BEIJING’S DEVELOPMENT RESTRICTED BY WATER RESOURCES 

Zhang Xin

China Agriculture University

P.O. Box 54, China Agricultural University (east campus), Beijing 100083, China

Tel: +86-10-62323995 / 62336533

E-mail zhangxin0530@sina.com

Abstract: The relationship between Beijing’s development and water resources is discussed. Based on analysis of historic and present conditions of water shortage, it is presented that bearing capacity of water resources must be taken as an important constraint condition of the city development planning in the future. It is found out that the development and utilization of the local water resources has approached to the limit bearing capacity of water resources by analyzing the level of development and utilization of water resources; and it is suggested that the development scale and speed of economic growth of the city should be controlled strategically in the light of sustainable utilization of water resources.

Keywords: water shortage, bearing capacity of water resources, constraint condition, sustainable utilization, sustainable development

1    INTRODUCTION

Beijing is among the biggest cities with serious shortage of water, the amount of water resources per capita is less than 300 m³, 1/8 as much as per capita in China, and 1/30 in the world [4]. Water resources have become an important factor that conditions Beijing’s economic development. It is certain that Beijing will develop sustainablly in the 21^st century, but the scale and speed of the development should depend on sustainable utilization of water resources.

2    ECONOMIC DEVELOPMENT IN BEIJING CONDITIONED BY WATER RESOURCES

For the past half-century, water conservancy works in Beijing have controlled over 70% of mountainous area, more than 75% of runoff has exploited and utilized [4], and relatively integral system of flood control, water supply, water environment has been established, which strongly supported the social progress and economic development of the capital city. Water crisis, however, occurred many times during the progress, especially, in the five continuous low-flow years in the early of the 1980s, seriously influenced Beijing’s economic development. The development and utilization of water resources in Beijing underwent roughly the following three stages:

2.1    Rapidly economic development with early exploitation of water sources

Between 1949 and the middle of the 1960s, the exploitation and utilization of water resources in Beijing was in initial stage so that the water resources were relatively abundant and exploited them in time: Guanting and Miyun reservoirs were built successively, using as two big sources of Beijing water supply; Yongding river and Jingmi diversion channels were built as two arteries of Beijing water supply; the 3^rd, 4^th, 5^th, 7^th tap water plants using groundwater and the 6^th using surface water as sources were built one after another. Therefore, the development and utilization of water resources accelerated development of society and economy. Industry system of metallurgy, chemistry, electric power, textile and so on were established successively, the gross output value of industry amounted to RMB7.15 billion yuan ($ about 0.86 billion ), 40 times as much as the early of the new China foundation, water consumption of industry increased from 30 million m³ to 640 million m³ at the average rate of 26% each year. Moreover, agricultural irrigation area rapidly expanded from 14,000 hm² to 246,790 hm², and the population of the city was up to 3.75 million. Since the water supply there exceeded the demand for high-speed development, the supply and demand was basically in balance then.

2.2    Economic development sustained by excessive underground- water extraction

Heavy industry such as electric power, chemistry, iron and steel industry, of which water consumption is substantial, were built and extended suddenly in Beijing between 1965 and 1980. Gross industrial output value amounted to RMB20.93 billion yuan in 1980, three times as much as in 1965, and meanwhile, industrial water consumption increased to 1.3 billion m³, twice as much as in 1965. Moreover, agricultural irrigation area was expanded annually at the same time so that irrigation water reached 2.9 billion m³, over 60% of total city water consumption. Because of excessive growth of industrial and agricultural production, the contradiction of water supply and demand became increasingly acute and water crisis arose constantly. In order to obtain top economic effect, Guanting reservoir had to no longer supplied water for agriculture, only for the city and industry. Because the industrial region in west of Beijing was over concentrated, the water demand could see no way to be met. As a result, people in urban and rural areas had to extracted groundwater competitively, sank 36,134 wells within five years (1972—1977), the amount of annual extraction had reached more than 0.95 billion m³ that was 50% beyond groundwater recharge in the urban area by the end of the 1970s, and the accumulated deficit amounted to 1.7 billion m³, which caused groundwater continuously descending by 10～20 m, formed a funnel area of 1000 km², and led to sources depletion and vegetation regress there. Beijing’s development depended on excessive groundwater extraction and the sacrifice of the environment in that stage.

2.3    Striving for development by water saving

As Beijing’s economy has grown at a high-speed and city scale has extended unceasingly with proceeding of reformation and opening up since 1980s, the industrial and urban domestic water consumption has been rapidly increasing. However, the exploitable potential is limited, and sources of water supply for city and industry have to turn to original irrigation water. Miyun reservoir, for example, was built mainly for agricultural irrigation, which supplied 0.8～0.9 billion m³ per year for irrigation before 1980s, but reduced to 0.15 billion m³ per year in 1994. Because water shortage became a main factor conditioning Beijing economic growth, the State Council decided that Miyun reservoir would no longer supply water for Tianjing city and Hebei province so as to reduce temporarily water crisis in 1982. During the peak hours of the city water consumption in the middle of the 1980s, however, the amount of water shortage was still up to more than 500,000 m³ per day, forcing the plants that consume a large quantity of water quitted work, part units of power plant stopped operation, and domestic water of city supplied within a certain time so that the economic growth and social development were influenced seriously by the water shortage. Because the exploitable sources are very finite, people’s attention has to turn to water saving, by which per unit water can create more economic benefits. The rate of recycled industrial water increased from 58% in 1980 to 84.04 % in 1992, consequently, the amount of industry water collection that does not include recycled water reduced from1.35 billion m³ to 0.78 billion m³, but industrial output value grew 20.93 billion yuan to 59.97 billion yuan, whose average rate of annual growth was 9.2%. Since irrigation sources are less and less, water-saving-irrigation techniques such as canal lining, low-pressure pipeline, sprinkler and drip irrigation are used, instead of straggling irrigation manner, in order to raise the utilization rate of water. As a result, the grain yield per m³ of water consumption increased from 0.5 kg to 2.0 kg. The capital development has been sustained by water saving.

3    PRESENT-SITUATION ANALYSIS OF DEVELOPMENT AND UTILIZATION OF WATER RESOURCES

3.1    Development and utilization of water resources close to limit

Development and utilization of water resource has reached high level in Beijing. There 84 reservoirs, 329 sluice gates, 433 small reservoirs and 50 rubber dams, which control over 70% of mountainous area and the rate of water harvesting (p=50%) is up to 75% [4]. For one thing, the exploitation of water resources has approached to limit, Erdaohe reservoir and its division works, planned to build near future, is the only large-scale water conservancy project that will invest RMB1.53 billion yuan, the water supply, however, is only 100 million m³ [4]. For another, excessive extraction of groundwater is very serious. The exploitation in some areas has been beyond the limit of sustainable utilization, causing partially river drying up, groundwater depletion and water-environment aggravation. By 1994, excessive extraction of underground water had accumulated 4.2 billion m³, and the funnel zone in the urban area had extended to 2100 km², 1/8 of total city area. It is impossible to further extend the groundwater extraction, on the contrary, necessary to seek other sources to redress the one so as to rise back in the funnel zone. Consequently, the exploitation potential is very limited.

3.2    Inflow in both large-scale reservoirs annually decreasing

The amount of water supply of Miyun and Guanting reservoirs, both large-scale ones in Beijing, was 83% of total surface water supply all over the city in the 1980s [3]. With development and utilization of water resources in the upper outside Beijing, the inflow of the reservoirs sharply reduced from more than 3.0 billion m³ in the 1950s～1960s to 0.8 billion m³ in 1995, with a strongly decreasing tendency. Table 2-1 shows that the annually decreasing tendency of the inflow of Guanting reservoir.

3.3    Water-saving potential limited

Since the exploitation of water resources in Beijing has approached to limit, the cost of further exploiting sources is rather high. However, water-saving investment is even lower with better benefits, hence, substantial achievements have been made in Beijing up till now： The rate of recycled industrial water increased from 48.6% in the 1980s to 86.1% in 1995, only 50% in China in1993 and 75.3% in Japan in 1989, of which the rate of cooling water in Beijing was up to above 90%, therefore, water consumption per ten thousand industrial-output-value reduced from 357m³ to 65m³ in1995; irrigation area with water-saving facilities grew from less than 2,600 km² in 1980 to 260,000 hm² in 1999, 80% of total irrigation area, meantime, the grain yield per m³ of water consumption increased from 0.5 kg to 2.0 kg. With increasing development of water-saving engineering, the difficulty and cost are growing; therefore, it is impossible to obtain such benefits like before. Though there is still potential in industrial water saving by means of improving technology and equipments, reformation of technology and equipments simply for water saving is, after all, limited. It will take long time to renew the technology and equipments to save water. Moreover, irrigation area without water saving in Beijing is only 20% of total irrigation area, it is not, however, ignored that water-saving irrigation certainly reduces redressing groundwater. So water-saving potential is also limited.

3.4    Environmental water consumption increasing

Environmental quality is premise of sustainable utilization of water resources and sustainable growth of economy. Since the 1970s, Beijing’s water environment has paid a heavy price for its development so that many rivers dry up in most time, even becoming sewage ditch, and play a flood-discharge role only in high-water season in high-flow year, which not only threatens directly people’s health, but also contaminates water sources and further aggravates original shortage of water resources. Furthermore, dryly-sandy riverbed becomes sources of sand-dust storm in urban area. In future planning of the city, the certain amount of water used for green space as well as ecological environment must be considered so as to recover accommodation of rivers, extend urban lake surface, improve environment and climate, prompt environment appreciation, and maintain virtuous cycle of ecological environment. Environmental water consumption, therefore, will certainly increase.

3.5    Urban domestic water consumption rapidly increasing

Urban domestic consumption that uses for city living is dependent upon two factors, water rating per capita R and population P. The former deals with city character, scale, living level, facilities of water supply and so on. In a given city, if water rating per capita is R₀ and population is P₀ currently, urban domestic consumption in n years is

W_D(n)=R₀ (1+α)ⁿ P₀ (1+β) ⁿ

Where  W_D(n)—urban domestic consumption in n years

α—average annual growth rate of water rating per capita

β—average annual growth rate of population

when water rating per capita and population increase annually at the rate of αand βrespectively, the urban domestic consumption increases annually at the rate of (α+β+αβ). Beijing is the capital in China and international metropolis, so the public water consumption of municipal uses and business houses substantially increases with the city-scale expansion; domestic consumption increases with improvement of living level, perfection of water-supply facilities and popularity of domestic water heater; and the population grows also with the city-scale expansion. As a result, urban domestic water consumption has been increasing without tending to slowdown as shown in Fig. 2-1, which is the most sensitive to water crisis because of requiring concentrative water supply, high rate of guarantee and good water quality. However, domestic water consumption in China, in both urban and rural areas, is only 8% of total water consumption, which does not affect greatly the growth of total water consumption, so it is not taken seriously. In Beijing, however, the proportion of only urban domestic consumption, not including one in rural area, is considerable. The details can be seen in Table 2-2.

4    SUSTAINABLE DEVELOPMENT BASED ON SUSTAINABLE UTILIZATION OF WATER RESOURCES

Gross of water resources W_G is given to a region by nature, basically a constant, while bearing capacity of water resources W_B is ability that meets the demands for man to do social and economic activities under a certain social, economic and technical conditions in a certain stage of social development. Bearing capacity of water resources varies with social and economic development, not only conditioned by gross of water resources, but also affected by man’s manner of social and economic activities and water-use efficiency. In given water resources, the higher the development level of society, economy and technology is, the higher the bearing capacity of water resources is. Generally, bearing capacity of water resources has a marginal value W_Blim under a certain economic and technical condition in a given area, which is equivalent to the sum of maximum available water supply W_Amax and maximum recycled water W_{Rmax :}

W_Blim = W_Amax + W_Rmax

The condition of sustainable utilization of water resources is     

W_A ≥ W_C   or  W_A ≥ W_U －W_R

Where: W_A— available water supply

W_C — water collection that is consumed directly from surface-water collection and groundwater extraction, not including recycled water

W_U — gross water utilization that is gross used water, including recycled water

W_R — recycled water

Fig. 3-1 is a schematic diagram of available water supply and water consumption, which illustrates that excessive exploitation occurs when W_C>W_A  or  W_U>W_B。 Indeed, water resources are recycled or renewable, but sustainable utilization is impossible if the rate of exploitation and consumption is faster than that of regeneration. Based on the first balance result between water supply and demand in Beijing by 2010, analyzed by The Report of Planning Beijing Sustainable Utilization of Water Resources for the Early of the 21st Century [4], the water shortage will be up to 1.18 (p=50%), 1.65 (p=75%) and 2.00 (p=95%) billion m³ respectively, 0.42, 0.66 and 0.93 billion m³ respectively in the planning urban area. The details can be seen in Table 3-1. The water shortage is so much that it must restrict the economic development of the capital. However, it is impossible to take the former measures—simply tapping the potential of water resources—so as to adapt the water supply to the demand of the city economic development. Before the diversion project from south to north in China (i.e. water is diverted across different basins from Yangtze river to Beijing) comes true, Beijing has to continue development and water saving for raising the bearing capacity; and by the local bearing capacity of water, meanwhile, to restrict strategically its scale and speed of the development in the following three respects:

(1) Population

Man is a main body factor of sustainable development, but also brings about negative consequences of resources consumption, especially water resources consumption, and environment destruction at the same time. Population of Beijing, including nonnative and floating population, has amounted to over 15 million currently, increased by about 50% since the middle of the 1980s, which leads to great pressure to the water resources of original scarcity.

(2) Scale of the city

The sudden expansion in city construction that began in the early 1980s with opening up, and still continues nowadays, has enormously increased the need for water. The many new economic development zones have been established in each county and district in Beijing in the past years, of which more than twenty are under construction or have approved. Haidianshanhou in Haidian district and Fengtaihexi in Fengtai district, for example, both development zones near urban area, are under construction. Therefore, the new development zones must take the water resources as the most important constraint condition, developing economy and protecting environment in phase, and doing both water supply and sewage disposal at the same time; otherwise the hidden or delayed water crisis will occur.

(3) Speed of economic growth  

Speed of economic growth ought to correspond to increase rate of bearing capacity of water resources. Hence, it will certainly results in new man-made water crisis to overemphasize speed of economic development or to pursue simply economic benefits without consideration of the bearing capacity of water resources.

5    CONCLUSION

Water shortage in Beijing is a main factor restricting economic growth. The local bearing capacity of water resources must be taken as an important constraint condition planning Beijing future development—act according to actual circumstances, and the scale of the city development and speed of economic growth should be controlled strategically so as to implement sustainable development.

References

[1]  Liu Changming, He Xiwu. Water problem strategy for china’s 21^st century. China: Science Press, 1996.

[2]  Liu Changming, He Xiwu, Ren Hongzun. Research on water problems in china. China Meteorological Press, 1996.

[3]  Yan Changyuan. Beijing water conservancy. China: Science Popularization Press, 1997. 121-263.

[4]  Leader Group of sustainable utilization of water resources in Beijing for the early of the 21^st century. Report of planning Beijing sustainable utilization of water resources for the early of the 21st century. Beijing: 1999.

[5]  Beijing Institute of Water Conservancy Planning and Design. Utilization of water resources in Beijing. 1985.

Table 2-1  annually decreasing inflow of Guanting reservoir *

*Data: 1950—1989 from [3], 2000—2010 from [4]

Fig. 2-1    Urban domestic water consumption increasing annually****Data: 1949—1991 from [3], 2000—2010 from [4]        

Table 2-2  Water consumption of domestic, industry, agriculture and environment with their percentage of totalwaterconsumption*** billion m³

  ***Data: 1981 from [5], 1995—2010 from [4]

Fig. 3-1    Schematic diagram of available water supply and water consumption

Table 3-1  The first balance result between water supply and demand in Beijing by 2010 ****

billion m³

****Data from [4]