TNB: Water release from Ringlet dam inevitable
BernamaPublished: Oct 28, 2013 3:46 PM | Updated: Oct 29, 2013 2:50 AM
The rapid increase of the Ringlet Lake water level within a short period of time late last Tuesday and early the next day was an exceptional situation for the Ringlet Reservoir, Tenaga Nasional Bhd (TNB) president and chief executive officer Azman Mohd.
The unusually intense downpours on Oct 22 and 23 brought huge volumes of water to the lake, together with solid wastes, debris and silt from what was described as massive land clearing and farming activities upstream, Azman said.
The rapid increase of the Ringlet Lake water level within a short period of time late last Tuesday and early the next day was an exceptional situation for the Ringlet Reservoir, Tenaga Nasional Bhd (TNB) president and chief executive officer Azman Mohd.
The unusually intense downpours on Oct 22 and 23 brought huge volumes of water to the lake, together with solid wastes, debris and silt from what was described as massive land clearing and farming activities upstream, Azman said.
The rubbish clogged up the Bertam Water Intake, an outlet where water from the reservoir normally flows before entering the Bertam tunnel to underground power generation units.
Such accumulation of silt and sediment 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 1.96 feet per hour, which was 13 times more than the normal monsoon rain condition," Azman said in a statement released in Kuala Lumpur today.
According to the statement, surplus water had to be discharged in stages from the Sultan Abu Bakar Dam to avert its automatic full spillage through all four spillway gates that would have caused greater destruction to the occupants of Bertam Valley.
Four people were confirmed dead following the flash flood that occurred when Sungai Bertam overflowed with the release of water from the Sultan Abu Bakar Dam, Ringlet, Cameron Highlands, on Oct 23.
The incident also destroyed about 80 houses and several cars in the Bertam Valley settlement areas.
The TNB statement explained that 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.
The downstream area should be clear of people and structures, it added.
Challenge of external factors beyong TNB's control
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 continually improving our standard operating procedures (SOP), given the circumstances, we seriously doubt whether any SOP can be fully effective in averting such a disaster," he said.
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, had introduced greater unpredictability to the situation.
"We're continually monitoring the situation and we experienced a rate of rise of water level of 1.2 ft per hour from 4pm to 6pm yesterday. A sudden blockage of the power station's intake can trigger another catastrophe.
"People living in the area are still not out of the woods yet, as development activities that have caused the Bertam reservoir to lose its water holding capacity continue to gain momentum," he said.
"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," Azman added.
- Bernama
The unusually intense downpours on Oct 22 and 23 brought huge volumes of water to the lake, together with solid wastes, debris and silt from what was described as massive land clearing and farming activities upstream, Azman said.
The rubbish clogged up the Bertam Water Intake, an outlet where water from the reservoir normally flows before entering the Bertam tunnel to underground power generation units.
Such accumulation of silt and sediment 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 1.96 feet per hour, which was 13 times more than the normal monsoon rain condition," Azman said in a statement released in Kuala Lumpur today.According to the statement, surplus water had to be discharged in stages from the Sultan Abu Bakar Dam to avert its automatic full spillage through all four spillway gates that would have caused greater destruction to the occupants of Bertam Valley.
Four people were confirmed dead following the flash flood that occurred when Sungai Bertam overflowed with the release of water from the Sultan Abu Bakar Dam, Ringlet, Cameron Highlands, on Oct 23.
The incident also destroyed about 80 houses and several cars in the Bertam Valley settlement areas.
The TNB statement explained that 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.
The downstream area should be clear of people and structures, it added.
Challenge of external factors beyong TNB's control
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 continually improving our standard operating procedures (SOP), given the circumstances, we seriously doubt whether any SOP can be fully effective in averting such a disaster," he said.
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, had introduced greater unpredictability to the situation."We're continually monitoring the situation and we experienced a rate of rise of water level of 1.2 ft per hour from 4pm to 6pm yesterday. A sudden blockage of the power station's intake can trigger another catastrophe.
"People living in the area are still not out of the woods yet, as development activities that have caused the Bertam reservoir to lose its water holding capacity continue to gain momentum," he said.
"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," Azman added.
- Bernama
View Comments0