More groundwater than what is being extracted by the Water Services Corporation is already lost naturally to the sea. Recovering this huge amount of water could be the answer to Malta’s water problems, says geologist PETER GATT
James Debono
The Malta Resource Authority’s annual report in 2003 claimed 23 million litres of groundwater were being lost to the sea through natural underground leakages. It’s an amount that is higher than the 15 million litres of groundwater extracted by the Water Services Corporation.
But geologist Peter Gatt contends that Malta could tap this resource to provide an alternative to the illegal extraction of groundwater, whose increasing salinity is rendering it useless for agricultural use.
“These leakages are happening everywhere, but because of specific geological conditions it is very likely that these are concentrated in particular areas,” Gatt says, who points out studies from the 1970s by a German firm had already identified particular areas where these leakages of fresh water occur.
This flow of groundwater to the sea is a natural process which has been occurring for the past millennia, especially in islands like Malta that are rich in limestone deposits. “Malta is a limestone country which is very porous… its aquifer is held within the pores of this limestone which comes in direct contact with the sea. Therefore this results in a natural flow from the aquifer in to the sea.”
But detailed geological assessment is necessary to identify these spots to tap leaked groundwater. “If we manage to tap these flows before this water reaches the sea, we will be having a sustainable extraction of fresh water, possibly in very large quantities.”
Recovering this supply of water does not even require large-scale investment. “This is a simple, low-cost solution as it does not involve huge engineering projects… What it requires is a massive input of scientific research and assessment something which is very lacking in Malta.”
This solution is already being applied in countries like Syria, where geologists are extracting fresh water from offshore areas through boreholes in spots where fresh water from the mainland is flowing.
For Gatt, the presence of such an immense flow of groundwater flowing to the sea is evidence that catastrophic scenarios envisioning the disappearance of groundwater in five years’ time are not feasible. “It has been estimated that this flow of water is actually much greater than the amount of water extracted by the Water Services Corporation. So how can we speak of the demise of our aquifer when there is this huge amount of water which is being drained into the sea?”
Gatt is also sceptical of predictions that are not based on hard scientific evidence. “We do not have the minimum of scientific data about our aquifer. Which means we cannot really make such a prediction.”
Malta’s groundwater resources are still being negatively affected by the increase in salinity from intruding sea water into the aquifers, which spells disaster for farmers who will not be able to use this source in the fiture.
Gatt says the average 1,000 ppm (part per million) salinity already exceeds the European threshold for chlorides. In areas where a lot of extraction is taking place, the salinity might even reach 8,000 ppm.
Gatt says the salinity can be reversed if free extraction from boreholes is cut down. “Water has to be given a value because there is a cost to the environment when one extracts water. However the demand for water will remain. And we have to provide an alternative source.”
One of the options currently considered by the government is that of recharging the aquifer with water from sewage treated plants. But even here, Gatt warns this might be dangerous: “If you pump that water in the aquifer one could end up increasing the salinity of fresh water and possibly introducing dangerous substances in the aquifer.”
What irks him is that such decisions are being taken in the absence of a public entity responsible for Malta’s geological resources: “Malta is the only EU and Mediterranean country without a geological service.”
Malta’s last detailed geological assessment was carried out by the British. “They were the first to identify the Maltese aquifer and to construct the water galleries to exploit the best parts of the aquifer.”
Now it seems Malta’s colonial edge has been lost altogether. Clearly, it’s all water under the bridge now. jdebono@mediatoday.com.mt
Any comments?
If you wish your comments to be published in our Letters pages please click button below. Please write a contact number and a postal address where you may be contacted.
Search:
MALTATODAY
BUSINESSTODAY
Download MaltaToday Sunday issue front page in pdf file format
