Straits Times Forum 3 Jun 2013
STUDYING the potential of tapping underground water sources would be a waste of money, and national water agency PUB should not embark on such an exercise ("PUB calls for tender on studying groundwater potential"; April 27). The consequences could be disastrous.
First, the ecosystem of underground aquifers is complex and fragile, and once disturbed, the change is generally irreversible.
Singapore is a small island and the quantity of water that can be extracted from underground aquifers would be very limited.
Also, any suggestion that the aquifers in Singapore could be topped up by rainwater is wishful thinking.
In recent years, large tracts of land have been covered by concrete as more developments have been built.
The ground areas that allow rainwater to permeate through are thus very limited.
Once groundwater is extracted, there is no way to replenish the supply.
In addition, Singapore is a small island surrounded by the sea.
Once freshwater is pumped out, saltwater intrusion into the aquifers could easily occur, resulting in salination of the remaining groundwater.
There are several famous "sinking cities" around the world - Shanghai, Houston and Mexico City, to name a few.
The main reason why they are sinking is the extensive extraction of water from underground aquifers for human consumption.
If we ignore the experiences of these cities, we could be on our way to creating a sinking island.
Wong Ming Keong (Dr)
