Discover the Acea Group online 2020 Sustainability Report

Water Segment

Water Segment


The scope includes the Companies Acea Ato 2, Acea Ato 5, AdF, Gori and Gesesa. Acque, Publiacqua and Umbra Acque, water Companies not included in the scope of the Consolidated Non-Financial Disclosure (pursuant to Legislative Decree no. 254/2016). They have been included only in the water graphs, with evidence of their contribution, and in a few other global data (water fed into the system and analytical calculations). Specific data concerning these Companies are provided in a separate chapter: Water Company data sheets and overseas activities.

  • Water quality
  • Sewerage service and treatment system

Our projects

Centralisation of Acea Ato 2 treatment plants

To improve the quality of treated water, Acea Ato 2 has defined a Centralisation Plan for treatment plants aimed at streamlining the treatment service, centralising treatment, where sustainable, at a limited number of sites identified through analysis of the territory from a geomorphological and urban-planning perspective.
In fact, with a high number of small and medium-sized treatment plants (127 treatment plants with capacity below 10,000 P.E.), service coverage is guaranteed primarily by large and medium-large treatment plants (42 treatment plants with capacity above 10,000 P.E.). From the date of acquisition of the Integrated Water Service (2003), 22% of treatment plants with a low capacity have already been eliminated. The reduced fragmentation in favour of medium-large plants, combined with integration of sewerage collector systems, has allowed greater control of treatment efficacy and optimisation of management and energy costs.
Acea Ato 2 has therefore prepared a rationalisation plan, which it keeps up to date, choosing between centralisation and upgrading of small plants on a case-by-case basis. The optimal solution depends on many factors that must be carefully evaluated for the specific case, in the context of assessing the entire life cycle of a treatment system. In 2020, the Centralisation Plan reached the goal of eliminating a further 7 minor treatment plants.

Experimentation of Gori on agricultural use of treatment sludge

In 2020, experimental works were carried out in the context of two university theses conducted at the Nocera Superiore treatment plant in 2019 by students of the Department of Biology and Chemistry at the University of Salerno and the Department of Biology of the Università degli Studi di Napoli Federico II in Naples, which investigated the potential agricultural use of treatment sludge produced. The treatment sludge of the plant in question, in fact, is characterised by a significant component of plant origin, derived from wastewater produced by canned/preserved food industries that contain waters used to wash tomatoes. The study compared the application of commercial compost and sludge produced at the Nocera plant, and evaluated the effects on soil quality, to verify maintenance of fertility and function. This initial verification identified that application of treatment sludge, in line with application directives regulating spreading, did not have negative ecotoxicological effects, but demonstrated very limited benefits in terms of fertility. Therefore further experimental activities to proceed with were identified, for a full understanding of the actual potential for agricultural use of sludge produced by the Nocera Superiore treatment plant.

Acea Ato 2 – Biomethane

The Acea Ato 2 project involves the creation of a biogas upgrading (refinement) section, composed of a line with selective membranes with a nominal capacity of 230 Sm3/h and a regulation and measurement unit to control the quality and amount of biomethane produced. The purpose of the project is to “isolate” the methane contained in the biogas, optimising its subsequent usage. Today, biogas is primarily used for the generation of heat for digesters. With the project underway, the methane obtained from the refinement process will instead be input into the existing gas network and destined specifically to power vehicles through appropriate "certification" of the quantities produced and input into pipes. In this way, it will be possible to access new incentives available under current legislation, ensuring the sustainability of this large investment, with a total value of € 8 million, required for performance of engineering works.
Each processing system will have a production capacity of approximately 1,300,000 Sm3 annually of biomethane, and will benefit from a significant improvement in the management of biogas produced, alongside all the other benefits from an energy, economic and environmental perspective.