As the Xi River (aka Si-Kiang or West River), the western tributary of the Pearl River in Guangdong, enters its flood season, Zhuhai has restarted the Guangchang Pumping Station to deliver raw water to Macau, marking the official end of the 2022-23 salt tide in the Pearl River estuary, according to a statement by the Marine and Water Bureau (DSAMA) yesterday.
Salt tide, according to Wikipedia, is a phenomenon in which the lower course of a river, with its low altitude with respect to the sea level, becomes salty when the discharge of the river is low during the dry season, usually worsened by the result of astronomical high tide.
The statement pointed out that with the gradual increase of water from the river, the salinity of the raw water outside the Guangchang Pumping Station, which is located the most downstream of the Pearl River for water supply to Macau, has gradually stabilised and has remained at a low level.
The statement said that during the salt tide, since 2020 the “Datengxia Gorge Water Conservancy Project” aided by Macau has been playing a role in the allocation of water resources in the middle basin, where usually the river runs in a zigzag through the land, providing nearly two billion cubic metres of water to the downstream, significantly increasing the possibility of fresh water drainage from the downstream estuary.
The statement noted that the saltiness of tap water in Macau has been maintained within 30 milligrammes per litre.
Meanwhile, the bureau pointed out that about 2,300 households participated in its Water Savings Incentive Programme, which ended last month.
The programme aimed to encourage local households to actively save water to cope with the salt tide threat.
This undated handout photo provided by the Marine and Water Bureau (DSAMA) yesterday shows the Guangchang Pumping Station in Zhuhai.
