THE Ministry of Energy Transition and Water Transformation (PETRA) has reaffirmed its commitment to strengthening Malaysia’s water security through the broader utilisation of alternative water sources, with rainwater harvesting systems identified as a key initiative under the National Water Policy and the 2040 Water Transformation Plan.
Speaking in response to a parliamentary question from Senator Datuk Rosni Sohar in the Dewan Negara on Monday, Deputy Prime Minister II Datuk Seri Fadillah Yusof outlined the Ministry’s strategic approach to maximising rainwater utilisation during drought periods and monitoring the effectiveness of ongoing studies.
“PETRA is committed to reinforcing national strategies to expand the use of alternative water sources to ensure water supply resilience,” he stated.
The implementation of Rainwater Harvesting Systems (SPAH) aims to support sustainable water management, reduce demand for treated water, serve as a contingency during supply disruptions, and consume less energy compared with conventional sources.
The Ministry, through the National Hydraulic Research Institute of Malaysia (NAHRIM), has spearheaded several key interventions to promote SPAH across communities, government premises, and private sectors.
These include the development of the NAHRIM Tank Software 2.0 in 2021, which offers online simulations to determine optimal tank sizes and evaluate storage efficiency and potential water savings.
Fadillah, who also serves as PETRA Minister, explained that additional efforts include the 2017 Master Plan Study on Conjunctive Water Supply Systems in the Federal Territory of Kuala Lumpur to identify alternative water sources, including rainwater in urban areas, the publication of technical guidelines in 2014 for system components, and the legal incorporation of SPAH under amendments to the Uniform Building By-Laws 1984, adopted in 11 states across Peninsular Malaysia.
Physical SPAH projects have been executed in government and private buildings, residential areas, and communities, covering 16 projects since 2001, with installations including storage tanks, retention ponds, and IoT systems for monitoring. These projects have benefited over 1,000 users to date, tailored to local needs.
“Studies conducted by NAHRIM indicate that SPAH implementation has a direct effect on reducing flash flood risks in urban areas. For example, research in Taman Wangsa Melawati shows peak discharge reductions of 10% to 20%, while broader-scale adoption in the Damansara River Basin could cut flood-affected areas by 35% to 50%, depending on the storage capacity of each building,” the Ministry reported.
Furthermore, effective SPAH usage can save up to 30% of treated water by diverting rainwater for outdoor purposes, such as vehicle washing and landscape irrigation.
PETRA has committed to ongoing evaluation of the initiative’s effectiveness through impact studies, pilot projects for upgrading retention ponds for water supply, and assessments of user acceptance.
“The expansion of SPAH adoption will continue to enhance the nation’s resilience during droughts and ensure long-term water supply security,” Fadillah added.
