Answer given by Mr Sinkevičius on behalf of the European Commission
The Habitats Directive requires the Member States to take appropriate steps to avoid the deterioration of the habitat types and the significant disturbance of the species for which Natura 2000 sites have been designated. The lack of minimum ecological water flow may lead to a breach of these obligations. The Commission has issued guidance on how Natura 2000 sites should be protected and managed, including a specific guidance on hydropower on how it could operate in accordance with the requirements of EU Nature legislation.
The Water Framework Directive (WFD) requires Member States to ensure good status of all water bodies. This includes in particular the obligation to ensure a minimum ecological flow for aquatic ecosystems and to adapt the operation of hydropower plants to this requirement. It is under Member States’ responsibility to define values for ecological flow in all water bodies and to implement appropriate measures to achieve it, including through the obligation to control water abstraction and impoundment. Guidance on ecological flows is at the disposal of Member States. In the follow-up to the Commission report on the second River Basin Management Plans, Italy informed the Commission of a 2017 technical guideline on methods to determine minimum flow. These should be implemented by all River Basin competent authorities, including Sicily.
Without prejudice to the Commission’s powers as guardian of the Treaties, Member States are primarily responsible to ensure compliance with EU legislation. It is for the relevant authorities in the Member States to impose measures or restrictions of water uses to the relevant companies to ensure that they operate in a way that is in line with environmental legislation.
-  Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora, OJ L 206, 22.7.1992, p. 7‐50.
-  https://ec.europa.eu/environment/nature/natura2000/management/guidance_en.htm
-  https://eur-lex.europa.eu/legal-content/EN/TXT/?qid=1542188309010&uri=CELEX:52018XC0618(01)
-  Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy, OJ L 327, 22.12.2000, p. 1‐73.
-  https://ec.europa.eu/environment/water/water-framework/facts_figures/guidance_docs_en.htm
-  https://ec.europa.eu/environment/water/water-framework/impl_reports.htm
-  Decreti | Ministero della Transizione Ecologica (mite.gov.it)
-  In this case, the Autorità di Bacino del Distretto Idrografico della Sicilia: firstname.lastname@example.org