Water supply networks: more than 42 litres out of every 100 do not reach the taps from the mains
The solutions work, as a report by SHIFT points out, but following the NRRP, it is necessary to improve the indicators and set up a permanent working group
For every hundred litres fed into Italy’s water mains, more than forty-two do not reach the taps. This is the average for 2024 recorded by ARERA – 42.5 per cent – with peaks of 50.6 per cent in the South and on the islands. The tools to reduce this wastage do exist, ranging from sensors that ‘listen’ to the noise in the pipes to digital models of the network. What is missing, according to the document “From emergency management to resilience: technologies to understand, protect and manage the resource” drawn up by the “Aquatech” working group of SHIFT, an Italian climate policy think tank, are the conditions necessary for them to work on a large scale. Three key issues have been identified: regulations that do not yet recognise the value of the data, declining funding following the National Recovery and Resilience Plan (PNRR), and overly fragmented service management.
The paradox of spending
According to the report, ‘reducing water losses is a priority over relying on new sources and infrastructure’, in line with the European strategy that prioritises efficiency over increasing supply. Yet, of the 29.6 billion in investment planned by operators for 2024–2029, 7.95 is allocated to tackling leaks, and of this, 75.69 per cent is spent on replacing and rehabilitating pipes, whilst only 18.84 per cent funds metering, district management, remote monitoring and information systems. At a renewal rate of 0.7 per cent of the network per year, it would take over a century to replace the entire network, whilst managing pressure, actively detecting leaks and monitoring districts costs, on average, around one-tenth of the cost of replacement per cubic metre recovered. The most advanced initiatives, the report notes, begin with metering and the division of the network into districts. In the province of Brescia, for example, four districts equipped with self-powered sensors have enabled a reduction in losses of around 22 per cent.
Rules: measure carefully
The first area for action concerns indicators. The percentage indicator is not recommended by the leading international technical bodies or by European guidelines, precisely because losses are diluted within consumption figures. In the case of Italia, where per capita consumption is roughly double that of Northern Europe, the same loss in volume carries much less weight in percentage terms; were consumption levels to be brought into line with those of Northern Europe, the national figure would rise significantly. Furthermore, the percentage tends to favour large cities, where consumption is concentrated, and to penalise operators in rural areas with long networks and few inhabitants.
SHIFT proposes placing greater emphasis on the cubic metres lost per kilometre of network and supplementing this with the Infrastructure Loss Index (ILI), which compares a network’s losses with the technically achievable minimum. Targets should be set according to each operator’s starting point, and ARERA’s Class A should not be viewed as an end in itself: the 12 cubic metres per kilometre per day that define it are high compared to the one or two cubic metres recorded by Dutch and Danish operators. It is also a way of preparing for the European deadline: by 12 January 2028, the Commission will set a loss threshold, and Member States that exceed it will have two years to submit an action plan.
The second issue is data quality. The authority awards bonuses and imposes penalties based on the figures declared by the operators, without any technical validation of the water balance, and in the 2022–2023 period, 40 per cent of the operators examined had incomplete or inconsistent data or documentation. The proposal is to reserve bonuses for those who submit a water balance validated by a party other than the one who drew it up, with the status of ‘validator’ following the American model and drawing on the example of the certification scheme for leak detection technicians launched by the Italian Association for Non-Destructive Testing, which has already certified over 150 operators. The system should be trialled in a pilot area.
