Singapore has been supplying more drinkable water to Johor since last Friday, but this will not affect the country's own water supply, national water agency PUB said yesterday.
PUB said in a press statement that the Malaysian state's Sungai Layang dam has been severely affected by the current dry weather, and its water regulatory body, Badan Kawalselia Air Johor (Bakaj), had asked for help.
Over the years, PUB has, at Johor's request, supplied about 16 million gallons of drinkable water a day to Johor.
After Bakaj asked for help, Singapore agreed to temporarily raise the supply provided up to 22 million gallons a day since last Friday.
"This arrangement is temporary and subject to regular review, and this will not affect the water supply in Singapore," PUB said.
The water agency said that rain in Singapore - as well as increased production of Newater and treated sea water to meet local demand - has helped to keep water levels in reservoirs here healthy.
In contrast, Bakaj had to start water rationing in parts of Johor Baru on Sunday. The rationing will last until Sept 15.
Still, PUB noted that the water level in Linggiu Reservoir in Johor has also been affected by the weather and is at an all-time low.
It is now at 54.18 per cent of its capacity, down from 54.5 per cent two weeks ago, PUB said.
This is cause for concern as the reservoir's water level affects Singapore's ability to draw water from Malaysia's Johor River.
Under a 1962 agreement, the Republic can take up to 250 million gallons a day from the river.
Singapore built the reservoir upstream of the river in 1994, so that it can collect rainwater to push sea water back to the sea, ensuring Singapore's water supply.
Minister for the Environment and Water Resources Vivian Balakrishnan revealed earlier this month that, since the start of this year, PUB has had to stop drawing water from the river temporarily on 77 occasions, because of sea water intruding into the river.
He has called for Singaporeans to use less water, as a weather phenomenon called El Nino is expected to lead to even drier weather than usual for Singapore and Malaysia for the rest of the year, which will affect the water supply from the river as well as Singapore's own reservoirs.
Prime Minister Lee Hsien Loong had said earlier this month that he is watching Singapore's water stocks carefully.
He said on Facebook: "In Singapore, water will always be a precious resource. Never take it for granted, or waste it."