Written Answer by Ministry of National Development on Extension of Rainwater Harvesting Systems under HDB Greenprints @ Yuhua Programme to mature housing estates

Nov 2, 2020

Mr Murali Pillai: To ask the Minister for National Development whether HDB can explore the extension of rainwater harvesting systems, first piloted under the HDB Greenprint @ Yuhua programme, to mature housing estates so as to reduce the use of potable water for common area washing and watering of plants.

Answer:

As part of national water conservation efforts, HDB constantly explores new water saving initiatives for both new and existing estates. 

The Rainwater Harvesting System (RHS) pilot at Yuhua estate showed that the RHS was not cost-effective, as it involved the installation of a water tank and treatment systems at the ground level of each HDB block.  HDB has since developed the Urban Water Harvesting System (UWHS), which integrates the rainwater harvesting tank and treatment system with a detention tank to reduce implementation costs.  Besides allowing rainwater to be harvested for non-potable uses like the washing of common areas, the UWHS also slows down stormwater discharge to mitigate flood risk. 

HDB has introduced the UWHS to all suitable BTO projects launched from Aug 2018.  In addition, HDB will pilot the UWHS in some existing HDB estates under the HDB Green Towns Programme that was announced earlier this year.  HDB is currently working with PUB to identify suitable locations for the pilot, taking into consideration cost effectiveness and technical feasibility.  If the pilot is successful, HDB will roll out the UWHS on a wider scale in existing estates, where applicable.

HDB will continue to explore new practical water saving solutions to promote water conservation in HDB estates.