PETALING JAYA (THE STAR/ASIA NEWS NETWORK) - The water level at three dams in Johor, which supply raw water to treatment plants that serve about one million people in the state, are below the critical mark.
This comes about as the hot weather dries up parts of the country despite occasional thunderstorms in other areas.
The National Water Services Commission (Span) said the water level at the Lebam dam was at 15.9 per cent while that of the Upper Layang dam was at 21.8 per cent and Pulai 2 dam at 36.1 per cent as of last Thursday (April 18).
Some 100,000 people in Kota Tinggi, Tanjung Balau, Teluk Ramunia, Pengarang and Bandar Penawar depend on water processed at treatment plants that draw water from the Lebam Dam.
The Sultan Iskandar plant treats water for 600,000 residents in Pasir Gudang and the eastern part of Johor Baru, specifically Johor Jaya, Bandar Seri Alam and Permas Jaya.
Replying to questions from The Star, the commission said the hot weather also caused the water level at Sungai Sedili Kecil to drop.
This has caused a fall in treated water production at the Lok Heng water treatment plant in Kota Tinggi, which led to supply disruptions for 4,004 households and premises that ended last Sunday.
Falling water levels at Sungai Gembut has, meanwhile, forced the Sungai Gembut water treatment plant in Kota Tinggi to reduce the production of treated water.
The commission said the water operator, Ranhill SAJ, started a scheduled water supply programme on March 21 which ended last Friday for 6,041 households and premises.
Span said it would continue to monitor the water level of dams that supply water to treatment plants to ensure a continuous supply of treated water to consumers.
"Span urges state governments and water operators in all states to closely monitor the situation at dams and rivers which supply water to their respective treatment plants.
"This will allow early measures to be taken to deal with any possibility of water supply disruptions," the commission said.
Consumers should be careful in their water usage and avoid wastage, it said.
Span said the situation in Selangor was still normal, as the water levels at storage dams in the state were all above 79.2 per cent.
The water levels at dams in Perak, Penang, Negri Sembilan and Melaka were also all at normal levels.
According to the commission, the water level at Air Itam dam in Penang had risen from 49.9 per cent last month to 52.8 per cent as of last Thursday.
The Air Itam is the water source for Penang's Air Itam township, Paya Terubong valley and surrounding areas.
In Kedah, Span said a raw water supply shortage at the Tipah, Merbok and Headwork Gurun water treatment plants has led to supply disruptions to Merbok, Tanjung Dawai, Bedong, Semeling, Singkir, Gurun and its surrounding areas.
Syarikat Air Darul Aman, which is the state water operator, has supplied water to affected areas to help residents affected by supply disruptions.
The Malaysian Meteorological Department (MetMalaysia) said in a report on its website that the country entered the inter-monsoon period on March 19, which is expected to last until the end of May with the arrival of the south-west monsoon.
The inter-monsoon period typically sees heavy thunderstorms in the evenings in parts of the country while others mostly receive normal levels of rainfall.
The south-west monsoon will, meanwhile, see the peninsula and Sarawak receiving lower rainfall, with more dry days than wet ones in these areas.
There are four seasons in Malaysia - the south-west monsoon (May to September), north-east monsoon (November to March) and the two inter-monsoon periods in between.
MetMalaysia, in its website, also recorded 21 areas under heatwave alert as of last Friday.
These areas are Chuping (Perlis); Sik (Kedah); Pasir Mas, Tanah Merah, Jeli, Machang, Gua Musang and Kuala Krai (Kelantan); Kuala Terengganu, Hulu Terengganu and Dungun (Terengganu); Jerantut, Raub, Bentong, Temerloh, Maran, Pekan and Rompin (Pahang); Petaling (Selangor); and Jempol and Tampin (Negri Sembilan).
The department will issue a Category 1 or heatwave alert when temperatures in an area hits between 35 deg C and 37 deg C for three consecutive days.
Category 2 is when temperatures rise above 37 deg C for three days straight.
When this happens, the Energy, Science, Technology, Environment and Climate Change Ministry is empowered to declare a heatwave in that area.
This is to enable the authorities to take follow-up actions, such as the closing of schools.
When an area hits Category 3 (temperatures above 40 deg C for three days in a row), the National Disaster Management Agency will be notified and the Prime Minister can declare an emergency.