Regulated Release of Water from Bakun HEP Reservoir to Commence 8 September


Sarawak Energy is commencing its seasonal controlled release from the reservoir upstream of the 2,400MW Bakun Hydroelectric Plant (HEP) from 8 September 2021, for five weeks, until water level in the reservoir normalises.

Bakun reservoir levels are managed by releasing water at regulated volumes through gated spillways. This controlled procedure is conducted on a seasonal basis after permission is secured from the Sarawak Rivers Board, with the communities notified at least two days ahead of the scheduled release.

Over this period, the release volume is kept as low as possible, balancing both the upstream reservoir and downstream river levels to minimise the impact to the downstream regions.

Bakun HEP is owned and operated by Sarawak Energy, and together with the 944MW Murum HEP, forms a cascading system ensuring strong operational synergy in terms of operations and maintenance. They play a major role in mitigating the severity of flooding downstream of the Rejang River by balancing both upstream reservoir and downstream water levels especially during periods of heavy rainfall.

Since the completion of Bakun, downstream flooding has been reduced and the impact mitigated as the dam holds back a large volume of rainwater all year round.

Controlled release from reservoirs is a standard practice for hydropower operators worldwide and has been undertaken by the operator of Bakun since it was commissioned in 2011.

File photo: Small water release from the 2,400MW Bakun Hydroelectric Plant during spillway gate checking in 2020.