The Dyje, known in German as the Thaya, is a river in South Moravia and Lower Austria that is comparable in length to the Morava. According to Povodí Moravy, s. p., it measures 311 kilometres to its sources, including the section on Austrian territory. It is the second most important watercourse in the Morava basin. [1]
Source area
In its source area the Dyje has two branches, the Austrian and the Moravian. The Austrian Thaya (Deutsche Thaya) rises near the municipality of Schweiggers in Lower Austria and has the longer course, the larger catchment area and the greater discharge. In the Czech Republic, however, the Moravian Thaya is regarded as the main branch; it rises near Panenské Rozsíčko at an altitude of 657 metres above sea level. It joins the Austrian Thaya on Austrian territory near the municipality of Raabs and returns to the Czech Republic below the municipality of Podhradí. [1]
Course
In the upper part of the river lies the Vranov Reservoir, one of the largest valley reservoirs in the whole Morava basin. Further on, the Dyje meanders in a steep wooded valley within Podyjí National Park. Below Znojmo it enters the flat Dyje–Svratka Valley. In this lowland, the Dyje meets its largest tributaries, the Svratka and the Jihlava, in the area of the middle reservoir of the Nové Mlýny waterworks. The lower course flows through Břeclav and joins the Morava below Lanžhot. The confluence of the two rivers lies at an altitude of 148 metres above sea level, and the total absolute fall of the Dyje is 506 metres. [1]
Svratka
The largest left-bank tributary of the Dyje is the Svratka. It rises north of Žďár nad Sázavou near the village of Cikháj on the southwestern slope of Žákova hora at an altitude of 823 metres above sea level. At first it flows northeast toward the village of Borovnice, then southeast toward Brno. As far as Veverská Bítýška it mostly runs through a narrow valley with high slopes, where the valley floor does not exceed a width of a few hundred metres. Below Brno it enters the lowland of the Dyje–Svratka Valley. The catchment area of the Svratka at its mouth in the Dyje is 4,115 km². [1]
Two significant reservoirs stand on the Svratka, the Vír and Brno reservoirs. In recent years water managers have been dealing with pollution of the river by phosphorus, which causes eutrophication of the water in both reservoirs. [1]
Chronology
- — Conservationists released about 2,100 sturgeons into the Morava and the Dyje. → Ekolist.cz ČTK / České noviny