Macau looks to expand recycled water use in Cotai

Macau plans to expand the use of reclaimed water in Cotai, with two new treatment facilities expected to begin supplying recycled water to leisure businesses and urban districts starting in 2029, director of the Marine and Water Bureau (DSAMA).

The push targets cooling systems and toilet flushing to supplement freshwater demand. The comments were made at the first meeting of the 12th Macao Water Customer Liaison Group (CLG).

Authorities said design work for Phase II of the Coloane Reclaimed Water Plant and the Artificial Island Reclaimed Water Station on the man-made island hosting the Macau checkpoint of the Hong Kong-Zhuhai-Macao Bridge will commence this year.

The plants are expected to begin operations in 2029 and 2030, expanding supply to Zone A, Plot P in the Areia Preta district, and leisure businesses in Cotai.

The introduction of additional supply will not occur until 2029 or later due to current capacity limitations.

So far, Phase I of the Coloane Reclaimed Water Plant, located at the southeast corner of the Seac Pai Van Reservoir on Coloane Island, has been operational for more than two months. It produces 2,500 cubic meters of reclaimed water daily.

According to DSAMA, average consumption from the Coloane plant stands at 1,500 cubic meters, with Seac Pai Van public housing accounting for 55% and the University of Macau 45%, representing 0.5% of overall water use.

Thus far, the bureau reported that residents have lodged virtually no complaints, with the reclaimed water achieving expected results. Notably, the water can only be used in buildings equipped with dual-pipe systems for toilet flushing and landscaping, such as those at Seac Pai Van and the University of Macau.

DSAMA reiterated that reclaimed water should be used for toilet flushing and landscaping. It added that once the technology matures and conditions permit, the bureau may consider expanding the use of reclaimed water to conserve precious freshwater resources. In the meantime, the bureau remains firm in not recommending recycled water for purposes other than toilet flushing and landscaping.

Reclaimed water is metered and priced 15% lower than regular tap water.

Regarding future expansion, DSAMA indicated that it is targeting Cotai leisure enterprises. Wong said the bureau has met with the water supply technology department of a suspended enterprise.

“We have already met with the water supply technology department of the suspended enterprise to discuss the matter. The enterprise has expressed its welcome to the introduction of reclaimed water, but we may need to take further steps to explore how to integrate our reclaimed water into their system,” Wong stated.

At the same event, Nacky Kuan, executive director of Macao Water, noted that first-quarter water use rose 1.7% year-on-year to 22 million cubic meters, driven by an uptick in Spring Festival tourists and a “new Cotai hotel.” Recycled water is targeted to account for 5% of total water use by 2030 and 10% by 2035.

Supporting green efforts, a solar-powered system at the Seac Pai Van plant began construction earlier this year. Solar panels, expected to be installed before the summer holidays, will generate 250,000 kilowatts annually, covering 3% of the plant’s energy needs, Kuan stated.

“In fact, all the electricity generated by solar will be returned to the Seac Pai Van Water Plant, and we expect to reduce its electricity consumption by 3% annually,” Kuan told the media.