From Severe Drought to Severe Flood: Italy Hit Hard by Extremes
Daniel BernetJune 19, 2023
After severe drought conditions in Italy which can be traced back over the last two years, and the country recording its hottest year in 2022, severe rainfall events this May added yet another climatic extreme.
Two separate severe rainfall events struck the Emilia-Romagna region (pop. ~4.4 million) in the north of Italy in just two weeks.
Italy’s longest river, the River Po, defines the Emilia-Romagna region’s northern border, measuring some 290 kilometers (180 miles) from its northwest corner, located around 30 kilometers (20 miles) south of Milan, through to its southeast corner with the city of Rimini and the Republic of San Marino on the Adriatic Coast.
The region's capital, the historical city of Bologna (pop. ~390,000) was not spared from the severe flooding.
May 2-3 Rainfall Event
The first rainfall event happened between May 2-3, with an area of low pressure centered over central Italy producing localized thunderstorms and prolonged rainfall for around 36 hours, with Ravenna province being the most impacted. The floods caused two casualties.
The 652-kilometer-long (405 miles) River Po, which has its source from the melting snow waters and precipitation in the Alps, had suffered from low water levels since the previous summer. The severe rainfall between May 2-3 raised the level of the Po by 1.5 meters (nearly 60 inches) in 24 hours and smaller rivers in Emilia-Romagna overflowed their banks.
With the heavy rainfall, the region’s capacity to absorb additional water without spilling it onto the floodplains decreased significantly. This set the stage for more intense flooding in the weeks thereafter.
Between May 15-17, a storm named Minerva remained broadly stationary in the Mediterranean Sea and brought prolonged and intense rainfall on pre-saturated soils that led to widespread flash and river flooding, as well as hundreds of landslides across the Emilia-Romagna region, and parts of Marche and Tuscany.
In parts of the region, an average of 200 millimeters (8 inches) of rain fell within just 36 hours, and in the eastern provinces of Forlì, Cesena, and Ravenna, the rainfall equivalent of around half the average annual total for this region fell in 36 hours, with some 500 millimeters (20 inches) of rain.
Fifteen people were killed, around 36,000 people were evacuated, and thousands of rescues were carried out by emergency services as the floodwaters inundated dozens of towns and villages across over 100 municipalities in the four eastern provinces of Ravenna, Forlì-Cesena, Bologna, and Rimini.
Assessing the Damage
After the rainfall stopped and the extent of the damages started to emerge, Stefano Bonaccini, President of the Emilia-Romagna region pegged the economic loss at a few billion euros including transport infrastructure damages at more than €700 million.
Disruption was widespread. Over 600 roads had to be closed, 50,000 households were without power at its peak, and the Formula One Emilia-Romagna Grand Prix at Imola on May 19–21, was canceled due to safety concerns.
105 school complexes have been damaged, and approximately 5,000 farms have been affected including thousands of farm animals that are also thought to have been killed.
Ravenna Province saw the greatest impact. With a population of just under 400,000, according to local media reports, at least 3,000 homes were flooded.
Across the four provinces, at least 23 rivers burst their banks, with reports of some 400 landslides, together with the emergence of sinkholes, bridge collapses, and vehicles being washed away.
Emilia-Romagna Experiences Extremes
From one extreme to another, the Emilia-Romagna region went from severe drought to severe flood with an event that ranks as the worst flooding that this region has experienced in decades.
With the most affected region being low-lying and predominantly flat, and with many river embankments breached, the stagnant water takes more time to recess – increasing the damage to properties, with the clean-up and repair becoming delayed, and being more complex, and more time-consuming.
As part of Moody's RMS comprehensive Event Response service, alongside event reports during and after the event, a detailed flood hazard footprint was produced within 7-14 days following the peak event, providing our clients with the ability to analyze the extent and potential impact from this flood event.
The footprints show how the heavy rainfall concentrated across the Apennine Mountains in the south triggered flooding in the many headwaters of the smaller rivers that have their source in this mountain range.
The floodwaters traveled downriver, causing devastation along the way, and spilling the excess water onto the flat, low-lying land in the north, causing extensive and widespread flooding in the most-populated areas, together with concentrations of commercial, industrial, and agricultural areas.
It will take time until we have a clear picture of the flood event’s economic damage, but it is already obvious that the largest portions of the damages are not covered by any flood insurance.
In particular, natural catastrophe insurance take-up for homeowners and residents, including flood coverage, is low.
According to the Associazione Nazionale fra le Imprese Assicuratrici (ANIA), the region’s take-up rates are roughly in line with the country average of 4.9 percent, ranging from one percent to eight percent across the region.
Businesses and industrial facilities are more likely to get some recovery from flood insurance but this will vary significantly based on the nature and size of the business.
For example, the ANIA reports flood insurance take-up of approximately three percent for micro-businesses (fewer than 10 employees) across all of Italy, putting this class largely in line with residential take-up rates.
On the other hand, reportedly over 90 percent of large businesses (250 or more employees) are insured for flood. Due to this pronounced protection gap, residents, local and federal governments, SMEs, and corporates will have to shoulder the larger portion of the economic losses from this event.
Building Resilience Against Extreme Flood Events
As the full extent of the damage slowly emerges, the question of how to better cope with similar future events needs to be addressed.
Although according to an early attribution study (Barns et al., 2023), climate change may not have an effect on the occurrence frequency of such severe precipitation in the region during the spring season.
Climate change is expected to lead to wetter conditions in the fall and winter, with an overall increase in flood risk in Italy, as indicated in a recent Moody's RMS whitepaper entitled 'Modeling Future European Flood Risk' (clients can access the whitepaper via Support Center here).
With an expected increase in risk, there is an even greater need to become more resilient against flooding and in general against natural catastrophes. Both the local Italian and international insurance markets can play an important role to help close this protection gap.
Indeed, while a large portion of Italy is exposed to floods, severe convective storms, and earthquake risks, the country also offers a great opportunity for risk diversification across Europe, a role the reinsurance industry can take to diversify risk globally. This can further help a country to deploy capital more efficiently and, hence, become more resilient.
The pre-condition for any such market-growth initiative is a sound understanding of the risk – both today and in the future.
With over 20 years of experience in flood modeling, Moody’s RMS has made great strides to help understand and manage flood risk around the globe. Risk modeling solutions are available as probabilistic models (catastrophe models) and/or as underwriting data sets (hazard mapping, hazard lookups, risk scoring, loss cost pricing, etc.).
To take the necessary steps and start to close the protection gap, and increase resilience for businesses and residents alike, our Moody's RMS flood risk model suites, such as our Europe Inland Flood HD Models cover 14 countries across Europe.
As a longstanding partner to the industry, Moody's RMS provides all the tools needed to help insurance companies, (re)insurers, and brokers, but also agencies, governmental bodies, and regulators to better understand the flood risk that their communities face.
And as flood risk is not the only peril for which Italy needs to become more resilient, Moody’s RMS provides state-of-the-art risk modeling tools for severe convective storms (hail, straight-line wind, tornado) and earthquakes.
To find out more about Moody’s RMS Europe Inland Flood HD Model click here, and for risk modeling and risk management data solutions for Europe, click here.
As a senior product manager, Daniel is responsible for the Europe and Southeast Asia Inland Flood Models. He has been with RMS for more than 3 years, joining RMS after conducting doctoral and postdoctoral research at the Mobiliar Lab for Natural Risks, University of Bern, focusing on the occurrence and modeling of surface water flooding.
Prior to academia, he was working for a small Swiss NGO managing different water-related projects in Nepal, following the conclusion of a bachelor's and master's degree in Environmental Engineering at the Swiss Federal Institute of Technology ETH Zurich.