TNB concedes ‘massive land clearing’ contributed to Ringlet Reservoir surge


TNB has conceded that siltation from “massive land clearing and farming activities upstream” contributed to the rapid increase of the Ringlet Lake water level and the sudden discharge of the overflow.

The Ringlet Reservoir area
The Ringlet Reservoir area

The “accumulation of siltation and sediment had reduced the reservoir’s holding water capacity”, said TNB in a statement.

I am not sure TNB can wash its hands so easily, though.

No specific mention of any logging activities? If you look at the map above, you can see lighter green patches in the Habu area/Bertam watershed, which suggests this could be secondary forest (in contrast to the darker green primary forest). Was the primary forest logged?

Who is responsible for supervising the integrity of the catchment areas and preventing such massive land-clearing?

If you are going to manage a reservoir or dam, surely you bear responsibility for protecting the water catchment areas from being degraded or compromised. You also have a responsibility to ensure that there is no risk to human life downstream and to prevent any encroachment in the path of emergency water overflows.

This reminds me about the water catchment areas in those dams they are building in Sarawak. Some time ago, Aliran had published an article pointing out that the establishment of plantations in the 1.5m ha water catchment area for the Bakun Dam could threaten the viability of the dam. There are also concerns about plantations upstream of the Murum Dam.

TNB press release


The rapid increase of the Ringlet Lake water level within a short period of time late Tuesday and early Wednesday is an exceptional situation for the Ringlet Reservoir, said TNB President/CEO, Datuk Seri Ir. Azman Mohd.

The unusually intense downpours on October 22 and 23 had brought huge volume of water to Ringlet Lake together with solid wastes, debris and siltation from the massive land clearing and farming activities upstream.

The rubbish clogged up the Bertam Water Intake, an outlet where water from the Ringlet Reservoir normally flows before entering the Bertam tunnel to an underground power generation units. Such accumulation of siltation and sediment had reduced the reservoir’s holding water capacity.

As a result, for the first time in the history of the 50 year old reservoir, water level surged at a rate of 1.5 ft per hour, which is three times more than the normal monsoon rain condition.

Surplus water had to be discharged in stages from Sultan Abu Bakar dam to avert the dam’s automatic full spillage through all four spillway gates that would have caused greater destruction to the occupants of Bertam Valley.

By design, a spillway gate is a dam protective structure used to provide the controlled release of water flow from a dam into a downstream river. Downstream area should be clear of people and structures.

Azman said given the challenge of these external factors, which were beyond TNB’s control, it was impossible to give advance notice to immediately evacuate the water release pathway other than what had already been done in the circumstances.

“While we could and should be continuously improving our Standard Operating Procedures (SOPs), given the circumstances we seriously doubt whether any SOP can be fully effective in averting such a disaster,” said Ir. Azman.

He also said that no one should have lived in the path of the dam’s water release and the weather elements together with the development activities are introducing greater unpredictability to the situation.

“We are continuously monitoring the situation and we experienced a rate of rise of water level of 1.2 ft per hour from 4 PM to 6 PM yesterday. A sudden blockage of the power station’s intake can trigger another catastrophe.
S.A. 2013/10/99 (HQ)

“The people living in the area are still not out of the woods yet as development activities that have caused Bertam reservoir to lose its water holding capacity continue to gain momentum.

“We don’t think anybody can guarantee the safety of the people at the site given the present conditions. Thus, they should be kept out of harm’s way and vacate the area,” he added.

28 October 2013

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5 Nov 2013 10.36am

Those people just reap the poison fruit with their poison seed. The hidden opportunities cost just backfire.

1 Nov 2013 11.22am

An expert has said that the Bertam Valley flood that claimed four lives and caused extensive property damage could have been avoided had a rainfall forecast system been established.

30 Oct 2013 12.49pm

TNB should check the electricity metre of Najib’s residence as it is reported that Najib incurred almost RM2 million of electricity a year.

30 Oct 2013 3.25pm
Reply to  Fazilah

He should pay himself and not from public fund.

Electrocuted by TNB
Electrocuted by TNB
30 Oct 2013 7.27pm
Reply to  Fazilah

This is leadership by example! What a shocking behaviour!

don anamalai
don anamalai
31 Oct 2013 10.57am
Reply to  Fazilah

The government forked out more than RM2.5 million to pay the utility bills for the Prime Minister’s residence in 2012!–rosmah-rack-up-rm25-million-utility-bill-in-2012&Itemid=2 In a written reply, Minister in the Prime Minister’s Department Datuk Seri Shahidan Kassim said the government spent RM2,237,788.13 for electricity and RM311,174.25 for water bills respectively last year for the Seri Perdana complex, which is the official residence of PM Najib Abdul Razak. DPM Muhyiddin Yassin, a total of RM865,458.56 was spent on electricity and RM 99,264.03 for water bills in 2012 official residence Sri Satria complex. This is not reported on Utusan, BH, NST, Metro, TV3, Awani.… Read more »