The Metropolitan Waterworks Authority (MWA) and the Royal Irrigation Department (RID) have jointly employed a technique, called “water hammer”, to flush seawater out of the Chao Phraya River in their bid to maintain the quality of tap water.

MWA governor Prinya Yamasit said Sunday that the technique, which is on trial, has worked to a certain extent in reducing salinity of river water, which is used to produce tap water for Bangkok and its suburbs.

He assured that the MWA and the RID have been closely monitoring the intrusion of seawater into the river and have been working out appropriate measures to manage the production of tap water.

He admitted, however, that he is concerned about the health of people suffering kidney diseases and those under strict recommendation from doctors to avoid salty food, as well as industries and hospitals, which need fresh water.

The ongoing drought, which will last until next May, has caused water levels in the country’s reservoirs to fall steadily, including the four main reservoirs; Bhumibol, Pasak Cholasit, Kwai Noi Bamrungdaen and Sirikit.

Less water in the main reservoirs will mean less water for release to flush seawater from further intruding into the Sam Lae area of Pathum Thani province, where raw water is drawn from the river for use in the production of tap water.