In 2012, Malaysia quietly amended its Uniform Building By-Laws to require rainwater harvesting systems — Sistem Pengumpulan Air Hujan, or SPAH — on a class of qualifying buildings. The Ministry's intent was simple: cut peak demand on treated supply, ease pressure on storm drainage during convective rainfall, and shift the country onto a more resilient water footing.
Fourteen years on, the implementation gap is the most striking thing about the policy. Field surveys conducted by district enforcement officers in 2024 found that fewer than one in three qualifying buildings had compliant SPAH systems in service at the time of inspection. Most had something installed at CCC stage and removed by occupants within twelve months.
The law has been on the books for fourteen years. It is among the least-recognised pieces of building regulation in the country.
What SPAH Actually Requires
The legal text is short and the requirements are mechanical. A qualifying building — defined by roof area, occupancy type and intended use — must have a rainwater catchment system meeting minimum storage volume, first-flush diversion and overflow management. The requirements are scaled by roof area; a typical terrace house lands in the smallest qualifying bracket.
What the law does not specify, deliberately, is the system technology. Pumped systems, gravity-fed systems and hybrid configurations all qualify, provided the storage volume, diversion and overflow conditions are met. This neutrality was a virtue at drafting; in practice it has become an opening for the cheapest compliant configuration to dominate — even when the cheapest configuration is the worst long-term proposition.
The Local Authority's Position
Council enforcement has been uneven. Where SPAH is checked at CCC stage, contractors install the smallest qualifying tank, route a basic catchment to it, and book the inspection. The Council, working through a backlog and without dedicated SPAH inspectors, signs off on the visible installation. Occupants, taking possession of a finished house, often remove the tank within the first year — either because it occupies prime garden space or because the contractor never explained what it was for.
Senior Fellow Response
Candidate 2
Principal Fellow, Water Science
“Candidate 3's read is correct. Our compliance data from Penang puts post-CCC removal at roughly 60% in the first 18 months — almost identical to the national figure. The intervention point is owner education at handover, not the law itself.”
The Pump-Free Argument
Pumped systems lose their compliance value at the moment of a power outage. They also incur recurring cost: replacement pumps, electrical service, monthly draw. For a homeowner running an honest household budget, the SPAH tank that came with the house is, in operating terms, a small line item against the water bill it was supposed to reduce.
Gravity-fed systems — properly sized, properly mounted — sidestep both problems. They impose no operating cost. They keep working during the very events that motivate the law in the first place. The trade is that they require thoughtful placement at design stage, which means SPAH should be a design conversation, not a CCC checkbox.
What Should Change
- SPAH should be checked at handover by an inspector independent of the developer, not at CCC by an overstretched local authority.
- Occupants should receive a one-page document at handover explaining the system, its operating principles, and the legal status of tampering with it.
- The technology-neutrality of the by-law is correct, but the inspection regime should require evidence of operation, not just presence.
None of this requires new legislation. It requires the existing legislation to be treated as legislation.
Candidate 3 is the former senior government policy practitioner and a Senior Fellow at Voda Water Watch. He writes here in his personal capacity. The views expressed are his own.