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November 12th, 2019
Via Future Directions International, a report on another drought in China:
Water is described as China’s Achilles heel. It is ‘the most long-term and fundamental of China’s vulnerabilities … China has failed to secure a sufficient amount and quality of water for its citizens, leading to an “absolute scarcity” of the resource’. The drier than normal conditions in the south of the country, in the middle and lower reaches of the Yangtze River, have brought that vulnerability into focus.
Some parts of the region are reportedly experiencing the worst drought in 50 years. Anhui province, in south-eastern China, is one of the worst-affected regions and received 60 per cent less rainfall than normal between August and October. The neighbouring provinces of Hubei, Jiangsu, Jiangxi and Zhejiang have also been affected. The regional dry season usually runs from October to May; this year, however, water levels have dropped earlier than usual. Officials from the meteorological administration blamed lower rainfall, higher temperatures and climate change for those conditions.
Comment
Southern China is generally wetter than the north and four-fifths of the country’s water is located in southern provinces. That imbalance led water planners and engineers to devise a scheme to transfer water from the south to the north via diversion canals. The first of three canals built as part of the South-North Water Diversion Project (SNWD) become operational in 2013. If the SNWD is ever completed, it will be capable of diverting 45,000 gigalitres of water annually from the Yangtze to the Yellow River each year.
The central and eastern canals have both been operational since 2014, but further refinements are still being made. In October 2019, a new channel was opened to increase the water supplied to Beijing by almost 50 per cent. Zhong Zhiyu, a chief engineer and delegate to the March 2019 Chinese People’s Political Consultative Conference, warned that Beijing has become over-reliant on water from the south. He also suggested that the water level in the Danjiangkou Reservoir, which supplies water to Beijing as part of the SNWD, could be lower this year.
Beijing sources 70 per cent of its water from the SNWD project. It used to obtain most of its water from aquifers below the city but, after years of increased pumping, the aquifers were close to depletion and the ground under the city had begun to subside.
About 3,600 gigalitres of water is consumed in Beijing each year and that is expected to rise to more than 4,000 gigalitres in the early 2020s. Surface water sources provide the city with 2,100 gigalitres and the SNWD brings an additional 1,100 gigalitres. Groundwater still makes up the difference. While the SNWD project has reduced pressure on groundwater sources, it has not alleviated it entirely and aquifers are likely to become a larger source of water as the city’s population continues to increase.
Rainfall has fluctuated in southern China since records began in 1961 but, according to one analysis of meteorological data, average annual rainfall has decreased significantly and average temperatures have increased at a rate above the global mean during the twenty-first century. That analysis also states that:
China is one of the countries where drought disasters occur frequently … The frequency of droughts had increased during recent years, especially in Southern China. High and very high drought hazard occurs frequently in most parts of Southern China and the drought risk in Southwest China even exceeds the national average … In 2003 and 2004, Southern China was affected by severe regional droughts. In 2006, there was a major once-in-a-century drought in Sichuan and Chongqing areas. From 2010 to 2013, South-west China suffered from drought for four consecutive years. From January to May in 2011, the precipitation in the middle and lower reaches of Yangtze River was the lowest compared with the same period historically in the previous 50 years.
The 2011 drought was so severe that water was released from the Three Gorges Dam to alleviate water shortages in the Yangtze delta. At that time, Hubei province, which was the most severely affected part of the country, had received 40 per cent less rainfall than the 50-year average. Irrigation and drinking water supplies were depleted, with more than 1,300 lakes officially declared “dead”. Shipping on a 228-kilometre stretch of the river was halted due to very low water levels. A similar response might be required if current conditions fail to improve.
The middle and lower portions of the Yangtze River basin are the main rice-growing regions of China. Parts of the region are so productive that two rice crops are grown per year. As the region is currently in the dry season, it is unlikely that the drought will significantly affect rice production. The 2011 drought, however, destroyed almost 100 million hectares of crops and cut drinking water supplies for 4.9 million people and 3.4 million livestock. That drought began in January 2011, several months later than the current drought, and intensified into May. The current drought began much earlier and, if it persists, could cause more damage than that of 2011.
