The Wrocław Floodway System was realized after the 1903-Flood, in the period 1905–1922. It had the maximal discharge capacity equal about 2300 m³ · s^–1. As important elements of this System can be qualified the polders (inundation fields) Lipki–Oława, Bliżanowice–Trestno and Oławka. A catastrophic flood appeared in 1997, with maximal discharge equal 3530 m³ · s^–1 in the Odra gauging station Brzeg Most. This flood caused the inundation of a great part of the town Wrocław, the destruction or damage of many hydrotechnic and land reclamation structures as well of bridges and embankments. The intake weir to the dumping canal Odra–Widawa was destroyed also. Many projects were realized after the 1997-Flood, concerning the modernization of the Wrocław Hydrotechnic System. The main solution was presented in the frame of the Feasibility Study for the flood reservoir Racibórz on the river Odra and the modernization of Wrocław Hydrotechnic System (2004). The design probable flows are equal 3100 m³ · s^–1 for the 1000-year flood and 1850 m³ · s^–1 for the 200-year flood. Actually the Odra River Flood Protection Project is elaborated, being the continuation of the Feasibility Study. A great flood appeared in May and July 2010 in the watershed of Odra river, with maximal discharges about 2100–2200 m³ · s^–1 in the entrance to the Wrocław Floodway System. The maximal discharges in 2010 were a little smaller than in 1903 and a little higher than in 1930. For the protection of the town Wrocław, one has decided to inundate the 3 cited polders and drop a part of Odra flood discharge to the river Widawa. The damages caused by this flood were smaller than in 1997. City quarter Kozanów was inundated once more. Some embankments were damaged, for ex. the dam of the polder Lipki–Oława. The high stages appeared especially in the Odra river upstream of Wrocław. The maximal stages in the gauging stations Brzeg Most and Oława in 2010 were comparable to the maximal values in 1997, despite of much lower maximal discharges. This phenomenon was caused by the decrease of potential discharge of the river, mainly by river bed sedimentation and by development of vegetation.

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