Singapore’s Fifth ‘National Tap’ May Draw on Groundwater

Looking to add a fifth “national tap” to Singapore’s existing four, national water agency PUB announced yesterday that it was looking to study the possibility of drawing on “naturally occurring aquifers and groundwater” in the area of the Jurong Formation. Aquifers are underground layers of water-bearing permeable rock or unconsolidated materials, such as sand, from which groundwater can be extracted.

The PUB has called a three-year consultancy services tender to study the potential of tapping on aquifers and other underground water sources in the western and southern part of the island, which contain rock deposits called the Jurong Formation. The study will look at the development of groundwater flow models, field investigation programmes and validation studies.

The tender will be awarded in July. PUB declined to review the budget for the study. Singapore’s current four “taps” are the local catchment areas, imported water, desalinated water and reclaimed water, known as NEWater. The PUB said that water demand here will nearly double by 2060 — from about 400 million gallons a day currently — of which about 70 per cent of demand will come from the non-domestic sector. With “competing demands for land”, the PUB said, it would be “challenging” to build new reservoirs to meet Singapore’s water needs.

“Based on knowledge of other rock formations worldwide and from observations made during engineering work, it may be possible that the Jurong Formation could host a deep, confined aquifer which could be less prone to surface pollution or subsidence,” the PUB said.

The agency noted that advances in geophysical exploration methods over the last few decades make surveying today “more effective than in the past” and will help in the study. PUB Chief Technology Officer Harry Seah said “extraction of groundwater will only be carried out if the risks of groundwater extraction can be adequately managed with no impact on existing buildings and infrastructure.”  This will be verified by the models that will be developed in the study, he added.

The PUB has also embarked on a study to verify the feasibility of extracting groundwater from reclaimed land in Jurong Island. The project has been awarded and commenced earlier this month.

Additionally, the PUB is finalising the appointment of an international expert panel on hydrogeology to “give guidance and direction on its underground water exploration endeavours”.