 Satellite picture of Croatia affected by the storm system of 24–25 July 2020 | |
| Date | 24–25 July 2020 |
|---|---|
| Location | Zagreb, Croatia |
| Cause | Heavy rain, combined sewer system failure |
| Deaths | 1 |
On the night of 24–25 July 2020, after 21:00 local time (CEST, 19:00 UTC), Zagreb, Croatia, was struck by a storm which produced one of the worst flash floods in the city's history. An episode of intense rainfall dumped more than 50 millimetres (2 in) of rain within two hours. The torrential streams of the mountain overlying Zagreb surged and overwhelmed the city's combined sewer system, causing flooding. The effects were worst felt in the inner city, notably Ilica, Donji grad, and Trnje, though many suburbs were also affected, including Buzin, Črnomerec, Jankomir, and Maksimir. Public transport and automobile traffic ceased in many streets, while trapped people had to be rescued from flooded cars and apartments. A firefighter died at an intervention. No financial estimate of damages was released by the authorities. The city government reported receiving over 2,000 damage claims during an eight-day filing period.
Zagreb lies on the foothills of Medvednica mountain, with the inner city squeezed on a floodplain between the mountain and the River Sava. Both the mountain streams and the river have produced deadly floods in the past. A system of flood defences has since been created to prevent flooding, and is under the jurisdiction of the state water management company, Hrvatske vode. However, in spite of flash flood hazard warnings issued by Croatian and international agencies in the preceding 48 hours, the flood defences were not activated. A group of Trnje residents broke into the empty building of the Kuniščak dam, which functions as the outlet to many of the torrential streams, and opened the dam to drain the flood waters from the city. In the following days, a controversy ensued about who was responsible for the dam being closed, and its control building locked and unstaffed. Hrvatske vode, the mayor, and the city's water and sewer utility company all denied responsibility for the flood and faced criticism from the public. Additionally, a local man broke in and operated the dam controls was arrested by the police in an incident described by some as a case of police brutality, prompting a public outcry. Hrvatske vode filed a police complaint for breaking and entering against the group of residents. The man was exonerated of all charges in May 2021.