| Popis: |
Batu Kitang Submersible Weir (BKSW) was constructed to secure reliable water yield from the Sarawak Kiri River until 2010. However, ever-increasing water demand had outstretched the weir capacity. Upgrading work has been done to extend the weir height from 1.5 m to 2.5 m using interlocking concrete blocks to increase water storage capacity. However, the storage capacity and flood extend are unknown after the upgrading work. This study aimed to determine the effect of upgrading works on water storage capacity and floodplain coverage in the upper catchment using InfoWorks River Simulation (RS). Results revealed that weir height extension from 1.5 m to 2.5 m at BKSW had increased the water storage capacity from 1012 ML to 1499.62 ML, securing approximately 48% more water. Besides, maximum storage depth was also increased from 6.53 m to 7.53 m, and the distance of storage reservoir coverage from BKSW also increased from 8 Km to 16 Km. However, these increments would not lead to any significant impact on floodplain coverage upstream. It is novel to discover that a 1m weir height increase has extended BKSW service from 2010 to 2030 under a 1:50-year drought scenario. After 2030, various measures such as inter-basin raw water transfer should be implemented to increase the raw water supply and reduce water usage to ensure a sustainable water supply for Kuching City and its surrounding areas. |
