Big moat and ship moat

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Großer Graben
upper reaches: Schiffgraben-Ost
GroßerGrabenSchiffgraben.png
Data
Water code DE : 56889
location Lower Saxony / Saxony-Anhalt , Germany
River system Elbe
Drain over Bode  → Saale  → Elbe  → North Sea
source Bifurcation point
52 ° 3 ′ 0 ″  N , 10 ° 42 ′ 0 ″  E
Source height 86  m above sea level NHN
muzzle 6 km east of Oschersleben as Lehnertsgraben Coordinates: 52 ° 0 '28 "  N , 11 ° 18' 22"  E 52 ° 0 '28 "  N , 11 ° 18' 22"  E
Mouth height 76  m above sea level NHN
Height difference 10 m
Bottom slope 0.23 ‰
length 43.6 km
Discharge at the gauge Oschersleben
A Eo : 838 km²
Location: 6 km above the mouth 		NNQ (08/14/1998)
MNQ 1987–2014
MQ 1987–2014
Mq 1987–2014
 MHQ 1987–2014
HHQ (01/19/1987) 		137 l / s
465 l / s
2.38 m³ / s
2.8 l / (s km²)
 10.8 m³ / s
29.2 m³ / s
Left tributaries Schöninger Aue
Right tributaries Deersheimer Aue , Kalbkebach
Medium-sized cities Oschersleben
Residents in the catchment area 44,100 (Saxony-Anhalt)
Water body SAL18OW01-00
Großer Graben and Schiffgraben between Neuwegersleben and Neudamm residential area

Großer Graben and Schiffgraben between Neuwegersleben and Neudamm residential area

Schiffgraben-West
Schiffgraben-West / Neuer Graben
The Schiffgraben-West near Hornburg below the confluence with the Neuer Graben

The Schiffgraben-West near Hornburg below the confluence with the Neuer Graben

Data
Water code DE : 48248
location Lower Saxony / Saxony-Anhalt , Germany
River system Weser
Drain over Ilse  → Oker  → Aller  → Weser  → North Sea
source Bifurcation point
52 ° 3 ′ 0 ″  N , 10 ° 42 ′ 0 ″  E
Source height 86  m above sea level NHN
muzzle In the mill rope
52 ° 3 ′ 2 ″  N , 10 ° 34 ′ 52 ″  E
Mouth height 85  m above sea level NHN
Height difference 1 m
Bottom slope 0.1 ‰
length 10.2 km
Catchment area 55.11 km²
Right tributaries Neuer Graben, Hellebach
Small towns Hornburg
Water body NLWKN : 15018, LHW: WESOW25-00

The Große Graben and the Schiffgraben in the Große Bruch in the northern Harz foreland are a contiguous, artificial river of 46 kilometers in length with mouths at both ends. It is fed by tributaries from the side and from the damp bottom of the Great Break. To the west of the bridge embankment of the B 79 near Mattierzoll , the water is called Schiffgraben , the eastern three quarters are called Großer Graben . In the apex area, the water level is about 86  m above sea level. NHN .

course

The no-flow border area ( pseudobifurcation ) is located in the section known as the Schiffgraben about three to four kilometers west of the name boundary at the level of the village of Hedeper . The sections are designated as Schiffgraben-West and Schiffgraben-Ost according to the direction of discharge . The Neue Graben runs parallel to the north of the Schiffgraben and also splits in both directions. The Schiffgraben-West joins the Neuer Graben south of Achim and meets the arm of the Ilse , known as Mühlenilse , at Hornburg , shortly before it flows into the Oker at Börßum . In terms of water management, Schiffgraben-West and Neuer Graben are regarded as one body of water by the State of Lower Saxony, while Schiffgraben-Ost is assigned to the water body of the Great Grave.

The Große Graben also has numerous parallel waters. It meets the Bode in Oschersleben , where a measuring point has been set up since 1961 (altitude 76.56  m above sea level ). There it bends north towards the town center. Under the name Lehnertsgraben , it runs a further six kilometers and flows east of Oschersleben at an altitude of about 74  m above sea level. NHN in the Bode.

About 22 kilometers of the water including the pseudobifurcation form the state border between Lower Saxony (districts Wolfenbüttel and Helmstedt ) in the north and Saxony-Anhalt ( district Harz ) in the south. A further seven kilometers of the large ditch correspond to the border between the Saxony-Anhalt districts of Harz and Börde .

Coordinates:

Water quality

The entire body of water is classified as an artificial water body, correspondingly the structural quality is inadequate throughout the course, both in Lower Saxony and in Saxony-Anhalt. This is equivalent to a structure grade V. Although the chemical quality is “good” throughout the process, the biological and ecological quality are classified as “bad” by the authorities of both federal states. Some tributaries score slightly better with the grade II – III, but their structural quality is consistently rated as “Heavy Modified Water Body” or as artificial bodies of water.

The entry of fertilizers and pesticides from intensive agriculture as well as the erosion of the loess soil and the associated silting is a major problem for ecological quality. The latter is intensified, especially in the section flowing westwards, due to the low flow velocity and the occasional dryness. All bodies of water are almost completely unshaded and tend to have lush growth of swamp and aquatic plants. On the other hand, species on the Red List such as mayflies (Caenis luctosa) and some species of beetles have been identified.

History of the moat

The Principality of Braunschweig-Wolfenbüttel regularly looked for a politically stable and possibly duty-free shipping route to the North Sea. The natural route over Aller and Weser was severely hindered by the customs duties in Celle and Bremen. The city of Braunschweig had to be crossed from the Wolfenbüttel residence, with which the principality was chronically in dispute and whose river course was heavily obstructed. Duke Julius therefore commissioned in 1575 its builder Willem de Raet , the natural connection between Oker and Bode in the Great break to consider their suitability for a way to the Elbe. De Raet toured the area between Hornburg and Oschersleben and the Holtemme between Harz and Halberstadt . His report was positive: making it navigable would not only be technically feasible, but also financially feasible by selling the peat extracted. A weir and possibly dams would have to be built in order to achieve an even water level in the trenches and to prevent the water from flowing away.

The already existing border location of the Great Rupture and the use of the other river routes up to the Elbe required extensive diplomatic preparation for this project. The Diocese of Halberstadt belonged to the sphere of influence of the Dukes of Braunschweig-Wolfenbüttel since 1566. The rulers of Brandenburg and Saxony were informed of the project in February 1576 and signaled their support. Wilhelm von Hessen warned Julius, however, of significantly higher costs and doubted the technical feasibility. A skipper applied for the project in 1581, and there is also a letter from 1583 to a merchant in Amsterdam in which the project was advertised. It was probably never implemented. The name Schiffgraben has been passed down, but it is not on record that a groundbreaking ceremony was ever undertaken for the realization.

Web links

Commons : Großer Graben und Schiffgraben  - Collection of images, videos and audio files

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Individual evidence

  1. ↑ a b c d Topographic map 1: 50,000 Land Lower Saxony, as of 2000
  2. ↑ GPS track Großer Graben – Schiffgraben-Ost
  3. ↑ German Hydrological Yearbook Royal Elbe River Basin, Part I, 2014. (PDF) State Agency for flood protection and water Saxony-Anhalt, S. 214 , accessed on November 3, 2018 (In: lhw.sachsen-anhalt.de).
  4. ↑ NLWKN: Inventory of the implementation of the EU Water Framework Directive, processing area Oker. Braunschweig November 2004, Table 3.
  5. ↑ NLWKN : Area directory for the Lower Saxony hydrographic map. Status 2010, p. 55. FV_Weser.pdf, retrieved from Umwelt.niedersachsen.de on August 19, 2013.
  6. ↑ Feasibility and acceptance study for the renaturation and site-appropriate use of wet grassland on former fen sites in the Green Belt. (PDF; 1.4 MB) German Federal Environment Foundation, 2007, pp. 20 and 21, on: dbu.de.
  7. ↑ State Office for Flood Protection and Water Management Saxony-Anhalt: Report on the quality of flowing waters and lakes in Saxony-Anhalt 2005-2008 , Magdeburg December 2011.
  8. ↑ NLWKN: water quality report Oker 2002. Braunschweig in October 2002.
  9. ↑ a b Theodor Müller: Shipping and rafting in the river area of ​​the Oker. Braunschweig 1968, p. 89 ff.