The theme for the 2012 World Water Day is water and food security. This theme has been chosen by the United Nations in order to raise awareness about the effects of food production on the quality and quantity of water resources.

In Malta, the production of food by the agricultural sector takes a significant toll on local freshwater resources which are primarily replenished by rainfall.

Between 2000 and 2011 the annual rainfall ranged from a low of 341.4 mm in 2001 to a high of 907.7 mm in 2003. During this 12-year period, the average annual rainfall amounted to 545.3 mm, slightly less than Malta’s rainfall climatic normal (1) of 553.1 mm per year.

Irrigation water use during two consecutive agricultural years spanning September 2008 to August 2010. In general, the volume of irrigation water used depends upon the area under irrigation and climatic factors, the most critical being rainfall. From September 2008 to August 2009 total rainfall amounted to 763.0 mm. In the following agricultural year, the total rainfall almost halved to 388.0 mm.

In contrast, the area under irrigation in 2009/2010 increased by 21.2 per cent when compared to 2008/2009. This increase, together with a decrease in rainfall, brought about a surge of 47.8 per cent in the volume of irrigation water. On average, 46.0 per cent of irrigation water is used for ‘Fresh Vegetables’, followed by ‘Potatoes’ with 29.8 per cent.

Over both agricultural years, the average irrigation water demand ranged from 374 m3 per hectare for ‘Other fruit trees’ to 18,802 m3 per hectare for ‘Flowers/Seeds’. However, it should be noted that since the land area devoted to the growing of ‘Flowers/Seeds’ is comparatively small, the irrigation water consumed by this category averaged 2.8 per cent of the total irrigation water used over both agricultural years.

From 2008 to 2011, 55.8 per cent of the public water supply produced by the Water Services Corporation originated from reverse osmosis plants. The rest, averaging 13.1 million cubic metres per year was extracted from groundwater, which constitutes Malta’s only freshwater resource. Groundwater is tapped for irrigation purposes as well.

For both agricultural years, the amount of water used for irrigation purposes exceeded groundwater extraction for public water supply. In the agricultural year 2009/2010, the amount of irrigation water used almost equalled the public water supply produced by the Water Services Corporation.

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