Shandong province is located in the warm temperate monsoon climate zone, with four distinct seasons, concentrated precipitation, large temperature difference and high frequency of drought and flood. The annual average fresh water resources in the province only account for 1.09% of the total water resources in China, and the per capita water resources are 344m3, which is only 14.7% of the national average water resources and 4.0% of the world average water resources. The average water resources per mu in the province is 307m3, which is only 16.7% of the national average water resources. This is an area that is seriously short of water.
I. Analysis of the causes of drought
1. The geographical distribution of water resources is unreasonable, with great interannual variation and uneven distribution within the year.
The regional distribution of water resources in Shandong is extremely uneven, and the average annual precipitation has decreased from 850mm in the southeast coast to 550mm in the northwest of Shandong. The interannual changes are drastic, with obvious high and low years and continuous high and low years. The maximum annual runoff is 12.8 times of the minimum annual runoff. The distribution is uneven during the year, and the precipitation in flood season accounts for 70% ~ 80% of the whole year.
2. The demand for water resources is increasing with economic and social development.
In 2000, the industrial water intake in Shandong Province was165438+700 million m3, 1994, 2.94 billion m3, 1995, 3.848 billion m3, 20 10, 4.363 billion m3 and 2000 ~ 200, respectively. The irrigated area of farmland increased from 247,700 hm2 in 1949 to 4,463,700 hm2, and the annual water consumption of agricultural irrigation increased from 400 million m3 to nearly 654.38+08 billion m3. The domestic water consumption of urban residents increased from160,000 m3/ year in the early days of the founding of New China to 930 million m3/ year (the annual average of 2000 ~ 2065.438+00).
3. Water pollution aggravates the contradiction between supply and demand
According to the water quality test data in 2002, * * * evaluated 66 rivers with a total length of 4389.4km, and none of the monitored rivers reached the first-class water standard, with the second-class water quality accounting for 6. 1%, the third-class water quality accounting for 7.6%, the fourth-class water quality accounting for 9. 1% and the fifth-class water quality accounting for 63%. * * * Evaluation of 30 reservoirs failed to meet the first-class water standard. Class II water quality accounts for 6.7%, Class III water quality accounts for 40%, Class IV water quality accounts for 33.3%, Class V water quality accounts for 10%, and inferior to Class V water quality accounts for 10%.
4. Serious waste of water resources
In terms of industrial production, in 2002, the water consumption per 10,000 US dollars of output value in Shandong Province was 2030m3, which was 5 14m3 in the United States and 208m3 in Japan, which was four times that in the United States. 10 times that of Japan. The reuse rate of industrial water is 65%, which is lower than the international level 10% ~ 20%. Agricultural irrigation methods are backward and consume a lot of water. Urban water supply pipe network and water appliances are outdated and backward, with serious leakage, and the loss rate accounts for 20% of water supply. The phenomenon of wasting water in public places such as institutions, schools, industrial and mining enterprises can be seen everywhere.
5. Human activities lead to the decrease of surface water reserves.
From 1950s to the end of 1970s, in order to obtain more grain, reservoirs and lakes were enclosed for farmland, barren hills and beaches were marched, rivers were shrunk for farmland, water storage area was reduced, and ecological environment deteriorated. Since the reform and opening up, cities
Urban construction and development zone construction occupy a large number of lakes and depressions, resulting in a decline in water storage capacity, which not only makes a large number of water resources lose, but also intensifies the occurrence of floods. For example, the depressions in Jinan North Park have all been occupied by urban areas, and the former scene of "lotus flowers on all sides and willows on three sides, a city with mountains and half a city with lakes" no longer exists. Qingsha Lake in Xiaoqing River Basin has been transformed into ten thousand mu of fertile land, and Yangsiwa flood storage and detention area is also facing the same fate.
6. Treat the flood as a beast, only seeing the harm of water and ignoring its benefits.
In the guiding ideology of water control, only pay attention to drainage, ignore regulation and storage stagnation, and have a single thinking. Once a rainstorm or flood happens, we always do everything possible to make it as safe as possible. Yi river, Shuhe and Nansi Lake basins are rich in water resources in Shandong Province. In the past, they only paid attention to drainage, ignoring the development and utilization of water resources, and a large number of flood resources were not fully utilized, which also aggravated the flood control pressure in brother provinces.
7. There are many ways to manage water resources, and the allocation cannot be optimized.
The water resources management system that divides urban and rural areas, surface water and groundwater artificially increases the difficulty of water resources management, and it is impossible to realize the joint dispatch and optimal allocation of various water sources. 1998 ~ 2002, Shandong Province suffered from drought for years, especially in Jiaodong Peninsula. The surface water reserves are almost exhausted, and the groundwater level has dropped significantly. The main sources of urban water supply in Yantai are groundwater in Dagujia River Basin and water storage in menlou reservoir. According to the principle of using surface water first and then groundwater, reservoir water is used first and then groundwater is used. However, because the urban water supply is managed by the urban construction department and the price of groundwater is lower than that of surface water, in fact, groundwater is used first, then reservoir water, and groundwater is used again. Menlou reservoir river basin has a large area and large inflow, which will be abandoned in most years. If water resources are managed in a unified way, the waste of water resources can be avoided.
Second, the shortage of water resources seriously affects economic and social development.
Drought ranks first among all kinds of natural disasters in Shandong Province. According to statistics, in the 42 years from 1949 to 1990, except for 1964, there were droughts in different degrees in 4 1 year, and the average area affected by disasters in the province every year.
1.7372 million hm2, and the affected area 1.0654 million hm2. Among them, 1989 has the largest drought-affected area of 4,225,300 hm2. Since 1990s, due to the decrease of rainfall, the Yellow River has been cut off and the drought has become increasingly serious.
During the period from 2003 199 1 to 13, the average annual disaster-affected area in the whole province was 236 16000 hm2, and the drought-affected areas in 1997, 200 1 and 2002 were all 3.5 million. Especially in 1999-2002, severe drought occurred for four consecutive years, resulting in reduced agricultural production, industrial and mining enterprises stopped production, and urban and rural water supply was critical. Drought disaster affects industry, agriculture, service industry and people's lives, and has a great impact on economic and social development.
In 200 1 year, the drought-affected area in the whole province was 3.533 million hm2, accounting for 53% of the sown area. Drought 1.33 million hm2, and the land that cannot be sown on time due to drought is 6.63 million hm2. Dry seedling crops are 65.438+467,000 hm2, and the population with dry seedling difficulties is 2.45 million. The water shortage in Yantai and Weihai is becoming more and more serious, and the gatehouse, Mi Shan and Gushan reservoirs that supply water to the two cities are basically exhausted. The drought in the first half of the year caused more than 200 enterprises to stop production or semi-stop production, and the economic loss was 1 10 billion yuan. The drought in the whole province caused industrial economic losses of 15 1 100 million yuan, grain losses of 40 1 10,000 t, and economic crops losses of 6.7 billion yuan.
In 2002, the drought-affected area in the whole province was 36 1.33 million hm2, of which 1. 1.73 million hm2 was severe drought, crops could not be sown for 23 1.00 million hm2 due to lack of water, 672,000 hm2 seedlings died and 7.92 million people had difficulty drinking water. More than 500 industrial enterprises in the province have restricted water, production or production. There are 60 cities above the county level with insufficient water supply, affecting 2.07 million people. Binzhou cotton mill with annual profit and tax of 65.438+0.4 billion yuan was forced to close due to lack of water. The Jining section of the Beijing-Hangzhou Canal was suspended for more than 654.38+100,000 days, and 2 million tons of coal could not be transported in time. When Nansi Lake dried up, the economic loss of Weishan County was as high as 654.38+0.33 billion yuan. The economic losses caused by drought in this province exceeded 26 billion yuan.
A large amount of groundwater is pumped out, which leads to a significant drop in groundwater level and the formation of a large funnel area. 1975, the area of underground water funnel in the whole province was less than 1000km2, and 1979 reached 283 1km2, reaching 1989.
65,438+690 km2, and the area of groundwater funnel area at the end of 2002 was 27,586 km2. During the period of 1980 ~ 1988, 3,778 mechanical wells were scrapped due to the decline of groundwater level; during the period of 1980 ~ 1985 * *, 2,537 deep well pumps and submersible pumps were replaced, and 3,486 new wells were built, with a total investment of 5 106. The deeper the well is drilled, the less the water output of a single well and the lower the benefit. The groundwater level has dropped sharply, causing a large area of seawater infection disaster. 1979 The infected area of seawater is only about lOkm2. According to the general survey, the infected area of seawater in Shandong Peninsula 19 counties (cities, districts) is 1006km2. Seawater infection leads to secondary salinization of cultivated land, resulting in reduced grain production and difficulty in drinking water in rural areas.
Serious over-exploitation of groundwater causes land subsidence, which endangers the safety of urban buildings, railways and dikes. In the 1980s, Qingdao pumped a large amount of groundwater on both sides of Dagu River, with the cumulative amount exceeding 100km.
There are more than 5200 cracks and collapses 150 in the levee, which makes the levee lose its water retaining function. The subsidence of railway subgrade in Tai 'an suburb is also caused by over-exploitation of groundwater.
Third, countermeasures
The shortage of water resources has become a bottleneck restricting the sustainable development of Shandong Province. The sustainable utilization of water resources is the key to alleviate the contradiction between supply and demand of water resources and to support and guarantee the sustainable development of economy and society.
Major strategic issues at hand. According to the present situation of water resources and the needs of economic and social development, the potential of water resources should be further tapped. The Yellow River is an important passenger water resource in Shandong Province, with an average annual inflow of nearly 40 billion m3. In recent ten years, due to the lack of precipitation in the Yellow River basin and the increase of upstream water transfer, the water volume in Huang Heren has been reduced to more than 22 billion m3, and the water of the Yellow River has been cut off for 226 days from 65438 to 0997, which is unreliable. The decrease of the inflow of the Yellow River is mainly caused by the flood and drought changes of the Yellow River. Since 2003, the inflow of the Yellow River has improved, and the inflow in 2003 was 25.585 billion cubic meters. From June to June, 2004, the incoming water 1, 231.900 million m3, and there is still much room for Shandong Province to utilize the Yellow River. We should also make a scientific analysis of drought disasters. The climatic characteristics of Shandong determine that drought disaster is inevitable, but it does not depend entirely on the amount of water resources. Uneven regional distribution, uneven time distribution and large interannual variation of precipitation are the main causes of drought. Therefore, to solve the problems of water shortage and drought, comprehensive measures must be taken according to local conditions.
1. Speed up the reinforcement of reservoirs and lakes, and store floods to the maximum extent.
There are 32 large reservoirs, 52 medium-sized reservoirs 152, and 4,965 small reservoirs, with a total storage capacity of 154 billion m3, of which Li Xing has a storage capacity of more than 8 billion m3. Most of these reservoirs were built in the fifties and sixties of last century, and the projects were inherently inadequate. In order to ensure the safety of flood control, a certain flood control storage capacity is reserved and the initial water level (called limited water level in flood season) is specified. This regulation has played an important role in ensuring the safety of reservoir flood control, but it has a certain impact on water storage and reduces the storage capacity. Since 1990s, some large and medium-sized reservoirs in Shandong Province have been strengthened, and the accuracy of meteorological forecast has been greatly improved. The automatic rainfall forecasting in the whole province has been basically popularized, which greatly improves the flood forecasting cycle and provides conditions for the reservoir to operate according to the design water level. After all large and medium-sized reservoirs are operated according to the design water level, the water storage capacity will increase by 654.38+0.4 billion m3. Therefore, in order to further speed up the reinforcement progress of large and medium-sized reservoirs, the reservoirs that have completed the reinforcement should be operated at the design water level as soon as possible to increase the water storage capacity.
2. Make full use of the Yellow River water
The Yellow River diversion in Shandong Province covers 1 1 68 counties in the city. There are 63 culvert gates for Yellow River Diversion, with a designed diversion capacity of 2423m3/s, a designed irrigation area of 232,800 hm2 and an actual irrigation area of 65,438+800,000 hm2. Eighty-eight plain reservoirs have been built to divert water from the Yellow River, with a total designed storage capacity of 780 million cubic meters and a storage capacity of more than 2 billion cubic meters. Northwest Shandong is the main grain producing area and commodity grain base in Shandong Province. Since 1980s, relying on the support of the Yellow River, the grain output has increased steadily, and the rapid economic development of Qingdao has made great contributions to the Yellow River diversion. In recent years, plain reservoirs along the Yellow River have been built one after another, and the Yellow River water supply has expanded from agriculture to cities, industries and residents. The urban and industrial water in Jinan, Liaocheng, Dezhou, Binzhou, Dongying, Zibo and Qingdao is mainly from the Yellow River. Binzhou, Dongying and other cities send the Yellow River water to villages in coastal counties, so that people who drink bitter salt water for a long time can also drink the Yellow River water. The first cut-off occurred in the Shandong section of the Yellow River 1972, and frequently occurred after the first complete cut-off in the Shandong section of the Yellow River198/kloc-0. In order to ensure the ecological needs of the Yellow River, the state has made an important decision to ensure a certain amount of water under any circumstances. The fact that the Yellow River is cut off and the amount of water in the sea is guaranteed reminds us that the Yellow River water is no longer inexhaustible and must be used scientifically.
3. Rational exploitation of groundwater
Due to the continuous drought in previous years, a large amount of groundwater was exploited, and the area of groundwater funnel in Shandong Province reached 27,000 km2. In 2003, Shandong Province entered a relatively abundant period, with an average precipitation of 925mm and groundwater recharge.
The volume is large, and the funnel area is reduced to 14000 km2. With abundant rainfall in 2004, the funnel area will be further reduced. Shandong province has a large groundwater reserve, strong storage capacity and guaranteed recharge, which is the most acceptable.
Shit, the best water source. According to the requirements of the Ministry of Water Resources, "protect groundwater in development and develop it in protection", rationally develop groundwater. In areas with great groundwater potential, it is necessary to further increase opening up.
Strength, keep the balance between mining and compensation, and moderately overexploit in special years; The groundwater funnel area should be limited to mining or supplemented first before mining; The exploitation of groundwater is prohibited in serious funnel areas and salt water intrusion areas.
4. Build a water transfer network and implement inter-basin water transfer.
The South-to-North Water Diversion Project, which is being implemented, connects Nansi Lake, Dongping Lake, Yellow River Diversion Project and Jiaodong Water Diversion Project, forming an east-west water transmission artery, connecting Yangtze River water, Yellow River water and local water, providing conditions for rational and optimal allocation of water resources. To realize inter-basin water dispatching, it is necessary to build a water transmission network in Shandong Province, connect major rivers and large-scale water storage projects in Shandong Province, and adjust the wet season and dry season to complement each other. On this basis, the optimal allocation of water resources is realized. According to the order of local water, Yellow River water and Yangtze River water, they are allocated and used in turn.
5. Scientifically dispatch flood to realize flood resource utilization.
The premise of realizing flood resource utilization is to retain the reserved flood, which requires water storage engineering facilities first and inter-basin water transfer engineering facilities second. We should make full use of modern science.
Scientific flood control by technical means. With the popularization of automatic rain monitoring and forecasting system, rainfall and flood are under our monitoring at any time, and small flow is used as far as possible according to the incoming water situation to extend the flood discharge time.
Increase the seepage of rivers and replenish groundwater sources. Where conditions permit, lakes, depressions and wetlands should be restored to provide water for habitat, which can not only reduce flood hazards, but also improve the ecological environment. Yi river, Shuhe and Nansi Lake basins are rich in rainfall and have great flood control pressure, especially the poor exit of Nansi Lake, which is the key and difficult point of flood control in Shandong Province. The implementation of the South-to-North Water Transfer Project makes it possible to recycle the flood in Nansi Lake. In 2003, Nansi Lake discharged more than 2 billion m3, and it still stores 2.7 billion m3. After the completion of the South-to-North Water Transfer Project, Nansi Lake and Dongping Lake will move to the central and eastern regions, which will greatly relieve the pressure on water resources in Shandong Province and flood control in Jiangsu Province. The floods in yi river and Shuhe River are also valuable flood resources in Shandong Province, so it is necessary to study the utilization scheme of flood resources as soon as possible.
6. Gradually stop open flow, leakage and storage.
There are many rivers in Shandong province, and more than 900 large and medium-sized sluices have been built in various rivers. In the past, due to the adverse effects of river water storage on flood control, secondary salinization was easy to occur, so it was necessary to build sluice gates.
The dispute affected the construction of the sluice. The appearance of rubber dam has fundamentally alleviated the influence of river sluice construction and water storage on flood control. Therefore, where conditions permit, we should vigorously advocate the construction of water storage projects in rivers, especially rubber dams. Blocking river estuaries and building underground reservoirs are new explorations to intercept river undercurrents and reduce water loss in recent years. The construction of underground reservoir has the advantages of less investment, no occupation of cultivated land, no need for immigration and small evaporation, but how to prevent groundwater pollution needs further study and observation. Huang Shuihe, Dagu River and Dagujia River in Shandong Province have all built underground reservoirs at their estuaries, and the groundwater level in the reservoir area has been greatly improved, which not only relieves the contradiction of water shortage, but also prevents seawater intrusion.
7. Raise the national awareness of water conservation and build a water-saving society.
Agriculture is a big water user, accounting for about 75% of the water, and it has the greatest water-saving potential. It is necessary to reduce water consumption by reducing the loss in the process of water transmission, strengthening water metering and popularizing advanced water-saving irrigation methods. It is necessary to vigorously publicize the significance of water saving through the media, enhance the awareness of water saving among the whole people, advocate the social morality of "saving water is glorious and wasting is shameful", popularize water-saving appliances, advocate multi-use of one water, and turn water saving into the conscious action of all citizens. At the same time, people's water use behavior can be restrained by adjusting water price and using economic leverage.
8. Implement water resources integration and unified management of surface water and groundwater.
Implementing water integration and unified management of water resources is the premise of optimal allocation of water resources. The unified management of water resources is conducive to the unified planning and comprehensive management of water resources, and to the integration of water resources development, utilization, allocation, conservation and protection. According to the principle of surface water first, then groundwater, give priority to the use of local water, make full use of the Yellow River water, rationally exploit groundwater, scientifically divert the Yangtze River water, and realize the rational development, scientific allocation, comprehensive saving, efficient utilization and effective protection of water resources.