Developing functional environmental flows – the River Baleh project (Sarawak)
The River Baleh is a headwater tributary of the Rajang, Malaysia’s largest river. The Baleh Hydroelectric Dam will be fully commissioned in 2025 and will generate 1285 MW of renewable energy. Sarawak Energy Berhad (SEB) is committed to developing the Baleh dam in a responsible manner, and follows the International Hydropower Association’s sustainability protocols. These protocols include undertaking comprehensive environmental impact assessments (EIA) of proposed dams and putting in place methods to mitigate any potential social or environmental impacts. This project is funded by SEB, and forms part of the EIA. It aims to identify the discharges that are needed to help ensure habitat integrity, the project will form a baseline against which future changes can be assessed. It is focussed on flow hydraulics, fluvial processes and thermal conditions in the river, and how these are influenced by the river’s current (pre-dammed) flow regime. It also involves modelling of catchment hydrology, to understand how land cover change is affecting flows and fine sediment runoff. It involves a combination of remote sensing, field-based surveys and monitoring, along with predictive modelling of hydraulic conditions and sediment dynamics. The project supports Celine’s PhD and Zoe Lum’s MRes.