Violent weather patterns across Europe have become increasingly common with record breaking heat waves, frequent hurricanes, and cross-border storms. Over the course of the two week period from September 13th to September 27th, storm Boris poured over 125 centimeters of rain, more than two to four times the typical average of September. Numerous countries across central Europe were deeply affected by the torrential rain. Even with substantial investment in flood defense, citizens of Poland, Austria, Germany, the Czech Republic, Italy, and Romania were evacuated from their homes as flood infrastructure deteriorated. There were numerous homes, roads, and bridges destroyed and several lives lost to the conditions of the storm, along with widespread power outages and damages to transport routes. Emergency services were stretched thin due to thousands of reports, yet some flood infrastructure proved itself adequate in protecting the population.
Vienna’s Danube Canal
Prior to Boris, Vienna had invested and improved their flood management systems, and their infrastructure was able to successfully mitigate the extreme rainfall event. Their flood defense system has the capability to withstand up to 14,000 cubic meters of water. One implementation was the New Danube channel; the channel is normally closed, but is opened prior to expected floods, allowing relief to the Danube and diverting the risk of a flood. This waterway prevented flooding in 2013, where there was 11,000 cubic meters of water to withstand. Another system is the Danube Island, which was created from the material from the hollowed out channel, and acts as both flood protection and a recreational area. It also has a flood plain, which helps decrease the speed of run off water as well as storing some flood water. The combination of these two features assist in the prevention of the Danube river from flowing too quickly and over-filling. Simultaneously, Vienna has constructed a system of dykes on both banks of the Danube and reinforced and raised the existing ones, which allows for elevated water levels in preparation for extreme events. In Vienna, Storm Boris affected underground transport after the Wienfluss spilled over into the railway. Without the altercations made to the flood defense systems in Vienna, there would have been similar levels of flooding where communities were evacuated, infrastructure was destroyed, and lives were lost as other parts of Europe experienced.
Austria’s Flood Defense
The entirety of Austria has varying levels of flood defense with structures such as dykes being the most common. There have also been an increase in emergency planning in order to notify those at risk and to assist in evacuations. These take the forms of hazard zone planning, where preemptive measures are taken to communicate with those that reside in at-risk areas. Individual preparedness is a critical component in Austria’s defense, but more systematic methods include coordinated efforts of controlling river basins, dykes, and monitoring the flow of rivers by organizations. The Danube Flood Control Agency (DHK) is in charge of flood prevention for Vienna and Lower Austria. They maintain the operation of the dams, dykes, and other plants that maintain the ‘preventative and protective’ measures of the system. Upper Austria also maintains Hydraulic systems for the prevention of flooding.
Central Europe’s Challenges
The rest of Central Europe also faced similar challenges as Vienna during Storm Boris because of its heavy rainfall. For instance, Poland faced extensive flooding in the south western regions of Silesia and Lower Silesia. In Lower Silesia, 1,600 people were evacuated from Kłodzko, while in the same area a dam on the Biala Ladeckia River failed, causing destructive flooding. The lack of success within Polish infrastructure presents an alarming problem for future storms. Throughout the Boris, thousands of people faced power outages because of the systems being overwhelmed as well as damage to power cables. While the Czech Republic’s Environment Ministry labeled Storm Boris as a 1-in-50 year event, South Bohemia suffered a severe level of flooding leading to a dam bursting. This failure of infrastructure caused an exacerbation of flooding, where there were 13,500 individuals evacuated with over 600 being rescued from harm. The flood management systems of Central Europe had been seemingly upgraded for the purpose of protecting and preventing flooding; however, these systems were unable to fulfill their duties completely in the face of the unprecedented scale of Boris. Investments into large scale flood defense that are present in Poland, Austria, the Czech Republic and Central Europe are all effective during low-levels of flooding; although, there must also be more preventative measures taken for national flood defense to be effective, such as having a prepared population and an effective alert system, for there to be a strong flood defense.
Successes in Central Europe & The Path Forward
The Lower Raciborz Reservoir in Poland was a crucial component in securing the protection of Opole and Wroclaw. The reservoir was able to flatten the wave of flooding on the Oder River; with its robust ability to hold 185 million cubic meters of flood water it was able to withstand the heavy rain. In addition to this, the Polish government’s early warning system and ability to effectively declare a state of natural disaster allowed for enough time to carry out evacuations in high-risk areas. In the Czech Republic, similar early warning systems were able to prevent increased harm, and their retention basins and artificial ponds that collect storm water were able to withstand parts of the flood. Furthermore, they have begun ecosystem restoration projects to improve natural flood management. In Hungary, the government deployed thousands of individuals to work on water and disaster management. They also have 30 reservoirs with a total capacity of 721 million cubic meters, and there were 39,335 sandbags placed along areas at risk during the storm. These large scale flood defense operations were able to mitigate disaster along numerous river systems.
The various methods of flood defense were proven effective in the face of the destructive effects of Storm Boris. Yet, the torrent showed that there needs to be further resources placed in flood management in order to readily prevent and protect other locations in each country. The continued development of harsh storms internationally has put a heavy reliance on governments to strengthen and improve current systems. Simultaneously, individual awareness particularly for those located in zones prone to disaster must be enhanced, in order to streamline defense operations should disasters occur. The mechanical processes in Vienna illustrate potential methods to control the level of water throughout the Danube varying from the new channel to the construction of flood banks. The non-mechanical processes in Poland and the Czech Republic show the importance of alert systems that allow for mass evacuations for individuals in high-risk areas.
Further Questions:
- How can cities adapt to flood zones rather than changing the natural environment around it?
- Are you aware of disaster procedures in the area that you live currently?
- What are ways that natural disasters are being mitigated in areas outside of Europe?
Further Readings:
“Flood Risk Management in Austria”. Sustainability and Tourism, 2018.
“Donauhochwassershutz Wien Flood Control on the Danube, Vienna”. Stadt Wien, February 2017.
