The biggest water reservoirs on the mentioned rivers of multifunction character are the following:
river |
lenght³ |
river basin area¹ |
the Kłodnica (Klodnitz) |
75,3 km |
1 003,43 km² |
the Mała Panew |
131,8 km |
2 114,69 km² |
the Widawa (Weide) |
103,2 km |
1 745,90 km² |
the Barycz (Bartsch) |
133 km |
5 547,37 km² |
the Krzycki Rów |
72 km |
562,91 km² |
the Obrzyca |
65,9 km |
1 804,98 km² |
the Warta (warthe) |
808,2 km |
54 519,56 km² |
the Ina |
129,1 km |
2 150,60 km² |
the Stobrawa |
78 km |
1 586,00 km² |
The above-mentioned rivers are practically all lowland rivers. They do not cause any significant flood hazards. The largest water reservoirs on these rivers are Turawa on the Mała Panew River and Dzierzno Duże on the Kłodnica (Klodnitz).
Particularly important is the Nysa Łużycka (Lausitzer Neisse) river. The river is 251,8 km long and has a river basin of 4 403,45 km². It is a left tributary of the Odra River, into which it flows on the 542 km of the river’s run. The importance of the river comes from the fact that there are water reservoirs in tree countries: Poland, Germany and Czech Republic as well as from the river’s economic importance and all the international problems it may cause.
According to The International Odra Project, Odra's annual average runoff to the Baltic amounts to 18.5 billion m³, a value that corresponds with 29.5% of precipitation over the entire river basin.
The Odra is navigable from Kedzierzyn-Kozle (Kandrzin-Cosel) (including the Gliwice Canal that starts in the city) down the course of the river. 24 weirs are found along the distance of 186 km from Kedzierzyn-Kozle to Brzeg Dolny. This stretch of the Odra is called ‘canalized’. There is another weir under construction in Malczyce (Maltsch). Below Brzeg Dolny up to the mouth of the Warta water levels periodically preclude freight shipping navigation. The most important ports are: Gliwice (on the Gliwice Canal), Kedzierzyn-Kozle (Kandrzin-Cosel), Opole (Oppeln), Wroclaw (Breslau), Malczyce (Maltsch), Scinawa (Steinau), Glogow (Hlohow/Giogau), Nowa Sol (Neusalz an der Oder), Cigacie, Krosno Odrzanskie (Crossen an der Oder), Kostrzyn (Kostschin), and Sczecin (Stettin). Through a system of canals, the Odra has a navigable connection with Szprewa and Hawela. All reservoirs on the Odra are practically impenetrable for bi-habitat fish.
The Odra and most of its tributaries are very important ecological passageways of relatively low level of natural environment changes (in relation to the most of the EU rivers). There are seven national parks within the area of the Odra catchment. In the territory of Poland they are: Karkonosze (Karkonoski/Krkonoše/Riesengebirge), Table Mountains (Góry Stołowe/Stolové hory/ Heuscheuergebirge), Wielkopolska (Wielkopolski Park Narodowy), Drawno (Drawieński Park Narodowy), Ujscie Warty (Park Narodowy Ujście Warty) and Wolin (Woliński Park Narodowy); in the territory of Germany it is the Unteres Odertal (Dolina Dolnej Odry). Moreover, within the Odra river basin there are also landscape parks, nature preserves along with other forms of sanctuaries. Many areas, especially in river valleys, are being intended for protection within a framework of the NATURA 2000.
The Warta River (Warthe) needs to be discussed separately. Nearly half of the Odra river basin is attributed to the Warta – 54 519,56 km², which is also the Odra’s longest tributary – 808,2 km. The Warta River flows into the Odra on its 617,6 km, thus it is longer than the stretch of the Odra above the Warta’s mouth. The entire catchment area of the Warta is within the boundaries of Poland. The longest tributary of the Warta is the Notec (Netze) with the length of 388,4 km and catchment area encompassing 17 331 km². Therefore, the Notec is the second largest river – both with its length and catchment area -- within the Odra river basin (not including the Odra itself).
Other significant rivers within the Warta river basin are:
river |
lenght³ |
river basin area¹ |
the Prosna |
216,8 km |
4 916,63 km² |
the Drawa |
185,9 km |
3 290,93 km² |
the Gwda (Küddow) |
145 km |
4 947,27 km² |
the Obra |
163,8 km |
2 760,17 km² |
the Liswarta |
93 km |
1 558,94 km² |
The biggest water reservoir on the Warta is Jeziorsko. There is a navigational connection between the Odra and the Vistula (Wisła) river basins via the Bydgoszcz Canal (Kanał Bydgoski), which links the Notec with the Vistula. Most lakes of the Odra catchment along with a number of valuable natural areas are found within the Warta river basin . There are three national parks there (Wielkopolska, Drawienski, Ujście Warty) which are closely related to the water ecosystems.