Sava River

Sava River is the third longest and the largest by discharge tributary of the Danube River. The Sava River is formed by two mountainous streams: the Sava Dolinka (left) and the Sava Bohinjka (right). From the confluence of these headwaters the Sava River is 945 km long. Together with its longer headwater, the Sava Dolinka River, in the north-west, it measures 990 km. It flows through in a NW-SE direction through Slovenia, Croatia, Bosnia and Herzegovina and Serbia. In one part it forms the border between Slovenia and Croatia, then between Croatia and Bosnia and Herzegovina, as well as between Bosnia and Herzegovina and Serbia.

Figure: Schematic longitudinal profiles of the Sava River and some of its main tributaries


There is a common understanding that the course of the river can be divided into 3 sections:
 
  • Upper Sava, between the confluence of Sava Dolinka and Sava Bohinjka and Rugvica (rkm 658, measured from the Sava River mouth). The catchment area of the Upper Sava comprises mountainous and hilly relief
  • Middle Sava, between Rugvica and the mouth of the Drina River (km 178) is a lowland,alluvial section, characterized by wide floodplains, and mouths of numerous tributaries
  • Lower Sava, downstream of the mouth of the Drina River, is also alluvial section. There are no significant tributaries on this section. The most downstream, 100 km long section is under the influence of the Danube

Common feature of almost all right tributaries of the Sava River is their torrential behavior, particularly in their upper sections while left tributaries (except in Slovenia) drain mostly flat areas and low hills of the Pannonian basin. The slopes and flow velocities of the left tributaries are smaller and the streams are meandering.