Flow and sediment yield simulations for Bukit Merah Reservoir catchment, Malaysia: a case study

Area of Science:

• Hydrology
• Environmental Science
• Water Resource Management

Background:

• Bukit Merah Reservoir is crucial for potable and irrigation water in Malaysia's Kerian District.
• The reservoir has faced significant water stress over the last two decades.
• Land-use activities are identified as the primary driver of sedimentation in the reservoir watershed.

Purpose of the Study:

• To simulate and quantify the impacts of land-use change on the Bukit Merah Reservoir watershed.
• To assess the effects of projected and hypothetical land-use scenarios on water resources.
• To understand the implications of these changes for reservoir operations.

Main Methods:

• Utilized the Soil and Water Assessment Tool (SWAT) for simulation and quantification.
• Calibrated the SWAT model for accuracy.
• Developed two land-use change scenarios: projected (2015) and hypothetical extensive change.

Main Results:

• Simulations indicate average water quantity will remain largely unaffected.
• A decrease in groundwater storage is projected.
• An increase in suspended sediment yield is anticipated.
• Results are based on 17 years of rainfall data.

Conclusions:

• Decreased groundwater storage and increased sediment yield will intensify operational problems at Bukit Merah Reservoir.
• Land-use management is critical for mitigating negative impacts on water resources.
• The study highlights the vulnerability of essential water sources to land-use alterations.