Linyi City, located at the junction of Sulu and Shandong, is a key watershed area of "Three Rivers and Three Lakes" in China, one of the key cities for water pollution prevention and control in Huaihe River Basin, and also an important catchment area for the East Route Project of South-to-North Water Transfer. It is of great responsibility and far-reaching significance to maintain the ecological environment security of the river basin. The high-standard water quality requirements, unique geographical location and rapid development of industrial economy of South-to-North Water Transfer Project put forward newer, higher and stricter requirements for water pollution prevention and control in Linyi City.
To this end, our city has overcome many difficulties such as lack of financial resources and vigorously implemented the "Clear Water Project". In accordance with the guiding principles of "grasping point sources to protect the river basin, grasping point sources to promote the river basin, and comprehensively grasping key points", the guiding ideology of "backward governance, advanced protection, seeking truth from facts, adapting measures to local conditions" and "pollution control to promote development, seek benefits and ensure stability" has been determined, and the Tenth Five-Year Plan for Water Pollution Prevention in Huaihe River Basin, the East Route Project of South-to-North Water Transfer and the Pollution Control Plan of Shandong Province have been strictly implemented. While deepening the adjustment of industrial structure, we focused on strengthening the protection of centralized drinking water sources, the discharge of industrial pollution sources up to standard, the treatment of urban domestic sewage and the ecological protection of river basins, and achieved remarkable results.
First, the water system and water resources in Linyi City
(a) the basic situation of the water system. Linyi is located in the upper reaches of Huaihe River Basin. Taking Yimeng Mountain as the center, a radial water system is formed, which is dominated by yi river water system, Shuhe water system and Zhong Canal water system. Most rivers are seasonal flash floods, especially the Yi and Shu rivers. The upper mountainous area has deep cutting, steep slope and curved river, which has the characteristics of high flood peak and large flow.
-the Yi River system. Yi River is the largest mountain torrent passage in this city, running through the city from north to south, with a drainage area of 9383 square kilometers. Yi river originated in the southern foot of Lushan Mountain in the west of Yiyuan County, Zibo, and entered from the northwest of Yishui County. It flows through Yishui, Yinan, Country-specific ones, Luo Zhuang and Tancheng to Jiangsu, and enters Lake Rome. In order to meet the needs of flood diversion, diversion canal and pigang flood diversion canal are excavated near Liujiadaokou downstream, and the flood of Yi River is divided into Shuhe River and Zhong Canal in flood season. The first-class tributaries of Yihe River are Dongwenhe, Menghe and Beng River, which flow through Mengyin, Yinan, Pingyi, Feixian and Lanshan counties respectively.
-Shuhe River system. Shuhe River, located in the east of our city, is the second largest river in our city. The city's drainage area is 3936 square kilometers. Shuhe River originates from the southern foot of Yishan in Dongyugou Township, Yishui County, and flows through six counties and districts of Yishui, Juxian (Rizhao City), Junan, Hedong, Linshu and Tancheng from north to south. Daguanzhuang in Linshu County is divided into two rivers, with Laoshu River in the south, which flows into Jiangsu through Tancheng and then into Xinyi River. The east flow is Xinshu River, which flows into the Yellow Sea after entering the Liang Shi River Reservoir in Jiangsu.
-In the mid-1990s, papermaking and wine-making were one of the main industries in Linyi's industrial economy. Every county has wheat straw pulping and papermaking enterprises, and brewing enterprises used to be the backbone enterprises in counties. Paper-making wastewater, wine-making wastewater, a large number of small waste plastics, small starch and other pollution projects, as well as the increase of urban domestic wastewater, have seriously polluted river water quality. The results of water quality monitoring at the end of the ninth five-year plan show that the water quality compliance rate of key control sections in Yishu River Basin once reached below 20%.
After the prevention and control of water pollution in Huaihe River basin was started from 65438 to 0996, our city adopted a series of measures and invested a lot of money in environmental pollution control, which achieved remarkable results. The water quality of Yishu River was once clear in a short time. However, the low level of governance and enterprise standards have not fundamentally solved the pollution problem, and alleviating outbound water pollution depends to a great extent on natural conditions such as rainfall and river basin water volume. In 2000-2002, Liang Shi River Reservoir Pollution Incident, Rome Lake Water Pollution Incident and Xuzhou Water Source Canal Pollution Incident occurred successively, which attracted great attention of Su Ru Province and even the State Environmental Protection Administration, and the prevention and control of water pollution in Linyi City became one of the focuses of national attention.
-Yi R.
Yi River is the most important backbone river in Linyi City, with a total length of 287.5 kilometers. It has many functions such as drinking water source, industry, agriculture, agricultural irrigation and flood discharge, and plays a very important role in urban industrial and agricultural water use and people's life.
Yi river accepted industrial wastewater and domestic sewage from eight counties, including Yiyuan County, Zibo City. The water quality of the exit section before the creation mode was once surface water V, which was quite different from the water quality required by the tenth five-year plan of Huaihe River.