Malaysia and Singapore will take further steps to guarantee the crucial supply of water from the stressed Johor River, said Singapore's Minister for the Environment and Water Resources Masagos Zulkifli.
He said the prime ministers of both countries had resolved on Tuesday, at a Leaders' Retreat, to take "timely and appropriate measures" to augment the supply of natural water to the Johor River.
While he did not reveal what measures would be taken, he said Malaysia and Singapore will look at "many schemes that have already been proposed", and decide based on technical feasibility, cost and speed of implementation.
Mr Masagos made the comments after an annual meeting here with his Malaysian counterpart, Natural Resources and Environment Minister Wan Junaidi Jaafar.
The Straits Times reported in May that Johor is studying plans to divert water from two rivers to the Linggiu Reservoir located upstream of the Johor River to ease water shortages that have hit the state in the past few years. The reservoir collects and releases rainwater, pushing seawater back into the sea to ensure the river water is not too salty to be treated.
One of Singapore's four taps besides reclaimed water (Newater), desalinated water and local catchment water, the Johor River supplies nearly 60 per cent of the Republic's current water needs.
But dry weather this year has raised fears over whether Singapore can continue to rely on Malaysia for the 250 million gallons per day of raw water under a water agreement which runs until 2061.
Yesterday, Mr Masagos noted that despite installing a barrage over the river mouth to prevent the intrusion of salt water, fresh water levels were still precariously low.
The Linggiu Reservoir was currently at 26 per cent of its capacity, he said. The reservoir was at 80 per cent at the beginning of last year, and 35 per cent in April this year.
"On the back of the dry monsoon season next year, it is probably not going to recover very quickly," he told reporters. The dry monsoon season usually runs from May to September, but has been affected by climate change. This year, for example, the reservoir started to dry up around March.
Mr Masagos said the barrage is now fully operational mechanically - automatic deployment will begin only in March - increasing the yield of treated water as plants no longer need to be shut down when the river gets too salty.
"What that means is that salinity intrusion has been resolved. I have been monitoring, and it has been very effective. But the natural flow of the Johor River is not enough to meet the needs currently of the Johor population as well as the Singapore population should Linggiu dam fail," he said.
Under the two countries' water agreement, Singapore is obliged to sell 5 million gallons of treated water to Johor each day. But PUB this year provided Johor with up to 22 million gallons of water a day as the state was forced to undergo rationing.
Yesterday, delegations from the two countries discussed issues such as land reclamation works in the Strait of Johor and efforts in combating haze.
Both Mr Masagos and Datuk Seri Wan Junaidi told reporters that all stakeholders need to recognise that the ecology of the waterway is linked to the value of developments along the shared strait, and it is in everyone's interest to take environmental concerns seriously.
On the haze, Mr Masagos said he was confident the Asean road map on transboundary haze would lead to a "haze-free Asean" by 2020.
Correction note: In an earlier version, we said the amount of water provided by PUB to Johor this year was up to 16 million gallons of water a day. This is incorrect. It should be 22 million gallons of water a day. We are sorry for the error.