundwater environmental, socio-economic and instituHydrogeology Journal (2009) 17: 1495–1506

tional issues and problems in Zhengzhou, and uses that examination to provide insights into how they might be solved. The study first gives an overall picture of groundwater development and use, as well as groundwater depletion and quality deterioration in both urban and rural parts of the area. It then provides an understanding of current groundwater policies and measures, how they differ between urban and rural areas, and how these differences impact groundwater management. Finally, potentially innovative and effective changes to integrated groundwater management and institutions in Zhengzhou are discussed and generalized to other areas of northern China.

Methodology This study is based on secondary data from Chinese language sources, interviews with selected officials as well as the results of a series of surveys of groundwater managers and users. Secondary data on groundwater resources, development and use as well as data on socioeconomic variables were taken from a variety of official Chinese statistical year books, information openly available on government websites, research reports of the Water Resources Bureau of Zhengzhou and China University of Geosciences. Information on formal groundwater policies and institutions was obtained both from documents issued by various levels of government as well as from semi-structured interviews with six government officials in the related water sector of Zhengzhou. Surveys of rural groundwater users, rural tube well managers (the farmers who are responsible for maintaining and operating one or more irrigation tube wells which belong to collective, other private owners or themselves), and village leaders were conducted in Dec. 2006–Jan. 2007. The surveys were performed predominantly in the mountainous counties of Xinmi and Xingyang, located in the plains region of Zhengzhou (Fig. 1). Ten villages in Xinmi County and 12 villages in Xingyang County were chosen using a stratified random sampling strategy. In each village, the village leader and two randomly selected tube well managers (in one village, only one) were then surveyed. In total, 22 village leaders and 43 managers were surveyed. The scope of the surveys was broad and interdisciplinary. The village leader questionnaires included information on social, economic and agricultural features, tube well development, water saving technologies, groundwater governance policies and implementation at the village level. The tube well manager’s survey focused on tube well management, water table change, groundwater extraction charges, drilling investments, crop patterns and the agricultural cost and income of the manager. The detailed results of the study are available in Sun et al. (2009) and are given here in summary form. DOI 10.1007/s10040-009-0452-0

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Water resources and economy of Zhengzhou Zhengzhou is located in the lower reaches of the Yellow River (Fig. 1). Its 7,446 km2 are made up of the city of Zhengzhou (about 14% of the area), the capital of Henan province (167,000 km2), and surrounding rural land (84% of area). Around 61% of Zhengzhou’s population of 7.2 million resides in rural areas (as of 2006; SBZ 2006). However, as in much of the rest of China, this is changing rapidly. From 2004 to 2006, some 400,000 people, or

14.3% of the urban population, migrated to the city. The decline in rural population has been matched by a decline in agriculture’s share of total employment, which has fallen from 37.1% in 2002 to 29.2% in 2006 (SBZ 2006). Nonetheless, total agricultural output of the area has continued to increase, with an average growth rate of 14% from 2002 to 2006. This perhaps surprising outcome and its implications for water and agricultural policy are discussed in the following. While agriculture has grown, other sectors have grown even faster, and the agricultural

Fig. 1 Schematic map and depression cones of Zhengzhou

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share of total output has fallen from 17.3% in 1980, to 5% in 2002, and 3.8% in 2006 (SBZ 2006). Main crops grown in the area are single cropping of wheat and maize. The growth in the overall economy as well as the differential growth rates between the urban and rural economies have generally been reflected in the water use. From 1980 to 2004, total water use increased by 69% though this rise covers an initial major increase up till 1995, followed by a slower decrease (Fig. 2a). While there has been some fluctuation in agricultural water use depending on rainfall conditions (e.g. 1995 and 1997 were drought years), major increases in overall use has come from the industrial and domestic sectors, with use by each sector more than tripling and agriculture’s share consistently falling. As living standards and urbanization continue to rise, domestic water use will likely continue to increase. However, water saving technologies have been able to stabilize industrial demand in recent years. Zhengzhou is located in the water-short region of northern China with a mean annual precipitation of 641 mm. Based on water-balance calculations for 1956– 2000, mean renewable freshwater resources (from surface and groundwater) are 1.32 BCM/year, corresponding to a per capita water availability of only 199 m3 per year (not including the allocation from the Yellow River). This is 8.9% of the average water availability for China, 2.2% of global averages, and one fifth of the 1,000 m3 per year, per capita cut-off defining water-scarce conditions (Falkenmark et al. 1989). Zhengzhou is supplied by 124 rivers, the single most important of which is the Yellow River which crosses the area on its northern border (Fig. 1) and supplies water from more upstream catchment and discharge areas. However, the quality of the water in these rivers is often poor. Increased domestic water use due to rapid urbanization and increasing living standards has also dramatically increased the volumes of wastewater, typically discharged untreated back into the rivers. From 2000 to 2005, annual domestic wastewater increased from 15,970 to 23,144 tonnes (EPBZ 2006). In addition, growth in the industrial sector, and intensification in the crop and livestock agricultural sub-sectors have also added to the contamination of water bodies. As a result, most surface water in the area is only applicable to agricultural use and

Groundwater depletion and quality deterioration Though here has been a slight reduction in groundwater abstraction in the last decade, a primary problem related to groundwater use in Zhengzhou is overdraft. Based on groundwater balance calculations from data between 1980 and 2000, annual exploitable groundwater resources (the amount of water that can be abstracted annually from a given aquifer under prevailing economic, technological and institutional constrains and environmental conditions; here it is calculated based on annual renewable resources) in Zhengzhou are 0.94 BCM (WBRZ 2006). As indicated in Table 1, actual groundwater use has been near or above this level since 1995, i.e. groundwater is in a state of overexploitation. Although the total groundwater use is less than 0.94 BCM in other years, in some places, especially in urban areas or other intensive pumping areas, the groundwater use exceeds that of the local exploitable resources.

b

1.8 1.5

Water use (BCM)

a Water use (BCM)

Fig. 2 Water use in Zhengzhou by a source and b sector

not to centralized sources of drinking water and industrial use. Overall, groundwater use in Zhengzhou has increased by more than 50% over the last quarter century, with the largest increase over the years 1980–1995 (Fig. 2a). Since then, a slight decrease is observed as agricultural water use has decreased (Fig. 2b). Groundwater’s share of the total water supply has decreased slightly over the years but in 2004 still accounted for 70%. However, in some counties (e.g. Xingyang), groundwater accounts for more than 90% of the total use (Sun et al. 2009). In the last decade, the share of agricultural water supplied from groundwater has been on average 69% of the total agricultural water use (Table 1). While the proportion of water being diverted to agriculture has declined, the agriculture sector is still the largest user of groundwater and groundwater share in agriculture is increasing (Table 1). Groundwater use in agriculture has been driven by its ease of use with new drilling and pumping technologies, the convenience of self-supply from local wells and government support to such development, in the form of funding. Moreover, for agriculture and industry, most of water is supplied by groundwater.

1.2 0.9 0.6 0.3 0

1.8 1.5 1.2 0.9 0.6 0.3 0

1980

Total

1985

1990 1995 Year

Surface water

2000

2004

Groundwater

1980

1985 Total Industry

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1990

1995 2000 Year Agriculture

2004

Domestic

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GW use in BCM and sectoral share (%) Total Agriculture Industry

Domestic

Water use by sector in BCM and GW Share (%) Agriculture Industry Domestic

1.05 0.89 0.96

0.12 (11.2) 0.13 (14.6) 0.17 (17.4)

0.96 (62.3) 0.80 (67.7) 0.64 (76.3)

0.60 (57.7) 0.54 (60.9) 0.49 (51.5)

0.33 (31.1) 0.22 (24.5) 0.3 (31.1)

The result of this overexploitation has been a decline in water tables. From 1990 to 2000, tube well numbers in urban and rural areas rose from 37,164 to 42,763 (WBRZ 2006). The drop in water tables has meant decreased yields or outright abandonment of tube wells and a shift from shallow to deep tube wells. For example, in Xingyang County, around 100 irrigation tube wells were abandoned each year from 1993–2003 (Sun et al. 2009). However, in 1997 when rainfall was lowest in the last two decades, a large amount of groundwater was pumped, and nearly 800 wells were abandoned. As a result, farmers drilled new deep tube wells. Thus, while the total operational tube well number stayed nearly constant, the proportion of deep tube wells increased from 50 to 76% from 1993 to 2003 (Fig. 3). Most of the new deep tube wells were funded by the government or village collectives. In addition to a general decline in groundwater levels, there has also been an increase in the number and area of depression cones (the area around a discharging well or group of wells where the hydraulic head in the aquifer has been lowered locally due to pumping). According to data from 2005, there were 16 pumping cones in Zhengzhou covering a combined area of over 500 km2 (Fig. 1). Most of these pumping cones are located under urban areas indicating that groundwater extraction in cities is very intense and concentrated. In addition to depletion, groundwater in the Zhengzhou region has also suffered from degradation in quality. In most middle and deep aquifers, the groundwater has not been polluted. In the shallow aquifers of the mountainous area, most of groundwater is applicable to centralized sources of drinking water and agricultural and industrial use. However, in the shallow aquifers of the plains area, most groundwater is not applicable to centralized sources

Number of tube wells

7000 6000 5000 4000 3000 2000 1000 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Total

Year Deep well

Shallow well

Fig. 3 Tube well development in Xingyang County, Zhengzhou, China (1993–2003) Hydrogeology Journal (2009) 17: 1495–1506

0.39 (84.5) 0.38 (58.3) 0.38 (78.6)

0.24 (50.0) 0.27 (47.6) 0.35 (48.2)

of drinking water and only to agricultural and industrial use and locally groundwater is not applicable to any purpose with respect to iron, manganese, chloride, fluoride, and bacteria (WRBZ 2005). The pollution sources include wastewater from industry and domestic sewage, as already mentioned, as well as agricultural fertilizer and pesticide application and wastewater from livestock. According to a report on drinking water safety in rural areas of Zhengzhou (WRBZ 2005), 1.5 million farmers (38% of all farmers) do not have access to safe drinking water from ground or surface sources. To remedy this problem, the government has initiated technical solutions, e.g. a project to dig 63 new public deep tube wells in rural areas to yield high-quality groundwater in 2005.

The institutional and policy environment for groundwater management Groundwater institutions To deal with water problems in general, various levels within the Chinese government have put in place a variety of evolving institutions and policies. Nationally, before 1998, the former Ministry of Geology and Mineral Resource had primary responsibility for groundwater management and the Ministry of Water Resources had primary responsibility for surface-water management. After reforms in 1998, followed by a 2002 modification of the 1988 water law, the Ministry of Water Resources has the single authority for water administration and supervision throughout the country (Feng et al. 2006). However, in practice, the Ministry of Water Resources is not the only government institution responsible for water. Water administration is shared by at least nine ministries at state (national) level: the Ministry of Water Resources, the State Environmental Protection Administration, the Ministry of Construction, the Ministry of Agriculture, the State Forest Bureau, the State Electric Power Company, the State Reform and Development Commission, the Ministry of Communication, and the Ministry of Health (Feng et al. 2006). Under these nine ministries, there are their subordinate bodies at the local level (province, city and county). Not surprisingly, these ministries and agencies have many overlapping functions. Specifically for groundwater, the Ministry of Land and Resouces also has the function of supervising hydrogeological exploration and evaluation, supervising the monitoring and prevention of over-extraction and contamDOI 10.1007/s10040-009-0452-0

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ination of groundwater, and protecting the geological environment. Under the Ministry of Land and Resouces, there is the China Geological Survey and an Institute of Geological Environment Monitoring in each province to investigate and monitor groundwater. The Ministry of Construction and its bodies at lower levels of government have the function of supervising groundwater development and protection in urban areas. At the same time, the State Environmental Protection Administration is responsible for monitoring, control and treatment of groundwater pollution. The functions and responsibilities of these ministries are not clearly separated and only limited communication and cooperation exist between them. As at the national level, there have also been institutional reforms at the level of Zhengzhou Municipal Area with a goal to merge water management. In 2002, the administrative management of groundwater, which was previously the responsibility of Zhengzhou Municipal Coal Administration under the former Ministry of Geology and Mineral Resource was handed over to the Water Resources Bureau of Zhengzhou (WRBZ). In the same year, urban groundwater development and protection functions that were previously the responsibility of Zhengzhou Municipal Public Utility Adiministration (ZMPUA) were handed over to WRBZ. In 2004, the water-supply and water-saving offices under ZMPUA were handed over to the WRBZ. In principle, all management of water resources was then united. Based on interviews with experts and practitioners in the area, it is clear that, like at the national level, the institutional reform has not meant that all administration related to groundwater has been unified in practice (Table 2). In addition to the WRBZ, the Environmental Protection Bureau of the City of Zhengzhou and its underlying bureaus at county levels are charged with water quality and pollution control in Zhengzhou. The Municipal Bureau of Zhengzhou is responsibe for urban water drainage and wastewater disposing. The Henan Institute of Geological Survey and the Henan Institute of Geological Environment Monitoring under the Ministry of Land and Resouces also carry out monitoring and investigate groundwater. Unfortunately, communication

and data sharing amongst the different agencies suffer because of unclear mandates and conflicting interests. Even within the WRBZ, groundwater management functions have not been united. For example, urban and rural management are separated with the Water Resources Management Office (also called Water Supply and Water Saving Office), mainly responsible for urban groundwater management and the Office of Irrigation, Drainage and Rural Water Supply mainly responsible for rural groundwater management. Separate or uncoordinated management between rural and urban areas, water quantity and quality, surface water and groundwater, water allocation and pollution control challenges reasonable and sustainable groundwater management.

Groundwater policy In China, there is no special groundwater legislation at the national level and existing water legislation is imprecise and inadequate in dealing with groundwater issues. However, at the local level, there are numerous policies and written guidelines on how groundwater should be managed and used. Many of these policies are related to water pricing, the use of water-saving technologies, and the control of groundwater development. As will be shown, most of these policies focus primarily on groundwater management in urban rather than rural areas. In Zhengzhou, from 1996 to the present, the price of water supplied in urban areas has increased by 3~6 times. To assist the measuring of domestic water use, a “one water meter per family” project is being implemented. Once complete, a “ladder price” (progressive water pricing) policy will be implemented. Before this project, most families paid a flat rate irrespective of volume of use. In addition, in order to relieve groundwater depletion and perform united groundwater management, the government is trying to shift use from locally derived groundwater to the municipal system through a groundwater development control policy (discussed later) and water pricing policy. For example, as shown in Table 3, the price of domestic water supplied by the municipal system is lower than private groundwater pumping. However, for all other

Table 2 Groundwater management institution in Zhengzhou Departments

Water resources management functions

Groundwater management functions

Water Resources Bureau of Zhengzhou

Joint water resources management

Environmental Protection Bureau of Zhengzhou City Zhengzhou Water Supply Corporation

Water quality and pollution control

Groundwater development, protection Groundwater monitoring

Henan Institute of Geological Environment Monitoring Municipal Bureau of Zhengzhou Yellow River Conservancy Commission

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Water supply system Estimation and monitoring of groundwater Water drainage system construction, river channel reclamation, waste water disposal Allocation of Yellow River water resources

Manages three groundwater abstraction plants Groundwater monitoring -

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Table 3 Water prices in Zhengzhou in urban areas in 2007 (US $/m ) Water supply

Domestic

Industry

Service industrya

Municipal (tap water either from surface or groundwater) Private (from wells within municipal area)

0.30 0.33

0.37 0.33

0.51 0.44

a

Service industry means the catering sector and construction industry Data source: author interviews

sectors, the price of privately supplied water is still lower than that of municipally supplied (Table 3). In addition to providing price incentives to reduce urban groundwater use, the local government is also trying to reduce use by direct control. In 2002, the local government issued a regulation to close private tube wells in urban areas which fall under the responsibility of the water supply and water saving office under ZMPUA. According to the regulation, tube wells in areas of declining water tables and in seriously polluted areas should be backfilled or closed permanently without compensation. Other tube wells would be purchased by Zhengzhou Water Supply Corporation and closed except for meeting an emergency need under the management of WRBZ. However, the implementation of this policy is still challenging. The government’s goal was to close all the private tube wells in urban areas by 2005. Since the water supply and water-saving office was handed over to the WRBZ in 2004, the implementation of the regulation was delayed. By 2006, 804 private tube wells had been closed by the government and their users supplied with municipal tap water. However, there are still more than 400 private tube wells operating which account for most urban groundwater pumping (WRBZ 2006). Concurrently, new tube wells deeper than 700 m have been built under the authorization of other government agencies or without authorization. In addition to policy measures and regulations, the government is also promoting water-saving technologies in urban areas. Many water conservation technologies such as low-flush toilets, faucets, showerheads, and car washing equipment, have been widely adopted for domestic use. Adoption of such measures is driven by the savings incentives of the users and significant public promotion. The result has been that, while living standards and urban population have increased rapidly, the domestic water use per capita has actually decreased. For example, the mean domestic water use per capita in urban area, which was 168 L per day in 1995, had declined to 155 L per day in 2006. Now, governments are trying to upgrade the water supply system to reduce conveyance water losses in municipal systems, propagate rainwater-harvesting technology, and improve the sewage networks to improve wastewater capture and treatment. Water-saving technologies have also spread in the industrial sector. The water use by that sector has stabilized at 0.38 BCM/year (Fig. 2b), despite a rapid increase in industrial output. However, in rural areas where most water use is still occurring and most derives from groundwater, there are few corresponding policies to encourage farmers to save Hydrogeology Journal (2009) 17: 1495–1506

groundwater. For example, while farmers do have to pay the energy costs associated with groundwater pumping, they do not pay a fee for the water resource. In 2005, the electricity tariff for irrigation was 0.087 US $/kWh in Xinmi County and 0.078 US $/kWh in Xingyang County (Sun et al. 2009). Based on only the electricity charge, the cost of rural groundwater is only about one third of that of urban groundwater by volume. These low water use prices coupled with apparently limited awareness of the groundwater issues mean that farmers have not taken active measures to address groundwater depletion, despite the well abandonment already discussed. According to the questionnaire survey in 2006, only 17 of 43 tube well managers (all farmers) said that they knew that the water table was declining. Of those aware of the problem, most said they would respond by seeking new supplies, not by conserving existing supplies. All said they would drill new tube wells, 11 said they would change the pump to a more powerful one, and only two managers said they would adopt water-saving irrigation. Nobody replied that they wanted to adjust cropping patterns (Sun et al. 2009). This is generally consistent with published figures on water-saving technology adoption. For example, in 2005, only about 26% of the total arable area applied some water-saving technology (of the 85,947 ha, 73% use pipe conveyance, 18% have canal seepage control, 8% use sprinklers irrigation and 1% use micro irrigation; NBSC 2006). The village leader questionnaire surveys in 22 villages show that basic practices and technologies with relatively low cost and ease of use but with low field level water-use efficiency such as furrow irrigation, border irrigation and conservation tillage are most widely used (Sun et al. 2009). In order to improve water conveyance and distribution efficiency, pipe conveyance has been applied in some areas, funded by the government. For example, underground pipe conveyance systems were built to replace earth canals in eight villages of ten village samples of Xinmi County. In Xingyang County, only two villages of 12 village samples use underground pipes, probably because these government funds are not available. Those underground pipes in place are funded by village collectives. To promote micro irrigation technologies (e.g. sprinkler and drip irrigation), a few demonstration areas have been set up by the government since 2000. However, there are two main reasons for limited farmer adoption of advanced irrigation technologies. Firstly, the high costs compared to farming income. The capital cost of sprinkling systems are 1,557–1,940 US $/ha while the costs of underground pipe DOI 10.1007/s10040-009-0452-0

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conveyance and delivery systems are 57–77 US $/ha. In comparison, farmers’ net income from the wheat-maize cropping pattern is about 1,214 US $/ha/year from cropping (Table 4). Secondly, the farm family’s lands are generally small and scattered. Arable land per capita is less than 0.065 ha in most villages of Xinmi and Xingyang (Sun et al. 2009). One family of five persons can have about 0.325 ha arable land, often divided into small pieces scattered in different places, partly as a result of past land-tenure policies aimed at equally sharing different quality lands between farmers. These conditions make application of many water saving technologies such as sprinklers, difficult. Secondly, local governments have not paid sufficient attention to the extension of advanced water-saving technologies in rural areas. Initial adoption of new technologies requires extensive funding, yet agriculture accounts for a little fraction of the overall gross domestic product (GDP), about 3.8% (SBZ 2006). Furthermore, no mechanisms have been implemented for maintaining the water-saving technologies already adopted. Much of the water-saving technology, which has been funded by the government, is no longer functioning with the classic cycle of build–deteriorate–rebuild–deteriorate being common in the 1990s. Mechanisms to ensure adequate operation and maintenance of government funded infrastructure are needed if such investments are to meet their water saving goals. In terms of policies to control groundwater development, two are of particular interest: the water abstraction licensing policy of the central government and the policy to close private tube wells in urban areas made by the Zhengzhou government. On 1 August 1993, the Chinese government issued a “water abstraction licensing” regulation requiring groundwater users to obtain a waterabstraction licence. Under the regulation, those using a small quantity of groundwater for irrigation and those using groundwater to combat drought were exempt. On 21 Feb. 2006, the Chinese government issued a modified regulation: “the administration of water abstraction licensing and collection of water resources charges”. Under this regulation, only those using groundwater to combat the effects of drought were exempt. Under both regulations, all tube wells for normal agricultural use in rural areas and all groundwater users in urban areas require a license. As the central government of China issued many guidelines to promote further agricultural reform and rural economic development in recent years, the local government under the Ministry of Water Resources thinks that the imple-

mentation of the water abstraction policy may increase the pressure on farmers to undertake action that will conflict with central guidelines. So, “water abstraction licensing” has not been really implemented. However, in urban areas, this policy is carried out more strictly and most of the tube wells are licensed.

Policy discussion of joint rural and urban groundwater management The essential goals behind the water-savings efforts of government agencies at all levels in the Zhengzhou are admirable. For example, the Zhengzhou government’s 2006 “building a water-saving society” regulation envisions more efficient water use and more savings in the domestic, industrial and agricultural sectors, higher water productivity and much higher water reuse efficiency (PGZ 2006). At present, local water availability is 1.32 BCM/year to which can be added 0.43 BCM/year from the Yellow River allocations. In addition, Zhengzhou is planned to be allocated 0.5 BCM/year from the South–North Water Transfer Project in 2010. By 2010, Zhengzhou’s total water availability may thus be 2.25 BCM/year. The goal of total water use is 1.65 BCM by 2010 and not more than 2.00 BCM by 2020. Under these scenarios, domestic, industrial and environmental water uses are to increase while agricultural water use will decrease despite an increase in irrigated area due to higher water productivity. In recent years, total water use has already approached the 2010 goal and total availability is only slightly higher than the 2020 goal even if the Yellow River allocation and planned south–north allocation are fully utilized. As the economy continues to grow and population increases and urbanizes, demand for water resources in general and groundwater in particular will continue to climb. The growing understanding of the need to maintain environmental reserves and flows will only add to these pressures. Current projections of environmental needs are 0.20 BCM in 2010 and 0.37 BCM in 2020 or almost one fifth of total projected use (CUG 2007). To sustainably balance future groundwater supply and demand while improving the environment and meeting other policy goals, in particular rural income growth, will require changes in the way groundwater is currently governed and used. Based on the analysis here of existing use and management patterns, six areas are reviewed, in which reform may prove most fruitful in sustainably managing

Table 4 Cropping cost and income per ha of farmer in wheat-maize system Crop

Productivity (kg)

Crop price (US$/kg)

Gross income (US$)

Irrigation (US$)

Seed (US$)

Fertilizer (US$)

Pesticide (US$)

Others (US$)

Crop cost (US$)

Net income (US$)

Wheat Maize

6198.0 6873.6

0.18 0.15

1109.1 1035.4

60.9 45.9

54.8 62.2

217.6 196.4

33.6 31.3

115.9 107.8

485.4 445.9

623.7 589.6

Data source: average values of 43 tube well managers’ questionnaire survey Hydrogeology Journal (2009) 17: 1495–1506

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groundwater and contributing to Zhengzhou’s overall water goals.

Coordinating groundwater management While in theory all water-resources management including groundwater should be under the Ministry of Water Resources and its provincial and local arms, the reality in China, as in much of the rest of the world (Nanni and Foster 2005), is that management is scattered amongst a host of agencies. Insufficient communication and sometimes conflicting interests have resulted in groundwater regulations and policies being ineffectively implemented, or even conflicting. For example, as described, one agency is working to close urban tube wells while others continue to open new wells. Building some “ideal” state of truly integrated groundwater management is unrealistic in both the short and long terms. However, building institutional frameworks under which ministries and agencies with differing mandates and goals can share information on the state of groundwater resources and the impacts of use, ultimately generating at least partial coordination of policies for groundwater management, is not. Within Zhengzhou, the Water Resources Bureau of Zhengzhou might serve as a focal point for communication and coordination of the groundwater functions of the other various actors involved in the areas of groundwater management.

well be taken from larger rivers like the Yellow River. A gain may be obtained from using more surface water, and indeed treated wastewater for agriculture while prioritizing groundwater for urban uses. Treated wastewater may be infiltrated in the cities to reduce depression cones and provide storage and buffering of the resource. However, environmental flows still need to be considered. Jointly prioritizing management of urban and rural groundwater may also reduce the overall costs of groundwater management. Most management efforts are now focused on the urban areas where a minority of use takes place. This is granted on the grounds that relatively higher economic output is derived from the cities. However, a proportionately higher gain may be obtained from investing in water saving technologies and cropping reforms in rural areas that could lead to real water savings that in turn could be benefited from for urban water supply. To address the issue of large depression cones around major cities, groundwater for urban water supply would have to be drafted from dispersed well fields, acknowledging the need for wider distribution nets than are used today. The marginal impact of additional institutional and policy reform may be greater in rural areas. While problems such as pumping cones and quality declines are more severe in urban areas, a failure to address issues in rural areas of Zhengzhou will eventually have implications for the success of urban groundwater management efforts. The important point is to consider the aquifer as a groundwater management unit which includes both urban and rural areas.

Joint urban and rural groundwater management Just as there are clear advantages to coordination of overall water-management agencies, there are also advantages to jointly considering rural and urban groundwater use within those agencies, as well as surface and groundwater interaction. Surface-water pollution from the industry and domestic wastewater discharge is severe enough that most river water in smaller rivers in the region cannot be used for irrigation. Partly in response, farmers shift to groundwater. Although the total agricultural water use has decreased slightly in the last decade, groundwater’s share of that use has increased from 62.3% in 1995 to 76.3% in 2004 (Table 1). Though there may be several reasons for this (including better drilling and pumping technologies), recognizing urban surface-water pollution as a push to rural groundwater use is one step forward. Wastewater treatment and re-use of domestic and industrial wastewaters for irrigation in rural areas is a means to improve environmental conditions and at the same time limit strains on groundwater. In reality, surface water, quality-wise if not polluted, is more appropriate for irrigation purposes, while groundwater, due to its relatively good quality is better used for domestic and industrial purposes (Villholth 2006). However, the trend in reality is the reverse, due to structural and practical reasons, e.g. the farmers find it very convenient to draft groundwater at their own will close to their field, while water intake for central municipal water-supply distribution systems may Hydrogeology Journal (2009) 17: 1495–1506

Increasing groundwater supply In addition to large-scale projects such as the South–North Transfer, smaller scale possibilities for increasing local water supply also exist. For example, rainwater harvesting, increased conjunctive management of surface water and groundwater, and groundwater recharge with reclaimed water are all possible methods for increasing and ensuring stable supply. The government has already begun efforts to spread rainwater-harvesting techniques with a few demonstration areas constructed in both rural mountainous areas and in urban areas. As Zhengzhou is located in a continental monsoon climate, about two thirds of rainfall is between June and September with major runoff events occurring over concentrated periods of a few days. In urban areas, this plentiful rainwater is lost to the area through discharge into the sewage drainage system. In rural mountainous areas with high gradients, most rainfall quickly discharges to streams and much is lost to the region. The use of rainwater harvesting to directly recharge aquifers or for above-ground storage for use in the dry season to indirectly reduce pressure on groundwater may be a supplementary groundwater management tool. Similar to the challenges of managing direct rainfall will be the management of supplies from the middle route of the South–North Transfer Scheme. The flood season and dry period in the source area of the middle route (the DOI 10.1007/s10040-009-0452-0

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Han River) are synchronous with that of the water use areas including Zhengzhou. As with local flood water, it will be necessary to store the transferred water for use in the dry season if the benefits of the transfer are to be realized (Sun et al. 2005). Reclaiming wastewater and possibly recharging it to groundwater (US EPA 2004), as mentioned, is another related option, and one test project with reclaimed water was scheduled to begin in Zhengzhou in 2007. At present, most wastewater from industrial and domestic use is discharged directly into rivers without treatment. Successfully treating wastewater reduces farmers’ and other’s need to switch from surface to groundwater. Recharging the reclaimed water obviously directly increases groundwater supply. The overall goal of the Government of Zhengzhou is to capture 75% of wastewater in cities by 2010 and to treat 98% of the captured wastewater. Whether or not such targets are realistic for Zhengzhou can be discussed. However, moving towards better management of wastewater will have direct benefits for groundwater management.

Changing cropping patterns and adapting water saving technologies The continued growth of the urban sector and its higher levels of water productivity are likely to draw water away from the agricultural sector in Zhengzhou, as elsewhere in China and the world (Barker and Giordano 2007). This will make it all the more difficult for rural farmers to maintain and increase their living standards, and for a major government policy goal to combat excessive urbanization and secure food production. Fortunately, farmers have already shown that they can increase the value of farm output without increases in water use. In recent years, this has largely come through shifts in cropping patterns. For example, the share of field crops in total agricultural output in Zhengzhou dropped from more than 70% in 1990 to just over 50% in 2005 while livestock increased from 22 to 43% over the same period (SBZ 2006). Within field crops, the area sown to lower value grains decreased from 0.43 to 0.36 million ha while the higher valued cash crop area increased from 0.09 to 0.16 million hectares over the same period (SBZ 2006). An efficient market linkage from rural to urban areas supports the ability of farmers to continue to shift to the most profitable crops and is one way to maintain farm income without additional water. This is more feasible in areas such as Zhengzhou in which a ready and close market exists for high-value perishable foods. It may be less feasible in more remote regions. At the same time, many high valued crops require more advanced water control technologies, technologies often associated with water savings. Evidence from urban areas of Zhengzhou has already shown that use of water savings technologies can reduce demand despite increased economic activity. The challenges in spreading micro-irrigation technologies, for example drip and sprinkler irrigation, have already been discussed. Updating surface Hydrogeology Journal (2009) 17: 1495–1506

irrigation technologies by proper scheduling of irrigation and adopting proper method of irrigation, like effective land leveling, popularizing narrow border irrigation and tiny-stream furrow irrigation through setting reasonable furrow and strip specifications and field natural slope, may be more appropriate and cheaper options.

Reforming water price policies within limits Water pricing can have a direct impact on water use and the adoption of water-saving technologies as shown for the industrial and domestic sectors in Zhengzhou. It is already planned to further increase domestic prices. Price increases (or, more generally, pricing) have also been advocated by some researchers for rural areas. However, it has been estimated elsewhere that the ratio of irrigation (pumping) cost to total cost for surface irrigation in healthy systems should be between 3 and 4% and should be lower than 10% in groundwater irrigated areas (Bos et al. 2005). Groundwater irrigation costs already account for 11.5% of the crop cost of the wheat-maize system in Zhengzhou (Table 4). While the costs of groundwater access are lower in rural areas than urban, raising them will likely cause some farmers to give up irrigation, at least for field crops. This would result in a reduction in farm incomes, defeating a major policy goal of the government. However, at least two possibilities exist under which pricing may both increase water-use efficiency and protect farm income. The first is to facilitate the shift out of field crops and towards high-valued crops as already mentioned. The second is to give farmers an opportunity to benefit from increases in water prices by allowing them to sell “their” water. In large parts of northern China, groundwater markets have begun to emerge in recent years as a way for many producers in rural China to gain access to groundwater and to earn additional income (Wang et al. 2007b). This development has been facilitated by the expansion of private, as opposed to collective, tube wells. However, according to the survey of Zhengzhou reported here, collective tube wells still dominate and comprise 95.9% of the total (Sun et al. 2009) in comparison to an average of 30% over most of the North China Plain (Wang et al. 2007b). The development of groundwater pricing and the ability of farmers to benefit from that pricing through water markets in which they have a stake is one way farm income can be at least partially protected while at the same time providing incentives for more efficient agricultural water use. However, clearly defined and legal water rights of water operators and users are the foundation of water markets (Yang et al. 2003). Otherwise farmers selling “their” water through groundwater markets may increase overall abstraction.

Real water savings, user adaptation and institutional needs As has been highlighted for other regions, the nature and value of the impact of many of the groundwater solutions proposed here depends on the scale of analysis (Loeve DOI 10.1007/s10040-009-0452-0

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2004). Many may result in increased supply or savings for Zhengzhou but not for the Yellow or Huai River Basins or China as a whole and thus not result in “real” water savings. For example, runoff from Zhengzhou which enters the Yellow River and a tributary of the Huai River is eventually used by others further downstream. Increases in Zhengzhou’s ability to capture water falling through rainwater harvesting within the area is in effect a decrease in water supply elsewhere. Since virtually all of the Yellow and Huai Rivers’ waters are used, the increase in Zhengzhou’s capture is effectively a loss for some other region. For areas in which water is already highly developed and scarce such as Zhengzhou and its Yellow and Huai River Basins, the need to coordinate water management and water-management investments at the regional scale is clear (Seckler 1996; Nogués and Herrero 2003). Another important consideration is that users adapt to new technologies. Many water-savings technologies work because they increase the productivity of water, allowing less to be applied for a given output. However, increasing the productivity of an input does not per se result in water savings. The classical example being that the water saved by using efficient irrigation methods (e.g. sprinkler irrigation) results in increased irrigated areas thereby maintaining an unwanted status quo in the water consumption. Thus an increase in water productivity can actually result in an increase, rather than a decrease, in overall water use unless there are institutional measures in place to constrain use (Ahmad et al. 2007). Thus, for any proposed change, it is important to study both how much room for “real” water savings there is and how the institutional, social and economic environment surrounding any change will affect the behavior of water users in order to determine the feasibility of any hopes for improvements. Although there are many suggestions about how to achieve good groundwater management from the social, economic, legislative and institutional aspects, increasing public awareness on groundwater by public education is the most important means as groundwater is an invisible resource (Jac 2007; Villholth 2006).

Conclusions Groundwater plays an important role in China and accounts for nearly 19% of the total water use. In northern China, groundwater accounts for more than 50% of the total water use. This use has helped to ensure the rapid development of the economy, urbanization, increased living standards and the conversion of this region into China’s food basket. However, there are now serious questions about the sustainability of groundwater as a base of continued growth. Cones of depression are forming in urban areas, regional decline in water tables is common, and water quality is deteriorating. In the water-scarce environment of northern China, the growth of high income urban centers is drawing water away from the relatively poor rural areas, which provide China’s basic food supply. These challenges will persist as China’s Hydrogeology Journal (2009) 17: 1495–1506

economy continues to transform and urbanize. The case of the Zhengzhou municipal area, with a urban heartland and surrounding rural areas, provides a case study in both the problems and opportunities in trying to manage China’s groundwater future. Groundwater use in Zhengzhou has increased by more than 50% in the last quarter century, and at present it accounts for 70% of the total water use. Regional watertable decline, extensive depression cones in urban areas and groundwater pollution indicate extensive groundwater over-exploitation and mismanagement. Shallow tube wells have gone dry and been abandoned, and more and more groundwater users are drilling deep wells to access more abundant and good quality deep aquifers. The pressure for farmers to access groundwater has also been increased by the pollution of surface water from urban and industrial sources resulting in a rising share of groundwater in total use. Already use is beyond sustainable levels. A number of promising efforts to improve groundwater management in Zhengzhou are underway. However, they appear insufficient to meet the rising water challenges. Separate management between urban and rural areas, surface water and groundwater, water quantity and water quality make sustainable groundwater management still challenging. This report has outlined six areas for consideration to make the reform efforts more successful. First, while the creation of a single groundwater agency is not practical, increased coordination of ministries and agencies responsible for groundwater is a possible and necessary step to increase policy effectiveness and avoid policy inconsistency. Second, and related, joint consideration of urban and rural groundwater management can both increase opportunities for groundwater solutions, help to prioritize policy efforts, and optimize the resources invested. Third, opportunities for supply increase still exist from reclamation and reuse of wastewater, rainwater harvesting, groundwater recharge with reclaimed water and better conjunctive management with surface water and storage. Fourth, changes in cropping patterns and the use of rural water-saving technologies can both help to protect farmer incomes and increase rural water productivity. Fifth, changes in water pricing policies may help to reduce rural water use as has already happened in urban areas. However, additional measures will be necessary if price increases are not to adversely impact farmers and jeopardize poverty alleviation policies. And finally, for any suggested change in groundwater policy and management, it is critical to understand how much of the impact will result in “real” water savings rather than simply a reallocation of existing supply. Besides, increasing public awareness on groundwater is the most important pathway to good groundwater management. Acknowledgements The authors gratefully acknowledges P.G. McCornick for his insights and helpful suggestions, Q.K. Han in WRBZ for his support in the field survey and providing data, Y.F. Liu and Y.P. Qian for the questionnaire survey work in Zhengzhou, and the International Water Management Institute and the Challenge Program on Water and Food for the funds supported to this research. The authors also acknowledge the funding from Hi-tech Research DOI 10.1007/s10040-009-0452-0

1506 and Development Program of China (863 Program, No. 2007AA06Z337) and from China Postdoctoral Science Foundation (Program No. 20070420938). The authors are also grateful to the three reviewers and the editors for their much appreciated and constructive comments.

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DOI 10.1007/s10040-009-0452-0