“We are already at work to request the declaration of a national state of emergency,” Bonaccini said, adding that he had spoken to Prime Minister Giorgia Meloni about the situation.
“We will do whatever it takes to guarantee assistance and support to the people affected, for the damage and consequences of the bad weather that has hit our region,” he said.
“We have witnessed a wave of bad weather that has no historical precedent in terms of the rain that has fallen uninterruptedly in 48 hours.”
A man in his 80s drowned on Wednesday after being swept away by flood waters while riding his bicycle in Castel Bolognese, in the province of Ravenna, sources said.
The man is thought to have been riding on a road that was closed off to traffic due to the risk of flooding, the sources said.
Firefighters on Wednesday said that a dead body had been found in the rubble of a house that collapsed in Fontanelice, near Bologna, due to the extreme weather, while another person is said to be missing.
“We are particularly concerned about the (Bologna) metropolitan area,” Bologna Mayor Matteo Lepore said.
“The amount of rain that has fallen is very high, we have to be very careful.”
More than 250 people had to be evacuated from their homes in the region overnight due to the floods.
The Army has been called in to help firefighters, who conducted 400 interventions in the region overnight, and the civil-protection department in the operations.
Evacuations were carried out in the province of Ravenna, with around 100 people affected in the Faenza area, another 100 around Biancanigo di Castel Bolognese and some 60 people residing in Conselice.
Prime Minister Meloni on Wednesday expressed solidarity with the people affected by the wave of extreme weather.
In a statement, the PM said she was following the situation and was in “constant contact with the authorities”, saying she had called Civil Protection Minister Nello Musumeci, Emilia Romagna Governor Stefano Bonaccini and Civil Protection Department Chief Fabrizio Curcio.
The torrential rain caused some rivers to reach dangerous levels and rail operator FS had to suspend several services between Faenza and Forlì, Russi and Lugo, Russi and Granarolo, and Lavezzola and Mezzano.
Many more roads were closed in the provinces of Bologna and Ravenna due to flooding and landslides caused by the rain, leading to major traffic jams.
In more disappointing news, experts said intense bouts of rainfall like this will do little to alleviate the water shortage that northern Italy is experiencing after a prolonged period of low precipitation levels.
Scientists say that extreme weather events like this flooding, heat waves, supercharged storms and droughts are becoming more frequent and more intense because of climate change caused by human greenhouse-gas emissions.
For Thursday, the Civil Protection department has issued a red alert for flooding, not thunderstorms, in four areas of Emilia-Romagna: the plains of the Reno river and its tributaries, the hills of Bologna, the Romagna coast and the low hills and plains of Romagna.
There is an orange alert, again for flooding on the Secchia and Panaro plains of Modena, the Bolognese mountains, the high hills of Romagna and the Romagna mountains.
Another orange alert, but for hydrogeological risk, is in force on the central Emilian mountains, the central Emilian hills, the Bolognese hills, the Bolognese mountains, and the high hills and the mountains of Romagna.
ANSA