“The water supply outlook for this winter and next spring is not optimistic and it is imperative that the entire city starts saving water.”

The Shenzhen Water Authority expects a shortfall of 1 million cubic metres (264 million gallons) per day until the spring, and hopes to make up half the deficit from emergency reserves and the rest through conservation.

Though residents may not feel it, Shenzhen has always been short of water because it has no large rivers, and its water containment capacity is low, according to Wei Fulei, deputy director of the Silver Lake New Energy Strategy Research Centre, a local think tank.

“Shenzhen’s average per capita share of water resources for 2019 was 154 cubic metres, which is only one-tenth of the average in [the whole of] Guangdong province, and one-thirteenth of the national average,” Wei said.

Water levels in the reservoirs in the Dongjiang area had fallen by 55 per cent, which was cause for concern, he said.

Xiong Yang, a water-treatment engineer and director of local NGO Green River, said the government might have to adopt harsher measures such as rationing if the situation worsened, which explained its conservation push before the shortage became dire.

02:13

More droughts and floods expected, billions of people to face insufficient access to water

More droughts and floods expected, billions of people to face insufficient access to water

Industrial and municipal uses such as landscaping and public hygiene currently accounted for the bulk of water consumption in Shenzhen, Xiong said. He called for a more reasonable allocation of water resources, such as reduced use of high-pressure water guns for urban cleaning.

Wei expected the shortage to ease with rainfall in the spring, but noted that Shenzhen’s heavy reliance on support from other parts of Guangdong province was likely to create problems, and the government needed to look for other solutions.

Provincial capital Guangzhou has also announced emergency measures to deal with increased salt tides, where the water supply becomes increasingly saline due to a lack of fresh water.

In 2019, the Guangdong government started a river water diversion project, to channel water from the Xijiang to the Pearl River Delta region. The Guangzhou portion of the diversion project has been completed but the Shenzhen part will only become operational in 2024.

“We also have alternative suggestions, such as considering seawater desalination or using reclaimed water, to gradually reduce dependency on water resources from the outside areas,” Wei said.