(1. Beijing Public Health Drinking Water Research Institute; 2. China Water Conservancy Society)
Water is the foundation of all things in the world, and the city is the concentration of human civilization, and it is also the residence where human beings who create civilization can live. Due to the shortage and pollution of water and the development of urbanization, the relationship between water and cities has never been so valued as it is today.
First, the birth and development of cities.
Throughout the ages, from home to abroad, human beings have lived by water, and many cities were born naturally because of water. In the process of city birth, water directly affects the style and layout of the city. The role of water in the city is all-round and consistent.
In ancient China, the communication between cities and towns was developed and expanded to a great extent through inland navigation, especially the Grand Canal connecting the whole country, which cultivated a large number of famous cities and towns. During the Sui and Tang Dynasties, the Sui and Tang Grand Canal, which runs through the east and west, gave birth to a number of famous ancient capitals such as Chang 'an, Luoyang and Bianliang. After the Yuan Dynasty, the Beijing-Hangzhou Grand Canal, which runs through the north and south, became more prosperous because of its connection with big cities such as Hangzhou, Nanjing and Beijing. At the same time, a large number of small and medium-sized cities such as Yangzhou, Huai 'an, Xuzhou, Jining, Liaocheng, Linqing, Dezhou and Cangzhou have been formed along the canal. It can be said that if there was no water and no water transportation at that time, it is hard to imagine how the city would develop and prosper.
The four ancient civilizations in the world are closely related to water. The ancient Egyptian civilization was born in the Nile, the ancient Indian civilization in the Ganges, the ancient Babylonian civilization in the banks of the Tigris and Euphrates rivers, and the Yellow River civilization became the mother river of Chinese civilization. Modern cities are mostly built and developed on the basis of ancient towns. Many large cities and economically developed areas at home and abroad are mostly located near major rivers, such as the Pearl River Delta and cities along the Yangtze River in China, the Rhine Economic Belt in Europe and the Mississippi River in the United States. The development of the city is inseparable from water, and the development of the city also promotes the development of aquaculture and water culture. However, the rapid development and expansion of cities have also brought water problems to cities: water shortage and water pollution.
Water makes the city full of vitality, and water shortage makes the city decline. Zhuxian Town, Kaifeng, Henan Province, one of the four famous towns in ancient China, was an amphibious hub in the canal transit area in the Northern Song Dynasty, and its unique geographical location made it an amphibious dock. Later, the canal was blocked for years, the water transportation was not smooth, commerce declined, and the city lost its vitality and became a little-known desolate town. The other three towns, namely Jingdezhen in Jiangxi, Foshan in Guangdong and Hankou in Hubei, are still famous for the vitality of water.
The development and prosperity of modern cities also benefit from the development of water and its culture. "There is heaven above and Suzhou and Hangzhou below". Hangzhou is famous in the world because of its beautiful and clean West Lake. In contrast, the East Lake in Wuhan, besides being the largest lake in China and the first batch of top 4A scenic spots in China, doesn't seem to make people think much, leading to the evaluation of "the East Lake is the largest and the West Lake is the name". In addition to the poor cultural background compared with the West Lake, the deterioration of water quality, the once occupied lake and the loss of resources are also one of the reasons that plague the development of East Lake.
"Water can carry a boat, but it can also overturn it". Dujiangyan City is famous for the Dujiangyan project built by Li Bing and his son more than 2000 years ago. From this point of view, the rise and fall of a city is closely related to water. Only a healthy water system, scientific allocation and rational use of water, the perfect combination of water and the city, can the city develop. Throughout history, no matter in foreign countries or China, water-rich areas have always been the most prosperous places in population and economy, and the famous Venice Water City is a typical example. On the contrary, the population and economic strength of areas lacking water resources are obviously inferior to the former.
Second, China urban water problems
In the long history of Chinese civilization, water control has always been a major event for rejuvenating the country and safeguarding the country. Since the founding of New China, especially since the reform and opening-up, in view of the grim situation of China's rapid economic and social development and the increasingly prominent contradiction between resources and environment, the CPC Central Committee and the State Council have placed the solution of water resources problems in an important position and adopted a series of major policies and measures. Over the past 30 years of reform and opening up, China's economy has maintained a high annual growth rate of nearly 10%, while the total water consumption has increased slightly, especially in the past 10 years, some areas have achieved zero growth or even negative growth; The per capita comprehensive water consumption, which accounts for 60% of the world average, ensures the rapid growth of the national economy three times the average growth rate of the world economy. Since the implementation of the Eleventh Five-Year Plan, the water consumption per 10,000 yuan of industrial added value has decreased by 30%, and the water consumption per 10,000 yuan of GDP has decreased by 20%. Both energy-saving and emission reduction targets have been achieved year by year.
However, the large population and small land, uneven distribution of water resources in time and space and mismatch with the layout of productive forces are not only the outstanding water situation in China at this stage, but also the basic national conditions that China will face for a long time. The situation of water environmental protection is still very grim, facing many difficulties and challenges.
In cities, due to high population density, rapid economic development and expanding scale, coupled with frequent droughts and floods and water pollution accidents, urban water problems are more prominent.
Shortage of water resources
Water shortage is a common problem in China, and it is getting worse. There are about 655 cities in China, and nearly two-thirds of them are short of water to varying degrees, among which 1 10 is seriously short of water. The famous South-to-North Water Transfer Project was built to solve the water shortage in the northern region, which can solve the serious water shortage situation in big cities such as Beijing and Tianjin.
In fact, urban water diversion has long existed, such as the earliest "Luanhe River to Tianjin" project. The shortage of water resources restricts the construction and development of Tianjin and affects the normal life of citizens. In order to solve the problem of urban water use, the State Council decided in September to build the Luanhe River Diversion Project, 198 1, to transfer water from Luanhe River to more than 300 kilometers across the basin. 1963, Hong Kong suffered a severe drought. In order to solve the problem of water shortage in Hongkong, China Municipal Government allocated special funds to build Shen Dong Water Supply Project, which was completed and put into operation on March 1965. Subsequent water transfer projects include "Luanhe River into the Tang Dynasty (Tangshan)", "Bilian River into Dalian", "Yellow River into Qingdao" and "Yellow River into Shanxi (Taiyuan, Datong, Shanxi, etc.). ), "River to Taihu Lake" and "Northeast-North-South Water Diversion" (part of the Songhua River Basin is transferred to Liaohe River to supplement.
There is also a city that lacks water quality. Hefei, for example, is a typical water-deficient city. Although Chaohu Lake is rich in water, its water body is seriously eutrophic, especially the water quality in the western half of the lake is Grade V or worse than Grade V for most of the year. In 2003, Hefei stopped taking water from Chaohu Lake and had to transfer water from Xianghongdian and Foziling reservoirs in the upper reaches. It can be seen that water pollution and water saving are not paid enough attention, and as a result, there is no water to drink at the water's edge, so we have to go far and near to get water to drink. Similarly, Dianchi Lake in Yunnan has to divert water from central Yunnan due to water pollution, and diverting water from other basins has become the most fundamental measure to save Dianchi Lake.
(2) Water pollution
At present, nearly 654.38 billion urban population in China is affected by unsafe water quantity and quality, and the task of ensuring the safety of urban drinking water and sudden water pollution incidents is very arduous. In 2009, 397 centralized drinking water sources were monitored in national key cities, including 244 surface water sources and 53 underground water sources/kloc-0. The monitoring results show that the water exceeding the standard is 5.88 billion tons, accounting for 27%.
Urban water environment pollution is serious, water pollution accidents occur frequently, and some pollution has caused bad effects. For example, in June, 2005, 5438+065438+ 10, an explosion accident occurred in Shuangbenzene Plant of China Petroleum Jilin Petrochemical Company, which caused a large number of benzene pollutants to enter the Songhua River, causing a major water pollution incident, resulting in a water cut in Harbin for four days. In May, 2007, cyanobacteria broke out in Taihu Lake, which led to a sudden change in the tap water quality of a large number of citizens in Wuxi city, which made it impossible to drink normally, leading to an unprecedented water crisis in Wuxi, and the urban area was cut off for several days. It can be seen that water pollution has become an important bottleneck for the rapid development of China's national economy. If the problem of water pollution is not well solved, the development of national economy will be seriously restricted.
The main water problems faced by cities can be summarized as follows: most urban rivers are cut off, sewage discharge increases, river water quality deteriorates, and algae blooms frequently; The cross-section of the river is reduced, all kinds of garbage are piled up along the coast, the river is seriously blocked, the drainage function is reduced, and the flowing water becomes stagnant water; River regulation is too hard and artificial, and the ecological landscape layout is poor; The urban water surface is insufficient and the water area is invaded.
Three. Water and urban planning and development
Over the past 30 years of reform and opening up, China's urbanization level has increased from 1978 to 17.90%, and reached 45.68% in 2008. From 1978 to 2007, the total number of cities in China increased from 2 16 to 655, which more than tripled. The urbanization rate of population increased from 17.92% to 44.94%, and the urban population reached 607 million, showing a rapid development trend. Cities of all levels and types have developed in an all-round way. Among them, the number of small cities with less than 200,000 people increased from 1 16 at the beginning of the reform and opening up to 286, an increase of nearly 1.5 times, and the population of small cities increased from 135438+00000 to 37605438+00000. The population increased by 2.8 times from18.768 million to 74 10 1000, an increase of 2.9 times; The number of cities with a population of 500,000 to 6,543.8+million has increased from 27 to 82, more than three times, and the population has increased from 6,543.8+099.47 million to 56010.5 million, an increase of 6,543.8+0.8 times; The number of megacities with 1 10,000 population increased from 13 to 58, an increase of 3.5 times, and the urban population increased from 29.883 million to 14830 1 10,000, an increase of 3.9 times, making it the fastest growing city.
With the acceleration of urbanization, the shortage of urban water resources and the harm of water pollution to the environment and ecology, as well as the shortage of water quality, are becoming more and more serious, which puts forward higher and more urgent requirements for the utilization of urban water resources and the protection of water environment. The expansion of urban scale and the improvement of urban functions put forward higher requirements for water quantity, water quality, water environment, water ecology, water safety, water landscape and water culture. This is a new major challenge for the departments involved in water management.
To this end, the water conservancy department proposes that economic and social development, water resources conservation, water environment management and water ecological protection should be considered as a whole, the strictest water resources management system should be implemented, and economic and social development should be coordinated with water resources carrying capacity and water environment carrying capacity to achieve sustainable economic and social development. The Ministry of Environmental Protection proposes to combine environmental protection with promoting the transformation of development mode, combine pollution reduction with promoting the strategic adjustment of economic structure, environmental governance and ensuring the improvement of people's livelihood, focus on solving outstanding environmental problems that endanger people's health and affect sustainable development, and give full play to the comprehensive role of environmental protection in optimizing economic growth.
However, at present, China's urban planning is still dominated and compiled by the competent construction department, and the overall urban planning is not coordinated with water resources planning and environmental protection planning. No matter how the city develops, water will always come first. The survival and development of human beings can not be separated from the water resources, and the survival and development of cities can not be separated from the water. Urban landscaping needs excellent water environment.
(a) urban planning should be based on water, depending on the amount of water.
Most cities are developed by good water sources. Cities are areas with the most concentrated water users, the largest water intensity, the highest water supply guarantee rate and water quality requirements, and the most prominent contradiction between supply and demand of water resources. However, in urban planning and construction, we seldom consider the carrying capacity of resources and fail to measure and measure the development of water. Therefore, urban planning should be based on water, that is to say, the scale and development of a city must be determined by water. At the same time, water conservation and water resources reuse must be considered in the planning. On the one hand, the city is crying for lack of water, on the other hand, there are many phenomena of wasting water in the city.
Because the bearing capacity of water resources is not considered in urban planning and construction, the over-exploitation of water resources in North China has exceeded 654.38+000 billion cubic meters, which is equivalent to the water volume of two Yellow Rivers, forming the largest groundwater funnel area in the world. Due to the over-exploitation of groundwater, about 60 cities and regions in China have formed groundwater funnels of different sizes. From Shanghai in the east to Urumqi in the west, from Harbin in the north to Haikou in the south, almost all large and medium-sized cities have groundwater table decline due to over-exploitation of groundwater, especially in cities with soft alluvium in plains, basins and river valleys. For example, Suzhou has accumulated more than 60 meters of subsidence in the past 50 years, and the subsidence area covers almost the whole city of Suzhou.
Urban planning should take water resources carrying capacity as one of the guiding ideology, reform and improve urban planning procedures, and strengthen the coordination between urban planning and water resources planning and management. Urban planning should fully consider the unified management of urban water resources and possible measures, and reflect them in a certain form as a necessary content. In the past work, the comprehensive water resources planning has a weak constraint on the overall urban planning, while the comprehensive water resources planning based on the overall urban planning emphasizes its service, which is often a "demand-oriented" planning, and the subjectivity of urban development greatly affects the rationality of water resources allocation. Therefore, the overall urban planning should be based on water resources. Urban master planning is the dominant planning that determines urban development, and comprehensive planning of water resources is an important basis for determining urban development. The Urban and Rural Planning Law of People's Republic of China (PRC) stipulates that "the formulation and implementation of urban and rural planning should follow the principles of overall planning, rational layout, land conservation, intensive development and planning before construction, improve the ecological environment, promote the conservation and comprehensive utilization of resources and energy, protect natural resources such as cultivated land and historical and cultural heritage, maintain local characteristics, national characteristics and traditional features, and prevent pollution and other public hazards, which is in line with the needs of regional population development, national defense construction and national defense. The Water Law of People's Republic of China (PRC) stipulates that "comprehensive river basin planning, regional comprehensive planning and professional planning closely related to land use should be coordinated with national economic and social development planning, overall land use planning, overall urban planning and environmental protection planning, taking into account the needs of various regions and industries".
For example, "Beijing Urban Master Plan (2004 ~ 2020)" particularly emphasized the constraints of ecological environment carrying capacity and water resources conditions on urban development at the initial stage of planning. When demonstrating the suitable population size of Beijing, the population size under the condition of water resources carrying capacity is considered emphatically. The Study on the Carrying Capacity of Water Resources and the Construction of Suitable Production and Life Style in Beijing, completed by the water affairs department, provides a quantitative basis for determining the total scale of population control in Beijing in 2020. At the same time, a chapter on "Conservation, Protection and Utilization of Resources and Energy" has been added to the plan, as well as the goal of building a water-saving society and the principle of giving priority to water quantity, total control and overall allocation in urban construction, especially the principle of strengthening the allocation of water resources in key development areas.
(b) Urban planning should be based on water, quantity and quality.
Stable water supply and its quantity are the basis of urban planning, and a good water environment is the image of the city, a symbol of urban civilization, representing the taste of the city and embodying its characteristics. Water environment is the basis of improving human settlements. As a water town city, the daily life of the general public is closely related to water, and living by pillow river and choosing water is the first choice for water town citizens. Therefore, the urban water environment development planning is also an important part of the overall urban development planning and an important aspect of the urban human settlement environment planning.
Water environment planning and construction should strive to create urban characteristics, create new highlights and show urban personality. It should be ecological and hydrophilic. There is no clear water in the mountains, no water in the city and no beautiful scenery. Humans are naturally hydrophilic. With the development of economy and society, the living standard of ordinary people has been greatly improved, and there are higher requirements for living environment and quality of life. People yearn for nature. Improving urban water ecological environment and fully embodying the landscape function of urban water environment is a very important aspect of improving citizens' living environment and quality of life, and also an important symbol of urban civilization. Therefore, fully embodying ecology and hydrophilicity has become the focus of modern urban water environment construction.
Water environment construction must integrate multiple functions. The essence of urban water environment determines its versatility. Urban water environment construction should maximize the overall planning of urban water conservancy, urban construction facilities, environmental protection, cultural layout and tourism development. It not only has the functions of flood control, water storage, environmental protection and urban construction, but also should be endowed with the functions of landscape, culture and improving urban taste.
The scale and layout of a city should conform to the natural carrying capacity of local water and soil resources, environmental capacity and geological structure, and adapt to local economic development, employment space, infrastructure and public service supply capacity; Environmental protection should adhere to prevention first and comprehensive treatment, strengthen the prevention and control of source pollution, and resolutely change the situation of pollution first and then treatment, and pollution while treatment. In recent years, because the environmental protection planning of many cities has not been implemented simultaneously with urban planning and urban construction, or in the overall planning of many cities, the discussion on environmental protection often only stays on the description of the treatment of various pollution points, resulting in the destruction of the urban environment to a certain extent and the increasingly serious environmental pollution, leading to the failure of urban environmental construction to enter the track of benign development. Therefore, with the implementation of urbanization strategy and the promotion of building a well-off society in an all-round way, people's requirements for human settlements are increasing day by day, and environmental protection in urban planning, especially water environmental protection, has been paid more and more attention by governments at all levels.
Anqing City, Anhui Province focuses on the "five modernizations" of water environment construction, that is, culture, lighting, beautification, purification and greening. Its experience and practice are worth learning and using for reference by related cities. Wuhan is known as the "city of 100 lakes" and is rich in water resources, which can be called "born of water, prospered by water and proud of water". They regard water resources as a core factor related to people's lives and the sustainable development of cities. Starting from the strategic height of ensuring the rational use of water and the sustainable use of water resources in cities, they have vigorously promoted water conservation, water environmental protection and waterfront landscape construction. In March 2009, it was named "National Water-saving City". The Hankou River Beach in Wuhan can effectively prevent floods in flood season by strengthening flood control works and building waterfront landscape, and provide a good place for citizens to relax and entertain on weekdays. This place, which used to be messy and often hit by floods, has now become the most beautiful scenery in Wuhan. Since 2002, the idea of connecting six lakes has been put forward, which has integrated the water landscape with the city and improved the quality and landscape of the city. From 1973 to 1995, it took Guilin more than 20 years to focus on pollution control. 1996 to 2005, focusing on ecological restoration of urban lakes; From 2006 to now, comprehensive ecological restoration construction has begun. At present, the ecological restoration of urban lakes and rivers in Guilin is interconnected. In the future, Guilin will be "a thousand peaks surround the wild and three rivers embrace the city." In the planning of Taizhou water system, the regulation of Fenghuang River is the epitome of Taizhou water culture and water landscape management. Through comprehensive improvement, Fenghuang River not only restored a natural ecological river in the past, but also fully demonstrated that it is a humanistic river.
In a word, there are still many urban hydrophilic landscapes in China, which have positive and far-reaching historical significance for excavating the connotation of urban culture and water culture, improving the overall taste of the city, adjusting the development layout of tourism and shaping the image of an international metropolis. Large, medium and small cities should combine their own scale, natural conditions, economic capacity and technical level, adjust measures to local conditions and do what they can; Give full play to the wisdom of workers in water conservancy, art, architecture and other industries, and carefully design and construct urban water conservancy projects, so that they can reach the heritage of existing water culture without endangering the safety of cities and people's lives and property.
(3) Urban planning should involve and coordinate water-related departments.
Water is the blood of the city, the basic demand of people's life, the basic guarantee of urban economic development and the spirit of the city. For cities, water is not only the basic condition for production and life, but also an indispensable and precious resource for ecological construction, economic construction, cultural construction and social construction. Making full use of precious water resources is an inevitable choice to improve the city's taste, charm, economy and life.
To realize the harmonious development between people and water, a water-friendly city and a waterfront city need the cooperation, communication and coordination of all departments. Water resources should be managed in a unified way, the quality and quantity should be coordinated, and the allocation of water resources should be gradual. In this regard, the practice of Heilongjiang Province is worth learning from all countries in the world.
In 2009, Heilongjiang province comprehensively promoted the planning and construction of waterfront cities, prospering the city because of water and enriching the people because of the city. Harbin first put forward "setting the city by water" in domestic urban planning and construction. Put forward four requirements for the planning and construction of waterfront cities, namely:
First, we should do a good job in water resources planning of waterfront cities. Establish ecological concept and pay attention to environmental protection; Establish cultural ideas and protect the historical and cultural heritage of the city; Establish functional concepts, strengthen infrastructure construction, and meet various needs of the city; Establish a fashion concept, pay attention to characteristics in style, reflect the atmosphere, aura and exquisiteness; Establish economic concept and promote urban economic development and industrial structure adjustment.
Second, we must do a good job in water resources protection in waterfront cities. It is necessary to combine the planning and construction of urban waterfront with the implementation of national key river pollution control projects and key livelihood projects such as "three supplies and two treatments" in Heilongjiang Province, and accelerate the construction of urban sewage and garbage treatment projects in waterfront areas. It is necessary to combine the construction of flood control dike with the construction of waterfront city landscape to ensure the safety of dike.
Third, do a good job in water resources development of waterfront cities. We should pay attention to the comprehensive utilization of culture, leisure, commerce, tourism and other functions; It is necessary to vigorously promote the tourism development of waterfront cities and accelerate the construction of waterfront tourist areas such as Wudalianchi, Jingbo Lake and Xingkai Lake.
Fourth, we should do a good job in water resources management in waterfront cities. Strengthen the publicity and implementation of the national urban and rural planning law and the supervision and inspection of law enforcement, straighten out the management system and make good use of water resources.
In short, we should fully realize that cities cannot "grow bigger". In urban construction, we should follow the trend, be greedy for perfection, and engage in "image project" at the expense of both human and financial resources. Urban development must be moderate, and efforts should be made to achieve the balance between urban construction and natural environment. Consciously realize that water transfer is not a panacea, it is only a way to solve the problems of water pollution and water shortage. The development of any city will be restricted by resources and environment to some extent. We must find the third way to solve the water problem, develop water-saving economy and build a water-saving society. City by water, city by water. We must set up the goal of "supporting the sustainable development of economy and society with the sustainable utilization of water resources" and pursue the concept of harmonious development of people and water. To realize the harmonious development of city and water, we must adhere to the principles of coordinated development of economy, society, environment and ecology, intergenerational principle of resource utilization and coordinated development among regions; Overall consideration should be given to the water quality and quantity guarantee of water resources, the macro-control of total water resources and the micro-management of water quota, the safety of urban water supply system and ecosystem, the development demand of urban scale and the constraints of water resources carrying capacity.
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