Special Report – Tackling potable water scarcity

The Greater Bay Area is facing a massive demand for fresh water, and potable water scarcity is a challenge that Guangdong has been dealing with. The Datengxia water conservancy hydropower project, which is currently in the pipeline, is seen as a key step, to be followed by additional measures

Macau Business | March 2023 | Special Report | Decarbonisation. When? How?


Guangdong, Macau and Hong Kong are still trying to find ways to improve cooperation and coordination within the Greater Bay Area (GBA). The difficulties are proportional to the potential that the project represents for each of the 11 cities. But there is at least one area that cannot wait. Or rather, where delays are reflected in the quality of life of millions of inhabitants.

Among the examples that could be given, the environment appears in the first line. The environmental challenges are numerous and can hardly be solved without the cooperation potentially provided by the GBA. An example is the scarcity of potable water – on which Macau is completely dependent.

Professor Joseph Hun-Wei Lee, who is simultaneously one of the leading international experts in Water Environmental Engineering and President of the Macau University of Science and Technology, shared with Macau Business readers some of his thoughts on this topic. “The water scarcity for Macau is related to seawater intrusion (from the ocean into the Pearl River/West River) in times of drought,” he concedes, “a problem that the Pearl River Water Resources Commission has been grappling with.” Also, the Ministry of Water Resources of China “is paying special attention to this in view of Macau’s strategic importance.”

“From the point of view of GBA, there is a water scarcity problem in some areas and contexts but on the whole the Guangdong province has much more water resources than other parts of the country,” Professor Lee explained.

The also Chair Professor of the Macau Environmental Research Institute believes that the solution lies precisely within the scope of the GBA and not in isolated solutions, such as central desalination centres, whose viability he questions. Although “always feasible” (Hong Kong is building one in Tseung Kwan O, he pointed out), “it has to make economic sense.”


“From the point of view of GBA, there is a water scarcity problem in some areas and contexts but on the whole the Guangdong province has much more water resources than other parts of the country” – Joseph Hun-Wei Lee

“The GBA has a huge demand for fresh water, not only for the survival of humanity but also for industrial and agricultural use,” according to Tianwei Hao, Professor in the Department of Civil and Environmental Engineering, University of Macau. “We need to look into alternative water supply, such as using seawater for flushing or air conditioning, in order to preserve fresh water,” he told recently to Macao Magazine.

At the end of last year, it became known that the water supply in Macau and Zhuhai was affected by high levels of salinity, which led the Pearl River Delta Water Resources Commission to activate an emergency plan. The drought and the increase in occurrences of salty tides that enter the interior rivers, in addition to the already usual salinity levels of the waters that supply the reservoirs of Macau and Zhuhai, led to the activation of the plan, which in one week solved the problem. The latest example: at the end of January, the Marine and Water Bureau warned of more severe salt tides this winter, which could affect the city’s freshwater supply. The head of the Bureau said she hoped that the region can persevere through the dry season.

So, the issue is structural. The new Datengxia water conservancy hydropower project, which will provide water supply for Macau and Zhuhai and is estimated to complete construction by the end of this year, could help, but a more structural intervention will be needed to tackle the problem.


Differences between Macau and Hong Kong.

Another idea Professor Joseph Hun-Wei Lee – also President of the 88-year-old International Association for Hydro-environment Engineering and Research (IAHR) – shared with us is that “Unlike Hong Kong, Macau’s water supply is privatized historically – i.e. supplied by Macao Water. This would be an important factor in the consideration too. Of course, ultimately water conservation and reuse are technical options (like what Singapore has done), but the above considerations also apply.”

The subject of the distinct difference between the two SARs in terms of managing local water resources was also addressed by Christine Loh, Institute for the Environment, the Hong Kong University of Science and Technology: “While Hong Kong continues to invest in water infrastructure to increase its local supplies, Macau relies on adjusting its tariff to manage demand. Hong Kong has not raised its water tariff since 1995 due to the inability of the authorities to pass legislation to increase prices and so has been unable to use the price mechanism to reduce consumption.”

In the long term, says the former Hong Kong Under Secretary for the Environment, “Hong Kong needs to review its pricing policy so it can invest in infrastructure and reduce consumption.”

“Both SARs also have an interest in participating in mainland China’s water resources management system to ensure their interests are protected, besides contributing to the overall sustainability of the entire watershed.”

The fact that the two SARs are linked to the upstream Pearl River watersheds, yet remain separate from mainland China’s water resources management system, may mean “in the long term, a threat to them as the supply and price of water could fluctuate.”

(Strictly speaking the two SARs are not part of the Pearl River watershed. While Hong Kong depends on the Dongjiang River for water, it is not part of the Dongjiang River watershed [in fact, the Dongjiang River water is transported 80 km through a dedicated pipeline to HK]. Similarly, Macau depends on the Xijiang River for water, but it is not part of the Xijiang River watershed, at least in the scientific sense).

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