Treene (river)

Treene (Trenen)
The Treene near Wohlde
Location
CountryGermany
StateSchleswig-Holstein
Physical characteristics
SourceBondenau
 • locationMohrkirch, Angeln
 • elevation50 m (160 ft)
2nd sourcelake Tresssee, Oeversee
 • elevation20 m (66 ft)
MouthEider
 • location
Friedrichstadt
 • coordinates
54°22′6″N 9°5′9″E / 54.36833°N 9.08583°E / 54.36833; 9.08583
Length95 km (59 mi)
Basin size797 km2 (308 sq mi)
Discharge 
 • average10.7 m3/s (380 cu ft/s)
Basin features
ProgressionEiderNorth Sea

The Treene (Danish: Trenen) is a river, hydrologically 95 km (59 mi) and nominally 73.4 km (45.6 mi) long, in Southern Schleswig in the north of Schleswig-Holstein, Germany. It is a right-bank tributary of the River Eider. It starts in northern Angeln, southeast of Flensburg, and flows mainly south-south-west before joining the Eider near Friedrichstadt.

The upper course are called Bondenau (Danish: Bondeå) and Kielsau (Danish: Kilså). Its source is situated in the ground of Mohrkirch.[1][2] The name 'Treene' begins at the Treßsee (Danish: Træsø) lake near Großsolt in the district of Schleswig-Flensburg. After about 73 km (45 mi) it reaches the town of Friedrichstadt (in Nordfriesland district).[3] There it is released through valves into the estuary of the Eider, 25 km (16 mi) above the Eider Barrage. It is the most important tributary of the River Eider. Since the construction of Kiel Canal it has been even stronger than the Eider river.