In 2017, the Hera Group operated the sewage and wastewater treatment service in 231 municipalities, 49 of which as Marche Multiservizi and 18 of which as AcegasApsAmga.
At Group level, the sewage service for all urban areas covered 93% of the requirements of the areas served (population equivalents). This value rises to 99% if we consider only urban areas with over 2,000 population equivalents in Emilia-Romagna.
In 2017, the treatment service covered 92% of population equivalents in the areas served by the Group. This value rises to 99% if we only consider urban areas with over 2,000 population equivalents in Emilia-Romagna.
These values are very positive if compared with the average of the Italian utilities that were included in the Utilitatis study in 2016, at 90% for the sewage network and 88% for the treatment network. Concerning the country-wide values, the latest data available are for 2007, when 85% of Italians was served by the sewage network and 70% by a treatment plant. (Source: 2009 Utilitatis Blue Book for 2007). Assessing the percentage of wastewater treated compared to the total, the Italian average in 2015 was 89.9%, with negative peaks for the regions of southern Italy such as 68.5% in Sicily or 76.9% in Calabria (source: ISPRA).
The Hera Group treated over 364 million m3 of wastewater in 2017, compared to 393 million in 2016 as a result of the low rainfall in 2017 and, therefore, of the lower inflow of rainwater. The sewer networks that feed those plants are generally mixed-type systems, and the volumes treated therefore depend on rainfall. In Emilia-Romagna, wastewater treatment was carried out in 880 plants, 14 of which have a capacity of over 100,000 population equivalents each.
The sewage network Hera Spa operates is approximately 14,681 km long and about 53% of the total (55% in 2014) is a mixed-type system. The Group’s sewage network is approximately 18,642 kilometres long, and about 58% of the total is a mixed type system.
The indicator relates to the plants with over 10,000 population equivalents (the volumes treated in these plants are 77% of the total wastewater treated) and is calculated on the basis of the ratio between the concentration measured for BOD5, COD, TSS, ammoniacal nitrogen, phosphorus and total nitrogen and the related maximum concentrations permitted by Legislative Decree 152/2006.
The efficiency in removing pollutants to comply with the regulatory limits, as expressed by the indicator in the chart, is related to the treatment capacity of the plant and the technologies used. At Group level, this indicator averages 39% of regulatory limits, taking into account BOD5, COD, TSS, ammoniacal nitrogen, phosphorus and total nitrogen, and 30% excluding phosphorus and total nitrogen. The indicator that expresses the efficiency of removal of the main pollutants improved slightly compared to previous years, also due to the fact that some important upgrade projects started in previous years are nearing completion.