Malta represents the water supply challenge confronting many countries in the Mediterranean region. Although its population has an abundant, affordable and reliable supply of safe drinking water, its aquifers are under pressure from over-abstraction, seawater intrusion and pollution from both urban and agricultural sources. As the population becomes more affluent, the pressures on water quality and availability increase. Desalination technology could supply all of Malta’s drinking water needs, but being an energy-hungry option in a country dependent on imported oil, it would be neither economically nor environmentally sustainable. The current water challenges in Malta can be solved through innovation, regulation, good governance and cooperation. If achieved, it will be a model for water management.
Malta is essentially an aquifer (a rock containing usable water) made mostly of limestone (a common aquifer rock holding water in interconnected fractures and cracks), which originally formed on the ocean bed some 25 million years ago. The discovery of fossils from animals originating in North Africa and Europe is evidence that geological force formed a land bridge between both continents some 10 million years ago. During ice ages, the sea level dropped and then rose again as the ice caps receded. Following the end of the most recent ice age, around 12,000 years ago, the sea rose again leaving the islands of Malta and Gozo isolated.
Malta has two main aquifers. The larger and deeper “sea-level aquifer” forms a solid foundation and provides the largest source of groundwater supply. It reaches the surface in some places (“outcrops”) where rainfall can directly infiltrate and replenish the aquifer. In other areas, it is covered by clay, on which lies another limestone unit (“the upper limestone”).