I did some research and picked up an article published by BERNAMA(source:
http://www.bernama.com.my/bernama/v3/news.php?id=198297 )
May 19, 2006 10:27am
Is the Sarawak River Barrage To Be Blamed For Massive Floods?By Linda Khoo Hui LiKuching, May 19 (Bernama)-- Is the Sungai Sarawak Barrage in Sejingkat to be blamed for the floods in 2003 and 2004?
The floods were the worst to hit Sarawak after 1963, where thousands in Kuching, Bau, Kota Samarahan and Sibu were evacuated. Many primary and secondary schools in low-lying areas were closed for days.
Kuching suffered severe losses in the 2003 and 2004 floods.
CRISTICISM, POLITICAL ISSUESDue to this massive losses, the Sungai Sarawak barrage had became the subject of criticisms and was turned into a political issue.
An opposition party claimed the barrage's failure to control the river's water level as the main cause of floods in the state's low-lying areas.
However residents gave the thumbs up for the Sungai Sarawak barrage.
A resident of Kampung Melayu Tabuan, one of the villages near the river's lower course, said before the construction of the barrage, floods would hit villages located along Sungai Sarawak at least twicw a month--during the 1st and 15th day in the Chinese calender.
SUNGAI SARAWAK REGULATION SCHEME
Kuching Barrage Management Sdn. Bhd. general manager, Captain Goh Chin Guan, said the barrage, which comprises the first-ever barrage and shiplock in South East Asian, a fly-over and two causeways-- one across Sungai Santubong at Bako and the other across Sungai Sarawak at Pending, is part of the Sungai Sarawak Regulation Scheme (SSRS)
The barrage's design was based on the 1963 flood situation, with input from british and danish experts. The structure has shown to be effective in mitigating floods in Kuching.
If not for the barrage, Kuching City could have been flooded on a number occasions, Goh said.
He said a sophiscated software system, known as MIKE II is the 'brains' behind all data collection and information needed to operate the barrage.
He said real-time water and rain fall data is collected by the telemetry system and based on computational model of the river. The predicted discharge and water level are two factors in deciding when to operate the barrage gates.
REMOTE STATIONS
Remote stations at various catchment areas, stretching from Padawan to Bau, where the Sungai Sarawak Kanan and Kiri start will exact the amount of rainfall and water level, he said.
All the data is available on computer and monitored contantly.
Man and technology are pitted against nature to help control the river's water level.
"Although we cannot control the weather but at least we have put in a system that gives us early flood warning. By then we are able to advise people to take necessary precautions," Goh said.
HIGH TIDE
Goh said this process would take about 5 hours and last until the high tide when the levels of water downstream and upstream of the barrage are about the same.
He said the 5 hour process of creating a reservoir to receive the water from the catchment is sufficient to prevent riverwater from overflowing the banks.
However, the barrage has its limitations especially when the rainy period coincide with the 'king tide' days.
When this happens, the gates will be left opened to allow free flow of water. With that, flooding time will be drastically shortened and limiting the areas affected.
The massive flood is a phenomenon caused by heavy rain and the 'king tide' that hindered discharge of floodwater into the sea.
"This is the cause of the massive floods that hit Kuching, Kota Samarahan and Bau in 2003 and 2004," Goh said, adding that the completion of the barrage has drastically reduces sedimentation on the riverbank, thus resulting in cleaner and clearer water.
I rest my case...
