An island in hot water

Pictures of surging seas during last month's storm are still circulating on the Internet. The violent waves, caused by a particularly vicious storm, played havoc along Malta's eastern shore. Watching white foaming seas smash into the land brought images of the Indian Ocean disaster to mind.

Set off by an earthquake in 2004, the giant wave had a widespread effect on groundwater of the countries hit, just as melting ice caps and rising seas are expected to do in years to come worldwide. How countries coped, or did not cope, with the tsunami's after effects may hold a lesson for the future.

Boreholes and aquifers around the shores of the Indian Ocean were contaminated after the tsunami when the sea got into the groundwater supply. All 62,000 wells in Sri Lanka were contaminated with salt water. Billions of euros were spent to rebuild homes lost in the disaster. Today some of them stand empty because no one remembered to install a rainwater collection system.

These scenes may seem very far away but they should make us think carefully about the future of this tiny island, the fragility of its fresh water resource, our expanding population and disappearing water table.

In Yemen the tsunami waters swept inland up to 400 metres, making coastal well water undrinkable. This arid country on Saudi Arabia's southern border is set to lose its ground water reserves within 10 years because of over-pumping, a problem seen also in Malta.

Chloride or salt in our groundwater is symptomatic of over-pumping. Geo-chemist and hydro-geologist Mike Edmunds predicts a briny future for vulnerable Malta. At a talk organised with the British High Commission and Bank of Valletta he said that Malta's groundwater was now under severe threat.

Proven technologies for aquifer storage and recovery, pumping clean water into the aquifer during the wet months for use in the dry season, may offer a solution.

Thirsty in summer, flooded in winter, Malta's availability of water and its need is mismatched. Rising seas due to climate change now seem a certainty over time, increasing the threat to Malta's natural supply of fresh drinking water. The pace of development and affluence has taken people away from thinking of rainwater harvesting. Architects, plumbers and the general public must re-engage with the concept of collecting water from rooftop catchment areas.

Not so long ago, in the 1970s, we were importing drinking water from Sicily. Then hundreds of boreholes were drilled, accelerating the rate of ground water taken from aquifers.

In the 1980s the water problem was shifted to electricity. Tap water is now supplied by the Water Services Corporation, at nearly a third of what it costs Enemalta to produce distilled water, for blending with sub-standard ground water until it reaches a drinkable standard.

In densely populated Malta we should look to the built environment for rainwater capture. Using rainwater means less oil burnt at the power station to produce electricity for reverse osmosis. In theory, the

Government could charge law breakers for not having mandatory systems for collection and use in place if the polluter pays principle were to be applied.

Poor maintenance and lack of planning discourage Malta's rainwater harvest in the present day. A catchment reservoir built at the airport has fallen into disrepair. Another reservoir at Corradino fell victim to roadworks when the pipes feeding it were covered with tarmac.

Stormwater is still seen as a civil protection issue rather than a resource concern. Yet, it does not make sense to collect flood water in areas like Msida when it is contaminated with sewage and too far from farmland for feasible use.

Technical guidance from the Resources and Infrastructure Ministry on minimum requirements of building regulations requires every newly constructed building to have a separate rainwater system with draw-off points for flushing toilets. The ministry is about to make a huge investment in flood control at Msida where 90 per cent of flood water comes from clean, useable runoff from rooftops.

Rainwater could be collected and used by residents during the winter months instead of causing perilous floods and sewage upwelling.

But authorities shy away from fully applying the law for every home to have a cistern. The Malta Environment and Planning Authority has merely waived the need for a notification order to build a well (historic areas prohibited) while buildings without cisterns are still permitted.

If an obligation to not only store, but also use, the captured rainwater is adopted then the prescribed cisterns need not be so large to be effective. A 25-cubic metre well can reduce household water consumption by 40 per cent. Softer than borehole water, rainwater is perfect for washing clothes.

We still flush up to one third of our drinking water supply down the toilet when rainwater would do the job with no carbon impact from power station emissions for electric-powered distillation.

Engineer Marco Cremona notes that as long as Malta remains without a water policy there can be no comprehensive plan for harvesting rainwater.