CF 304: Use of Highly Polished Reclaimed Water in the Maltese Islands

The Project provides an alternative water resource to private groundwater abstraction. Three polishing plants were installed at the present Sewerage Treatment Plants and treat secondary treated sewage to very high quality standards making it suitable an safe for various non-potable purposes.

The main specific objective of the project is to produce circa seven million cubic metres of water per annum to replace part of the groundwater abstraction, thereby reducing the pressure on the water table to an environmentally sustainable abstraction level of around 24 million cubic metres per annum. In general, the Project intends to increase and diversify national water resources, increase the proportion of reclaimed water polishing, offer an alternative water supply to replace use groundwater sources for non-potable use; improve the water reuse potential in general, and mitigate the economic, social and environmental impacts of the use of traditional sources of water. The national intent to eventually stop or control/regulate private groundwater abstraction without negatively affecting the various sectors of the economy dependant on this natural water resource by offering a safe, better quality water source will benefit Malta both as a measure to improve on Malta’s groundwater reserves (quantitative and qualitative) but also will profit the Environment in the long term.

A total of 19,200 m3/day equivalent to 7M m3 per annum of reclaimed water of the highest quality will be made available to prospective users which may include also recharging of the aquifers. The quantity of polished reclaimed water will replace the present water supply arrangements. 24,000m3/day of the current 66,000m3/day sewage effluent being discharged into the sea will be further polished. This will result in a decrease of approximately 36% of treated sewage effluent from being discharged into the sea. With the production of 5.5Mm3 of HPRW spread over a nine month period equivalent to the dry period, the private groundwater abstraction is envisaged to be reduced by the same amount. The remaining wet period when the need for irrigation water in particular is limited or even zero, the remaining amount namely 1.5M m3 will be available for recharging the aquifers.