Quality of Raw Water for Singapore’s Water Treatment Plants in Johor

Mr Speaker, I would like to reiterate the written reply I had issued yesterday in response to Mr Seah Kian Peng's PQ.

PUB will shut down its Johor River Waterworks when the Johor River is affected by pollution upstream of our waterworks. Johor also has water treatment plants along the Johor River, upstream of the Johor River Waterworks, and will shut down their plants when pollution occurs upstream of them.

Since 2017, there have been seven pollution incidents along the Johor River which caused PUB's Johor River Waterworks to be temporarily shut down. These incidents have been traced to illegal discharges from premises such as palm oil mills and chicken farms within the catchment area. These pollution incidents typically cause disruptions ranging from several hours to several days. So far this year, there have been two pollution incidents, with the most recent one on 4 April 2019, where there were high ammonia levels in the Johor River.

Given the importance of the Johor River to the water supply of both Singapore and Johor, we have expressed our concern over the frequent recurrence of pollution incidents to Malaysia, both at the federal and state levels. Most recently at the Singapore-Malaysia Leaders' Retreat in April, Prime Minister Lee raised concerns over pollution in the Johor River and the severe impact of pollution incidents on both countries.

Under the 1962 Water Agreement, Singapore is entitled to draw 250 million gallons per day (mgd) of water from the Johor River, while Johor is entitled to buy treated water up to 2% of the total quantity of water we import to Singapore on any given day, or about five million gallons per day when Singapore draws its full entitlement. In practice, we have been selling Johor 16 mgd of treated water, which is in excess of their entitlement, at Johor's request. We do so on a goodwill basis without prejudice to our rights under the 1962 Water Agreement. When we are unable to import any water from Johor due to pollution, Singapore has no obligation to supply treated water to Malaysia.

During these pollution incidents, PUB works closely with the Johor authorities to flush the polluted water column from the Johor River. Such collaboration between PUB and its Johor counterparts has helped us to manage the pollution incidents. PUB conducts stringent water quality tests to ensure that the raw water from the Johor River is suitable for treatment before resuming abstractions and operations. During such temporary disruptions, PUB steps up production at desalination plants and local waterworks to meet Singapore's demand.

Nevertheless, pollution incidents along the Johor River impact the water supply of both countries and remain a serious concern. We will continue to engage our Malaysian counterparts on the need for them to take measures to prevent future pollution incidents along the Johor River.

May I ask the Minister whether there is any concern on the hazardous contaminants to health in the water supply from Johor? How vigorously do we check on the quality of the water from Johor? And lastly, does Singapore have any say on the factories' waste discharge in Johor that end up in the reservoirs supplying water to Singapore?

Both Singapore and Johor authorities check the water very vigorously. In fact, we are usually alerted by of our counterparts in Johor that the water is polluted, either with ammonia or other contaminants, before the water comes to us because the Johor plants are upstream. And indeed, they have to close down their plants before we do. And maybe a few hours or few days later, in coordination with our counterparts, we turn up operations at our plants.

We are not in control of how their land is allocated or where factories are but we certainly are in collaboration with both their Department of Environment as well as their waterworks to make sure that should incidents like this occur, alerts can be given early enough for both parties to act.