PETALING JAYA: Despite the many benefits of rainwater harvesting in residential units, and the system being mandatory in some new projects, the practice has not caught on with most Malaysians.
While some developers are all for it, others have concerns that include added costs.
Mah Sing group chief executive officer Datuk Ho Hon Sang said the company has been incorporating the feature in its developments since 2010, adding that the benefits of this sustainable practice outweigh the costs.
“Rainwater harvesting reduces dependency on freshwater sources, particularly in times of water scarcity, is also cost-effective for the end user, promotes water conservation and, of course, has a lower environmental impact,” he noted.
Apart from helping preserve local water resources, it also minimises the need for new infrastructure development, he added.
Homeowners could use rainwater for “non-potable purposes” like watering their plants, flushing the toilet, washing the car, and even laundry, “thus helping them to reduce their water bills,” said Ho.
There are also far-reaching effects that concern stormwater runoff management.
“Rainwater collection reduces the volume of water entering the stormwater drainage system, lowering the risk of floods and easing the pressure on local infrastructure during heavy rains,” he added.
Ho said there are several important factors to consider when building and installing a rainwater harvesting system.
These include the catchment surface size and roof design, which would determine the amount of rainwater collected.
“The roof material should be suitable for rainwater collection and devoid of contaminants that would affect water quality.
“The size of the storage tank should be based on the estimated water usage and space on the residential property. And it should be placed on a stable and levelled surface, able to prevent contamination and easily accessible for maintenance and cleaning,” he added.
According to Ho, a rainwater harvesting system is compulsory for new developments in Kuala Lumpur but is only encouraged in Selangor.
Perak housing developer Tony Khoo said such a system would come in handy for housing projects in Selangor, Kuala Lumpur and Penang, where water disruptions are not uncommon.
However, he pointed out the cost implications of installing rainwater harvesting devices in housing projects, with rising prices a concern.
“The cost will be passed down to the homebuyers by developers and contractors.”
Khoo said he hopes the government will consult with developers before mandating the installation of rainwater harvesting systems in housing projects.
“Why should rainwater collecting and utilisation technologies be included in housing projects? If the goal is to save energy, filtering rainwater necessitates the use of electricity, which does not result in savings but increases the cost,” he said.
Under the Local Government Department’s Guidelines for Rainwater Harvesting and Utilisation System, local governments will not approve residential development plans that do not contain a rainwater harvesting system.
The guidelines became mandatory after the National Council for Local Government approved them in 2011.
Meanwhile, Association of Water and Energy Research Malaysia (Awer) president S. Piarapakaran urged the government to make water-efficient labels compulsory.
“While it is currently voluntary, we recommend that the government implement a minimum water efficiency standard.
“Products that do not meet the minimum standards should be prohibited in the Malaysian market,” he said, adding that Singapore and some European countries practise static water efficiency to reduce water consumption.
“Electrical equipment that meets the mandatory efficiency requirements can be rapidly replicated in the water sector,” he said, adding that this technique will save a substantial amount of water.