At the end of the Warring States period, Qin had a solid national strength and attached importance to water conservancy. By the time China was unified, its productivity had developed greatly. Dujiangyan in Sichuan, Zheng Guoqu in Guanzhong (see Zhengbaiqu) and Lingqu, which connects the Yangtze River and the Pearl River, are known as the three outstanding water conservancy projects in the Qin Dynasty. The prosperity of the country led to the climax of water conservancy construction in Qin and Han Dynasties.

Emperor Wu of the Han Dynasty blocked the mouth with a scorpion, and Wang Jing of the Eastern Han Dynasty ruled the river, all of which were important events in history. Water diversion irrigation projects have also been built in Hexi Corridor in Gansu and Yellow River Hetao in Ningxia and Inner Mongolia.

Sui and Tang Dynasties

During the Sui, Tang and Northern Song Dynasties, water conservancy in China reached its peak. Social stability, economic prosperity, water conservancy construction throughout the country, the technical level has also improved. The Sui Dynasty invested huge manpower to build the Grand Canal connecting the Yangtze River and the Yellow River valley, which linked the vast areas of the country by water transport and had a far-reaching impact on political, economic and cultural development.

In the Tang Dynasty, in addition to vigorously maintaining the smooth flow of canals and ensuring the transportation of grain to the north, farmland water conservancy was also developed in the north and south, including more than 250 large projects such as Sanbai Canal in Guanzhong and Tashan Weir in Zhejiang. After the end of the Tang Dynasty, the north suffered from repeated wars, and a large number of people moved south, which made the farmland water conservancy in the south develop rapidly. Water conservancy laws and regulations and technical specifications have appeared, such as "Ministry of Water" in Tang Dynasty and "General Discussion on River Defense" in Song Dynasty.

Yuanming

From the Yuan and Ming Dynasties to the mid-Qing Dynasty, water conservancy in China experienced another 600 years of development. Beijing was the capital of Yuan Dynasty, and the Beijing-Hangzhou Canal was opened. Since the Yellow River was diverted from Huai River in the Southern Song Dynasty, there have been frequent river disasters. In the Ming Dynasty, the Yellow River was vigorously controlled, and the Yellow River was fixed and the Gaojiayan was built to form the hongzehu reservoir, so as to ensure water transportation.

These measures played a great role in social stability and economic development in the Ming and Qing Dynasties, but they also left serious problems for the Huaihe River system. In the middle reaches of the Yangtze River, the Jingjiang levee was strengthened and the embankment of Dongting Lake was developed, which promoted the agricultural production in the two lakes. Water conservancy construction in the Pearl River Basin and the southeast coast has also made great progress. However, on the whole, the development of water conservancy in China has been slow since the second half of the 6th century.

Ching Dynasty

During the late Qing Dynasty and the Republic of China, domestic troubles and foreign invasion were frequent, and the country was unable to build water conservancy projects, resulting in the disrepair of rivers, the shrinking of irrigation areas, the interruption of the Beijing-Hangzhou Canal and the decline of water conservancy. However, with the gradual opening of the sea ban, some western science and technology were introduced into China, and water conservancy institutions such as Hehai Engineering College were established to train water conservancy technical personnel.

During this period, some projects were also built, such as Shilongba Hydropower Station in Yunnan in 19 12, Lubao Sluice in the Pearl River in the 1920s, Qujiadian Sluice in Yongding River in the 1930s, canal lock in northern Jiangsu and Guanzhong Bahui Irrigation Project in Shaanxi. However, floods and droughts are becoming more and more serious all over the country, and it has become an urgent demand of the broad masses of people to regulate rivers and build water conservancy projects.

Extended data:

"Governing the country must first control the water". After the founding of New China, the Party and the government put water conservancy construction in an important position to restore and develop the national economy. President Mao Zedong has called for "the Huaihe River must be repaired", "the Yellow River must be handled well" and "the Haihe River must be eradicated", and waves of water conservancy construction upsurge have been set off in China.

The Fifth Plenary Session of the 14th CPC Central Committee adopted the Proposal of the Central Committee on Formulating the Ninth Five-Year Plan for National Economic and Social Development and the Long-term Target of 20 10, which put water conservancy at the top of the national economic infrastructure, marking that China's water conservancy development has entered a new stage, the dam fortification standards have been greatly improved, and the gradually improved flood control, flood fighting and disaster reduction system has become a solid barrier for economic and social development.

Baidu encyclopedia-water conservancy