Non-registration of water pumped into rooftop tanks is expected to be more than halved after all the water meters are changed, a conference heard yesterday.
No less than 18 per cent of water in rooftop tanks is currently undetected and therefore uncharged.
The figure is expected to be brought down to seven per cent, Ronald Pace from the Water Services Corporation told a conference on the subject.
The small trickles of water into the tank when it is filling up go undetected by the water meter, with the corporation dismissing it as “unavoidable”.
The conference was organised as part of the corporation’s 20th anniversary and brought together local and foreign experts to discuss non-revenue water – water produced or fed by the corporation into the system but which is not paid for by the consumer.
Mr Pace, who is responsible for dealing with such leakages as well as the roll-out of the Automated Metering Management project, said 56,000 meters have been installed so far – more than 50 per cent of the total.
All meters installed before 2003 will be changed, bringing down the average age of the meters from 9.2 years to around six years.
He said the new meters will go a long way towards reducing the amount of undetected water although even brand new meters were failing to detect such low flows.
Asked whether this could ever be solved, Stephen Galea St John, responsible for leakage management, said rooftop tanks, although unnecessary because the level of service has improved considerably, seem to be there to stay.
“There are other methods of decreasing the water losses by installing a device inside the actual tank but this has to be done at the mercy of customers so we are not seeing it as a possible solution,” he said.
Mr Galea St John said the demand of 160,000 cubic metres of water per day in the 1990s had halved, despite an increase in population.
The corporation supplies water through 90 boreholes in Malta and 30 in Gozo, 10 pumping stations in Malta and two in Gozo and three reverse osmosis plants which are not run at their full capacity. A total of 45 per cent of the water is supplied through boreholes with the rest supplied by reverse osmosis plants.
The new meters will result in more frequent and accurate billing and a substantial decrease in water which is not billed.
Factors of ‘no revenue water’ include theft, although this was limited, and meter reading and billing mistakes.
The new meters transmit data remotely every four hours, enabling the corporation to detect a problem when variations between consumption and supply varied considerably.