Since the devastating floods of August 2002, the Prague municipality has invested four billion crowns in the city’s flood protection.
Some 20 kilometers of barriers have been built, along with flood gates, and a pumping station. Modifications to rivers and streams in the region have also taken place, returning previously straightened streams to their original beds. Moreover, a new flood wall could protect the Prague Zoo from flooding in the future.
The flood, which happened 20 years ago on August 12-15, damaged, among other things, almost two dozen stations of the Prague metro. In total, the flood caused 27 billion crowns in damage in Prague alone, and destroyed dozens of houses. Over 50,000 residents had to be evacuated.
The city’s anti-flood measures now include earthen embankments, solid concrete walls and aluminum mobile barriers. The total length of the protection is 19.26 kilometers. Of this, 6.8 kilometers of mobile embankment is made up and its height is from 0.2 to 6.27 meters. Walls are built beneath all barriers, all the way down to the impermeable subsoil, which in some places is up to 12 meters deep.
In addition to the barriers along the Vltava, a station with six pumps has been built at Rokytka. The city also built an anti-flood closure for the ports and the tributary of the river. The station makes it possible to close the mouth of the Rokytka and divert water into the Vltava instead. Above the gate, footbridges for pedestrians and cyclists lead from Thomayer’s orchards to Libeňský ostrov. They are eight meters above the 2002 water level, which remains the highest ever recorded.
The Čertovka barrier has also been built in the center of the city. “It’s a 51-ton underground gate that’s 23.5 meters long and 4.9 meters high,” Hofman said. According to the city, it is also possible to add mobile barriers to the gate, and thus to create an overall fence with a height of 7.87 meters. Gas stations and barriers were also created in the south of the city.
According to Hofman, anti-flood measures also include the revitalization of streams and rivers. In the past, their riverbeds were straightened and lined with concrete, which, by changing the natural course, made it more likely for the overflow to threaten people and their houses.
The municipality is also expanding flood protection measures in Zbraslav and extending it between the Old Town and the New Town. In Radotín, the expansion of protection in Vrážská street continues.
According to the spokesman, the protection of Lahovice, Lahoviček and Sedlce still remains a problem. “The area of the confluence of the Litovicko-Šárecký stream with the Vltava in V Podbabě Street is also a problem. It concerns 35 endangered properties, the Břetislavka residence and the adjacent inn,” added Hofman.
A new flood wall could protect the vulnerable Prague Zoo from flooding in the future. According to the current proposal of the Prague Institute of Planning and Development (IPR), it should be created roughly in the places where the garden is now bordered by a fence in its lower part.
The floods in 2002 and 2013 caused great material damage to the zoo and caused the death of several beloved animals. Since then, though, the hippo and elephant exhibits have been moved out of the possible flood zone. The zoo now protects the embankment against high water. Pavilions of animals that are difficult to evacuate have also been moved to a new location outside the flood
zone. The project could be approved this summer.
The floods in August 2002 affected almost all of Bohemia. 17 people lost their lives. These measures will, ideally, prevent such a catastrophe from ever happening again.