Or (Rhume)

	Or
	Southwestern Harz with Oder
	Data
Water code	DE : 48826
location	District of Goslar , District of Göttingen , District of Northeim , Lower Saxony ( Germany )
River system	Weser
Drain over	Rhume → Leine → Aller → Weser → North Sea
source	near Oderbrück in the Harz Mountains ; 51 ° 46 ′ 20 ″ N , 10 ° 33 ′ 58 ″ E
Source height	approx. 812 m above sea level NHN
muzzle	near Katlenburg in the Rhume coordinates: 51 ° 40 ′ 44 ″ N , 10 ° 6 ′ 11 ″ E 51 ° 40 ′ 44 ″ N , 10 ° 6 ′ 11 ″ E;
Mouth height	approx. 137 m above sea level NHN
Height difference	approx. 675 m
Bottom slope	approx. 12 ‰
length	56.1 km
Catchment area	approx. 384.66 km²
Reservoirs flowed through	Oderteich , Oder reservoir
Small towns	Bad Lauterberg

The Oder in its source area, the Oderbruch

The Oder above the Oderteich

The Oder near Wulften am Harz

The Oder below the Oderberg

Mouth of the Sperrlutter into the Oder

The Oder is a 56.1 km long, eastern and right tributary of the Rhume in the districts of Goslar , Göttingen and Northeim in southeastern Lower Saxony ( Germany ). It flows in the Harz and in the southwestern Harz foreland.

geography

course

The Oder rises in the Goslar district in the Upper Harz . Its source is in the Harz National Park around 1.3 km north-north-west of the Achtermannshöhe and around 1 km south-east of Oderbrück , a district of the town of Braunlage . Your in the southern part of the Brockenfeld in the Oderbruch at about 812 m above sea level. The source located at the NHN is called "Odersprung".

The Abbe , Große Bode , Ecker and Kalte Bode rivers have their respective headwaters on the Brockenfeld and thus near the Odersprung ; the triangular post stands on the eastern edge of the Brockenfeld .

After the Oder in Oderbrück has crossed federal highway 4 in an east-west direction, it is dammed for the first time west of the settlement in the Oderteich , where it bends south. Below this reservoir it passes the Rehberg with the Hohe Klippen to the west and the Hahnenkleeklippen to the east . A few kilometers further down the river it flows through the Sankt Andreasberg district of Oderhaus , where the Trutenbeek flows into it. Then it is dammed southwest of the Odertal sawmill , where it leaves the Harz National Park and at the same time flows into the Harz Nature Park , to the Oder reservoir.

After the subsequent confluence of the Sperrlutter , the Oder crosses the core town of Bad Lauterberg and leaves the Harz. In the city, the river bends towards the west after the Lutter flows into it. Then it flows north past Pöhlde , where it leaves the Harz Nature Park, and through Hattorf am Harz , where it takes in the Sieber River coming from the northeast . It passes the Rotenberg ridge to the north and gradually runs through Wulften am Harz .

Finally opens the Oder in Katlenburg coming from the east to about 137 m in the line influx Rhume .

Catchment area and tributaries

The tributaries of the Oder, whose catchment area is about 384.66 km², include (viewed downstream; l = left-hand side; r = right-hand side):

Bremke (r)
Eichelngraben (r)
Beber (Pöhlder Bach) (l)
Sieber (r)
Hackenbach (r)

Localities

Localities on the Oder are:

Hydrography

The Oder and its largest tributary, the Sieber, lose water on their way through the southern Harz gypsum karst region to the Rhume spring , located to the south . This was proven by dyeing tests in the course of several hydrological investigations of the Rhume spring, as early as 1910 at Eichelbach near Herzberg by Karl Thürnau (with six kilograms of uranine ), then several times, e.g. in 1980 by the Lower Saxony State Office for Soil Research, at Sieber near Hörden and at Or near Scharzfeld. The large extent of the water losses is mainly explained by the fact that the ridge of the Rotenberg keeps the mighty gravel deposits of the Oder from the valley of the Rhume like a dam, but not the water flowing in the gravel, which flows through the sometimes fissured or karstification- capable rock layers of the Rotenberg can get deeper Rhumequelle.

Despite the water losses, the Oder is the larger, richer river when it flows into the Rhume, i.e. actually the main river. It is noteworthy that a similar situation also exists at the confluence of the Rhume with the Leine and again with its confluence with the Aller . This makes the Oder hydrographically the main river of the Aller river system.

Glacial embossing

During the Pleistocene , the upper reaches of the Oder in particular were shaped by the Harz's own glaciation. From a plateau glacier located between the Bruchberg , the Sonnenberg and the Achtermannshöhe , in the area of the Oderteich, a glacier tongue came down into the valley. In the area below the Hahnenklee cliffs you can still find the clearest traces of the Harz glaciation in the entire mountain range. In addition to several include Endmoränenbögen , Kames and kettle holes also glazifluviale and glaciolimnic sediments. The findings so far all point to the last ice age . Traces of earlier icing phases are no longer visible due to the strong periglacial and warm-time overprinting.

Oderaue nature reserve

Between Scharzfeld and Katlenburg, the Oder flows through the Oderaue nature reserve, which was designated in 2007 and covers around 510 hectares (NSG no. 378334).