KOTA TINGGI • Two dams in the southern state of Johor state have worryingly low water levels amid a prolonged dry spell in Malaysia, prompting officials to urge residents to use water sparingly.

The Sungai Lebam Dam in eastern Johor, near Pengerang town, which normally has a water level of 14m, has seen its water level plunging to almost 2m below the critical point in recent weeks.

The level has fallen under the 12.7m critical mark to just 10.9m, Bernama news agency reported.

The dam currently has enough water to last residents for about 70 days, said Johor's International Trade, Investment and Utilities Committee chairman, Mr Jimmy Puah Wee Tse.

The water level at another major dam south of Kota Tinggi town, called Lok Heng, is now just 50cm above the critical level of 1.5m.

Mr Puah said there are about 100,000 residents in and around Kota Tinggi, including in areas such as Pengerang and Teluk Ramunia.

He said that the state government has a backup plan to help the areas overcome the low water levels.

"We will dig three tube wells in the area near the dam," he told reporters, as quoted by Bernama. The wells are expected to supply 0.9 million litres of underground water as a backup for the Lok Heng area.

Singapore gets part of its water supply from the Linggiu reservoir, which is separate from the Sungai Lebam and Lok Heng dams.

Mr Puah told the media last week that the Johor government is working closely with water operator Ranhill SAJ and the Johor Water Regulatory Body to monitor the water supply situation amid a long dry spell.

Malaysia has been hit by a heatwave in recent days, forcing the Education Ministry to advise schools to monitor outdoor activities and ensure students drink lots of water.

Outdoor activities should be halted if it is too hot outside, the ministry said.

The dry spell is expected to last till April, and is a regular weather phenomenon that begins at the tail end of the north-east monsoon.

Meanwhile, the Malaysian Meteorological Department issued a Level 1 heatwave alert on Monday for 10 areas in the country after high temperatures were recorded for three consecutive days.

The states affected are Perlis, Kedah and Perak in the north, Johor in the south, Pahang in east Malaysia, and the capital city Kuala Lumpur.

Malaysia has a three-tier colour-coded warning system for heatwaves.

The Level 1 alert is triggered when the mercury climbs to between 35 deg C and 37 deg C for three days in a row.

Level 2 is triggered when the temperature goes above 37 deg C for three consecutive days.

When this happens, the Ministry of Energy, Science, Technology, Environment and Climate Change is empowered to officially declare a heatwave in that location, allowing the authorities to close schools.

When temperatures hit 40 deg C and above for the same duration, a Level 3 alert is issued and the Prime Minister will declare a state of emergency.

Johor, however, is not the only state worried about the water levels in its dams and reservoirs.

In Sabah, where water reserves at the major dams are still at a comfortable 80 per cent, eight major rivers have plunged to critical levels, and another nine have hit "alert" levels, the New Straits Times newspaper reported yesterday.

Sabah has only two months of water supply remaining due to the dry spell, warned the state's water department director Amarjit Singh.

He said the department will resort to cloud seeding should the dry spell persist.

In Perak, the Public Amenities and Infrastructure Committee chairman Abdul Yunus Jamhari has requested paddy farmers in Kerian, the main paddy farming district in the state, to monitor their water usage due to the dry weather.

"If we waste water in our paddy fields in the current hot weather, it could affect our crops," he was quoted as saying by Bernama.

And as the mercury soars in Kuala Lumpur, data from the Selangor Water Management Authority website shows that the water level in Sungai Selangor Dam - which supplies 70 per cent of the treated water in the capital and its surrounding areas - was still very high, at 98 per cent on Monday, The Star reported.