Tisza River Basin Description
The largest sub-basin of the Danube is that of one of its left-bank tributaries, the Tisza River, having a share of 19.5% in the Danube Basin and a basin size of 157.200 km2. It is located almost exactly in the geographic centre of Europe and reaches its recipient near to the town "Titel" in Yugoslavia. The considerable gap between the Tisza River’s shares in the area extension (19.5%) and in the mean total runoff (5.6%) of the Danube Basin is due to the typical lowland-character of about 25% of the Tisza Basin, lying in the Great Hungarian Plain.
The unique riparian wetland ecosystem of the Tisza Basin has to be protected and revitalized because it is seriously affected by water pollution from both point and non-point sources including serious accidents like the catastrophic cyanide spill in 2000. Furthermore severe water shortages and excessive inundations as well as devastating floods - occurring in the same year at the same place in many cases - were destroying unique species of flora and fauna.
The river basin is situated in the area of five countries: Ukraine (8,1%), Romania (46,1%), Slovakia (10,2 %), Hungary (28,6%) and Serbia & Montenegro (6,9%, formerly Yugoslavia). The total length of Tisza River is 966 km. The original length of the Tisza, with its heavily meandering river bed along its lowland stretch, from its springs in the North-eastern Carpathians (Ukraine) to its embouchure into the Danube used to be about 1,400 km around the middle of the XIXth century. During the second half of the XIXth century, very extensive measures of river training and flood control (including more than one hundred cut-offs) were taken along the river (situated at that time completely in Hungary). As a result of these works, total length of the river was significantly shortened.
The drainage basins of the tributaries of the Tisza River are rather different from each other not only in their shape, situation, size, hydrography and sloping are concerned, but also with regard to their soil composition and vegetation cover. The shape of an arching semi-circle, the towering ridge of the Carpathians (in Slovakia, Ukraine and Romania) creates the northern, eastern and southern boundary of the Tisza Catchment. The western – south-western reach of the watershed is comparatively low, in some places – on its Hungarian and Yugoslavian reach, situated between the here practically parallel courses of Danube and Tisza – it is in fact even.
Traditionally, based on the hydrogeographical characteristics, the Tisza River basin is divided into three main parts: the mountainous Upper Tisza in the Ukraine (upstream from the Ukrainian/Hungarian border), the Middle Tisza in Hungary, receiving the largest tributaries: the Bodrog River collecting the waters of the Carpathians in Slovakia and the Ukraine as well as the Someş/Szamos and Mureş/Maros, both draining the Transylvanian Basin in Romania) and the Lower Tisza (downstream to the Hungarian/Yugoslavian border).
Some sections of the main stream of Tisza River create the state borders (Romania-Ukraine, Ukraine-Hungary, Ukraine-Slovakia).
Shmu, Vuvh, Vituki, Icim (2003, unpublished): Final Report of Workpackage 3: "Identification of environmental and water management issues", 73 pp.