KUCHING: Downstream towns are expected to experience a minimal rise in river levels with the releasing of water from the Bakun hydroelectric power (HEP) Dam today.
Sarawak Energy Berhad (SEB), in a press statement, said water is released through a spillway specially designed for this purpose when the reservoir level at the dam exceeds a certain point.
This controlled procedure ensures water is released at regulated volumes through the gated spillway over a duration of time, to achieve the required level in the reservoir, and to minimise the impact to the downstream regions, said SEB.
The released water is estimated to flow past Kapit town for about two days after the release, and Sibu town after four days. The rise in river level and intensity of flowing water will reduce as the distance increases.
On top of flood mitigation, the dam also holds river debris within the catchment, making downstream navigation much safer.
Over the period of release scheduled to commence today, the release will be kept as low as possible, and will cease once the water level at the reservoir normalizes, said SEB, adding it is a standard practice undertaken by hydropower operators worldwide.
In addition to generating electricity, hydropower dams such as Bakun HEP mitigate the impact of heavy rainfall on downstream flow by holding back large volumes of water in its reservoir.
Hydropower dams are capable of mitigating impacts from heavy rainfall within the upstream catchment.
However, other factors such as high sea tides, heavy rainfall downstream into catchments and tributaries of the Rejang can still result in floods, and are unrelated to the scheduled release.
Since the completion and impoundment of Bakun HEP in 2010, Sarawak Energy’s HEP operator Sarawak Hidro Sdn Bhd (SHSB) has managed the reservoir water level in this manner � holding back water throughout the year and slowly releasing the water in a regulated procedure when the need arises � and, in the process, helping to reduce major flooding downstream in areas such as Sibu.
Source: The Borneo Post