Turning sewage into potable water

The water was only produced to enable the Water Services Corporation to test the viability of re-using treated sewage water, which is at present disposed directly into the sea.

Around 450 tests on chemical, bacteriology and virology on different water blends produced by the experimental plant were carried out between June 2009 and March 2010, by scientists in the Water & Wastewater Laboratory.

Virology tests were also sent abroad for analysis.

Sewage water in Gozo and the north of Malta is already treated before being disposed of into the sea. But the water needs further treatment before being used for agricultural or potable purposes.

While in most countries this water is used for agriculture, in Singapore it is also blended in the potable water supply.
To further treat this water, the WSC has installed an Ultra filtration Unit and Membrane Polishing Plant at the back of the Gozo Sewage Treatment Plant.

The whole project has cost the corporation €45,000.

Following the completion of the tests in Gozo, the WSC is now in the process of transferring the equipment to Malta, where a site has been identified for further tests.

The plan is to use effluent from the San Antnin sewage treatment plant.
This will enable the corporation to test the new technology under the more adverse conditions.

The government also announced plans to decommission the Sant Antnin plant after the opening of the third sewage treatment plant in ta’ Barkat in Xghajra.

The WSC has already presented an “implementation plan” for the use of reclaimed water for the Maltese Islands, but no details of the plan were revealed, except that it includes the investment required to polish the treated sewage water.

The plan also includes the infrastructure required to set up “service points” from where users would be able to purchase the treated sewage.

Apart from conducting tests on the possible re-use of sewage water the Corporation is also investing to upgrade its RO equipment to reduce its costs.

“This besides its constant drive to minimize losses and studies on improved blending solutions,” the government spokesperson told MaltaToday.