Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

Hurricanes player Xavier Numia and Black Ferns player Marcelle Parkes train in isolation at Polo Ground Park due to the coronavirus lockdown on May 06, 2020 in Wellington, New Zealand. New Zealand has been in lockdown since Thursday 26 March following tough restrictions imposed by the government to stop the spread of COVID-19 across the country. (Photo by Hagen Hopkins/Getty Images)

A model presents a creation from the Spring/Summer 2019 Women's collection by British designer Bill Gaytten for John Galliano fashion house during the Paris Fashion Week, in Paris, France, 30 September 2018. (Photo by Julien de Rosa/EPA/EFE)

Riot security forces clash with demonstrators as a motorcycle is set on fire during a protest against Venezuelan President Nicolas Maduro's government in San Cristobal, Venezuela May 29, 2017. (Photo by Carlos Eduardo Ramirez/Reuters)

A little girl holding her newborn sister waits for their turn in a queue during a vaccination campaign under the supervision of the Syrian Arab Red Crescent (SARC) humanitarian nonprofit organization, in the besieged Syrian town of Douma, Syria, 23 May 2017. According to a statement from SARC, in the city of Douma some 12,809 children under the age of five were immunized in a vaccination campaign to prevent measles and poliomyelitis. The campaign was the first of its kind with the participation of 100 volunteers. SARC has been delivering vaccines to 17 health centers approved for vaccination campaigns in towns and villages in the Eastern Ghouta area. (Photo by Mohammed Badra/EPA)

Female soldiers march during a military parade marking the country's Independence Day in Caracas, Venezuela, Wednesday, July 5, 2017. Venezuela is marking 206 years of their declaration of independence from Spain. (Photo by Ariana Cubillos/AP Photos)

A commuter holding his shoes rides on a tricyle through a flooded street, caused by a heavy downpour brought about by the southwest moonson, in Manila, Philippines on August 2, 2019. (Photo by Ted Aljibe/AFP Photo)

In this photo released by Xhinhua News Agency, a rescuer evacuates residents near the site of a chemical plant blast in Zhangzhou, southeast China's Fujian Province Tuesday, April 7, 2015. Six people have been hospitalized and hundreds of firefighters deployed to battle a blaze sparked by an explosion at Goure PX Plant that produces the toxic chemical paraxylene, officials said Tuesday. (Photo by Wei Peiquan/AP Photo/Xinhua)