The area of Italian territory classified as at risk of landslides has increased by 15% according to the Hydrogeological Structure Plans (PAI), rising from 55,400 km² in 2021 to 69,500 km² in 2024 — equivalent to 23% of the national territory. This is according to the fourth ISPRA Report on “Hydrogeological Instability in Italy” – 2024 Edition.
The most significant increases are recorded in the Autonomous Province of Bolzano (+61.2%), Tuscany (+52.8%), Sardinia (+29.4%), and Sicily (+20.2%), mainly thanks to more detailed studies carried out by district basin authorities and autonomous provinces. Areas of higher hazard (classified as P3 and P4) have grown from 8.7% to 9.5% of the territory, while 94.5% of Italian municipalities are now at risk of landslides, flooding, coastal erosion, or avalanches.
Extreme events and climate change
The 2022–2024 period has been marked by exceptional hydro-meteorological events: from widespread flooding in the Marche region in September 2022, to rapid mudflows in Ischia in November 2022 that caused 12 deaths, to the floods in Emilia-Romagna in May 2023 with damages estimated at €8.6 billion, and intense rainfall in the Aosta Valley and Piedmont in June 2024. Climate change is increasing the frequency of intense, short-duration rainfall, directly contributing to more frequent shallow landslides, rapid mudflows, and sudden floods, even in areas historically considered less vulnerable.
Landslides and population at risk
With over 636,000 recorded landslides, Italy remains one of the most landslide-prone countries in Europe. Approximately 28% of these events are rapid in nature and have high destructive potential, often with severe consequences. In 2024, nearly 6 million Italians live in landslide risk areas, with 1.28 million residing in the highest hazard zones (P3 and P4). At risk are more than 742,000 buildings, nearly 75,000 business units, and 14,000 cultural heritage assets.
Floods and future updates
The report previews the upcoming update to flood hazard and risk maps, scheduled for 2026, as part of the third management cycle of the Floods Directive (2022–2027).
Coastal erosion: positive signs
On the Italian coast, erosion is showing signs of reversal. Between 2006 and 2020, over 1,890 km of beaches experienced significant changes, representing 23% of the national coastline. Advancing stretches (+965 km) now exceed those affected by erosion (+934 km), highlighting the effectiveness of beach nourishment and coastal protection measures.
Avalanches and mountain areas
Avalanche-prone areas now cover 9,283 km², representing 13.8% of mountainous territory above 800 metres. For the first time, ISPRA has produced a harmonised national avalanche mapping with the support of AINEVA, the Carabinieri's Meteomont Service, and the Regions.
Technology and prevention
To support prevention and intervention policies, ISPRA manages the open data platform IdroGEO and the National Database of Funded Soil Protection Projects (ReNDiS), which records nearly 26,000 interventions over the past 25 years, totalling €19.2 billion. Furthermore, IdroGEO’s new virtual assistant, based on Artificial Intelligence, allows users to interactively consult maps and information on hydrogeological instability.
