China Can Water Down Impact Of Floods

By Asit Biswas, Cecilia Tortajada 18 August, 2020

China has made great advancement in flood prevention but is it enough? Global water gurus Biswas & Tortajada expand

7/10 worst floods in past 100 years were in China - 5 in Yangtze & 2 in Yellow; the worst one, in Yangtze & Huaihe, flooded an area the size of England & half of Scotland & claimed 2mn lives
China is battling another serious flood - since June 2020, 433 rivers above danger levels & 34mn people affected; fortunately, China's made advancements in assessing risks & control infrastructure
Grey infrastructure like Three Gorges Dam (used 53 times to prevent floods) is now being used also with green infrastructure for a holistic approach; climate change will make things more difficult

The article was first published in China Daily in July 2020. Click here to view.

China has suffered from floods since time immemorial. In ancient China, when legend and history often intermingle, Da Yu, or Yu the Great, who could be considered as founder of the Xia Dynasty (21st century-16th century BC), is said to have tamed the floods of the mighty Yellow River, saving people from untold miseries.

The Yellow River is the second-longest river in China — after the Yangtze River — and the sixth longest in the world, and prone to frequent and serious floods.

7/10 worst global floods in China; 5 Yangtze & 2 Yellow…

China has had more than its fair share of floods. Of the 10 worst floods in the world during the past 100 years, seven have been in China — five in the Yangtze River (1911, 1931, 1935, 1954, 1998), and two in the Yellow River (1887 and 1938).

The world’s worst flood was in the Yangtze and Huaihe rivers in 1931. After two years of serious droughts, extreme rainfall in the densely populated Yangtze River basin caused the 1931 flood. It affected an area equivalent to the size of England and half of Scotland, forcing an estimated 40 percent of the affected population to leave their homes — with the resulting diseases and malnutrition claiming more than 2 million lives.

… China battling another serious flood since June 2020…

… Floods = ~40% of losses due to natural disasters

Floods are one of nature’s most destructive forces. Globally, floods are responsible for nearly 40 percent of all losses due to natural disasters. Between 1995 and 2015, the world witnessed about 3,000 floods, which affected nearly 2.3 billion people. From 1980, floods have contributed to more than USD1 trillion in global economic losses.

China has been battling another serious flood, with 433 rivers flowing above the danger levels since early June and 33 having crossed historically high levels. Also, more than 33.85 million people have been affected in 27 provinces and regions, and 141 people have either dies or are missing.

Worse, since major floods are more severe in late July or early August, the most dangerous period might not be over yet.

The flood situation in the middle and lower reaches of the Yangtze River is as bad as the massive floods in 1998, with the water level in Jiangxi’s Poyang Lake, the country’s largest freshwater lake, rising to 22.6 meters, higher than in 1998, on Monday.

Both President Xi Jinping and Premier Li Keqiang have said the Party and government officials’ top priority should be protect people from the floods, shift them to safer places and provide them with relief materials.

Flood impacts can be significantly mitigated…

… Three Gorges dam used 53 times to control floods

Floods cannot be prevented or completely controlled. But their impacts can be significantly mitigated, for which both infrastructure and soft solutions are essential. For example, the Three Gorges Dam has played an important role in mitigating floods in the Yangtze River. Between 2003, when the dam was completed, and 2019, it was used 53 times to control floods.

China has made great advancement in assessing risks, by studying the changes in flood-prone areas, and identifying ways to reduce those risks. And apart from making remarkable improvements in forecasting and monitoring floods, and strengthened its warning and communication system, China has built extensive flood-control infrastructure along rivers and developed ways to drain out floodwaters from cities as soon as possible.

Gray infrastructure such as dams, dikes, rainwater drainage systems, floodwater retention tanks, canals, and flood-proof buildings have become necessary in cities, and in recent years, they have been complemented by green solutions such as the sponge city programs, artificial wetlands, rain gardens and permeable pavements.

Additionally, with floods increasing in frequency and intensity, many city governments now require large constructions (buildings and factories) to build “underground tanks” to hold rainwater. Multiplied by thousands, such tanks can hold huge volumes of rainwater which otherwise would flood the streets, overflow the drains and flow into the sea.

Great advancements have been made but predicting extreme floods because of climate change will be a major problem for China & the world

A major problem China and the rest of the world face is how to determine the magnitude and duration of extreme floods that are likely to happen in the future because of climate change. Although meteorology and geophysics still don’t have a clear answer to that question, cities can strengthen their infrastructure and make necessary provisions to minimise the impact of floods on people and their livelihoods and the economy.

Further Reading

  • Flood Insurance in China: Lessons & Opportunities – Only 2% of the RMB147bn of losses from 2016 summer floods are covered by insurance. With various pilots since the 80’s failing, Liu expands on past & future role of flood insurance for CWR
  • Counting the Costs of Floods in China – With China in the midst of one of its worst flood episodes in history, Asit K Biswas & Cecilia Tortajada look at the significant social and economic costs of floods, and what can be done about them
  • Capital Threats Remain Post COVID – There is no vaccine for climate & water risks, yet some in the financial sector are still burying their heads. CWR’s Dharisho Mirando reminds us how our capital is at risk & steps we can take to reduce them while going green
  • How To Make Water Issues Matter To World Leaders – Except Singapore, no other leaders of any other country have shown sustained interest in water in the last 50 years. How can this paradigm shift? Global water gurus Biswas & Tortajada explore
  • Tackling Asia’s Water Challenges – Following China Water Risk’s new report highlighting Asia’s water challenges and the Hindu Kush Himalaya region, Cecilia Tortajada from the Lee Kuan Yew School of Public Policy calls for action from the investment community

More on Latest

Asit Biswas
Author: Asit Biswas
Professor Biswas is a leading authority on water, environment and development-related issues. He has been an advisor and confidant to Presidents, PMs and Ministers of 19 countries, six Heads of UN Agencies, two Secretary-Generals of OECD and several heads of IGOs and MNCs. He was also Director of Canada’s Department of the Environment. Asit co-founded the International Water Resources Association (IWRA), the World Water Council and the Third World Centre for Water Management and currently sits on the International Advisory Board of Pictet Asset Management and the Indian Institute of Technology and is Strategic Advisor to Singapore International Water Week as well as Distinguished Visiting Professor to the University of Glasgow. Asit is a distinguished Academician. With 950+ publications, his h-index of 44 makes him an ‘outstanding scientist’ and a Research Gate score of 41.89, puts him into the top 2.5% of all scientists across all disciplines globally. He founded the International Journal of Water Resources Development and is the author or editor of 88 books; his works have been translated into 41 languages. He has also seven Honorary Doctorates plus numerous prestigious global environment and water awards, ranging from the Aragon Environment Prize to the Stockholm Water Prize; Canada even named him Person of the Year in 1996.
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Cecilia Tortajada
Author: Cecilia Tortajada
Dr Tortajada is a leading international authority on urban water and wastewater management. She currently focuses on ensuring water future in terms of food, energy and environmental governance and ensuring water security through coordinated policies, which include water and natural resources management and water reuse. Dr Tortajada has advised major international institutions like FAO, UNDP, JICA, ADB, OECD, IDRC and GIZ, and has worked in numerous countries in Africa, Asia, North and South America plus Europe. She received the prestigious Crystal Drop Award and has been the only woman President of the International Water Resources Association during its 50 years of history. Dr Tortajada is currently a member of the OECD Initiative on Water Governance and juror for the Finnish Academy’s Euro One Million Millennium Technology Prize. She is also the Editor‐in‐Chief of the International Journal of Water Resources Development; Associate Editor of Water International; member of the Editorial Boards of the International Journal of Water Governance, Journal of Natural Resources Policy Research, and Urban, Planning and Transport Research Journal; as well as Editor of book series with Routledge, Springer and Oxford University Press. Cecilia has also authored and edited over 40 books by major international publishers. Her work has been translated into Arabic, Chinese, Farsi, French, German, Hindi, Japanese, Mongolian and Spanish.
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