Only high intensity rainfall can stop water rationing

Thanks to the increase in rainfall, of late, several areas in the Klang Valley have been able to get their regular water supply.

However, there are places where water rationing will continue until the end of this month after one of the longest-ever recorded dry spell during the first three months of the year.

Justifying the rationing, Syarikat Bekalan Air Selangor (Syabas) stated that the rainfall over some parts of the Klang Valley was not sufficient enough to replenish the dams such as Sungai Selangor Dam and Sungai Langat Dam.

Thus, the fourth phase water rationing measure, affecting a grand total of 1,340,231 households or 6.7 million people in the Klang Valley, had been implemented since April 4.

The Meteorological Department's Deputy Director General Alui Bahari was quoted as saying that April and October were usually the wettest months of the year with an average monthly rainfall of between 200 and 350mm.

Why water rationing during the wettest month of April? How long are we going to go endure this hardship and end the water woes?

'Medium rainfall not enough'

Expounding further on the situation, Association of Water and Energy Research Malaysia (AWER) President S. Piarapakaran said that as long as there was no high intensity rainfall, like the one that causes flash flood, water rationing exercise had to be continuously carried out.

Based on the rainfall pattern, he said many areas in the Klang Valley were still experiencing medium rainfall that was not enough to fill up water catchment areas.

"For example, if it rains only in 20 percent of the vast water catchment area, then it will take a long time to fill up the dam...," he told Bernama recently.

He elaborated that it all depends on the rainfall pattern in the next few weeks and the focus is on Sungai Selangor Dam, which controls 60 percent of the raw water needs in the Klang Valley.

Based on Selangor state government's criteria, if a particular dam reaches 55 percent of its capacity the rationing for that particular region will be stopped.

Recently, Lembaga Urus Air Selangor (Luas) director Md Khairi Selamat also stated that about 200mm of rain is needed to increase the water level at the Sungai Selangor dam to 55 percent from the current 37.38 percent to end the water rationing exercise.

If this level is not reached by April 30, Md Khairi said water rationing is expected to be extended until the required level reached.

'Impactful cloud seeding needs proper planning'

If this is the case, why was there no cloud seeding operation carried out at the beginning of the year to keep water levels in the dams at optimum levels.

And how far is the cloud seeding helpful during the dry spell?

In reply to this, Piarapakaran said: "Once cloud seeding is done, it must also rain in water catchment areas to fill up the dam. It must be tied up with proper planning for critical stage procedures.

"For example, if a dry season is taking place longer than usual, the particular dam's critical level can be increased to ensure emergency procedures are implemented way before a crisis really takes place," he said.

Besides that, he said the local climate is affected due to deforestation.

"A clear example can be seen in Bukit Larut now, the drop in water level for Air Kuning dam in the wettest part of tropical rainforest in Malaysia that has prompted water rationing in the wettest town in the country, Taiping," he remarked.

Therefore, Piarapakaran asserted that it was time to look back at the human capital at the public sector to manage such situations without pointing to the climate.

"You cannot remain where you are to mitigate problems... the current water issue calls for a crisis management," he said.