South Morava

South Morava (Serbian and Macedonian: Јужна Морава, Južna Morava) is a river in the Republic of Macedonia and Serbia which represents the shorter headwater of Great Morava. from 10th to 19th century, South Morava was known by the name Bulgarian Morava (from its Bulgarian name: Българска Морава, Balgarska Morava). Today, it is 295 km long, flowing generally in the south to north direction, from Macedonian border through Kosovo to Central Serbia, where it meets West Morava at Stalać, to create Great Morava.

Source
It begins in the mountain of Skopska Crna Gora, in Republic of Macedonia, north of its capital Skopje. Streams of Ključevska reka and Slatinska reka join together to form the river Golema, which, after passing the Macedonian-Serbian border, is known as Binačka Morava. After 49 km it meets Preševska Moravica at Bujanovac, and for the remaining of 246 km flows as South Morava.

Geography
River belongs to the Black Sea drainage basin, and its own drainage area is 15,469 km², out of which 1,237 is in Bulgaria (through its right tributary Nišava). Its average discharge at the mouth is 100 m³/s and it is not navigable.

South Morava has a composite valley, which means it consists of series of gorges and depressions in this order: Gnjilane depression-Končulj gorge-Vranje depression-Grdelica gorge-Leskovac depression-Niš depression-Aleksinac depression-Stalać gorge. After breaking through the last, Stalać gorge, it meets West Morava.



In macro-geological point of view, South Morava connects Aegean basin with Pannonian basin. This creates a phenomenon named apparent flow inversion, because it seems that river from one lowland climbs up the mountains and then flows into another lowland. The point connecting these two large geological basins is Grdelica gorge (Serbian: Grdelička klisura/Грделичка клисура), but the bottom of the gorge, where river flows, is much lower than the mountains surrounding it, so river flows normally.

South Morava used to be 318 km long and represented longer and natural (flowing in the same direction) headwater of Great Morava. Causing severe floods in history, meandering river has been shortened by almost 30 km until today, so it became shorter than West Morava. However, West Morava always had bigger discharge.

Areas in southern Serbia where South Morava flows have been almost completely deforested which causes one of the most severe cases of excessive erosion in the Balkans. As a result of this, river brings large amount of materials to Great Morava, filling and elevating its river bed, which helps the huge floods of its daughter river.

Tributaries
South Morava has 157 tributaries. Most important left ones are: Jablanica, Veternica, Pusta reka and Toplica. Right tributaries are: Vrla, Vlasina, Nišava (the longest) and Sokobanjska Moravica.

Economy
It has significant potential for electricity production, but this has not been used at all. Huge hydroelectrical system has been constructed in its drainage basin, though (Vlasina- Vrla I-IV power stations).

To a certain extent, its waters are used for irrigation.

The most important role river valley has in transportation. It's the natural route for both railway and highway Belgrade-Skopje-Thessaloniki.