The Aller Canal () is a canal built in the mid-19th century in the German state of

Lower Saxony Lower Saxony is a States of Germany, German state (') in Northern Germany, northwestern Germany. It is the second-largest state by land area, with , and fourth-largest in population (8 million in 2021) among the 16 ' of the Germany, Federal Re ...

. The canal is long and runs between

Wolfsburg Wolfsburg (; Eastphalian language, Eastphalian: ''Wulfsborg'') is the fifth-largest city in the Germany, German state of Lower Saxony, on the river Aller (Germany), Aller east of Hanover and west of Berlin. Wolfsburg is famous as the locat ...

and

Gifhorn Gifhorn () is a town and capital of the district of Gifhorn (district), Gifhorn in the east of Lower Saxony, Germany. It has a population of about 42,000 and is mainly influenced by the small distance to the more industrial and commercially import ...

. It was built to protect agricultural land from

flooding A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civi ...

by the river Aller. The nearly straight canal carries water from the Aller more quickly than the river itself can in its

meander A meander is one of a series of regular sinuous curves in the Channel (geography), channel of a river or other watercourse. It is produced as a watercourse erosion, erodes the sediments of an outer, concave bank (cut bank, cut bank or river cl ...

ing course through this section of the old

glacial valley U-shaped valleys, also called trough valleys or glacial troughs, are formed by the process of glaciation. They are characteristic of mountain glaciation in particular. They have a characteristic U shape in cross-section, with steep, straight s ...

Route

The Aller Canal was completed in 1863 after a three-year construction period. It begins near Weyhausen just beyond the city of

, where it is joined by the tributary of the

Kleine Aller The Kleine Aller is a tributary of the Aller (Germany), Aller in the German state of Lower Saxony. It is about long and up to wide, and flows from north to south through the district of Landkreis Gifhorn, Gifhorn and the city of Wolfsburg. C ...

. Here the Aller divides itself between its natural river channel and the canal. The canal runs in an almost straight line through the wetland of the

Barnbruch The Barnbruch is a wetland of international importance in the old glacial valley of the river Aller (Germany), Aller that provides a habitat for endangered species of birds, amphibians and insects. It lies between the city of Wolfsburg and town ...

as far as

where it passes the town to the south. West of Gifhorn the canal uses the upgraded and widened stream bed of the Hehlenriede and, 5 km west of Gifhorn, near Brenneckenbrück on the B 188, it rejoins the Aller. About a kilometre before that the water of the canal drops by about a metre over a

weir A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the water level. Weirs are also used to control the flow of water for outlets of l ...

. The river flows parallel and north of the canal by several kilometres and, in this flat area of the Aller's old

, forms tightly-spaced

meanders A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. It is produced as a watercourse erodes the sediments of an outer, concave bank ( cut bank or river cliff) and deposits sediments on an inn ...

which reduce the water velocity in the river.

Construction

The construction of the Aller Canal between 1860 and 1863 stemmed from a state treaty between

Prussia Prussia (; ; Old Prussian: ''Prūsija'') was a Germans, German state centred on the North European Plain that originated from the 1525 secularization of the Prussia (region), Prussian part of the State of the Teutonic Order. For centuries, ...

, the

Kingdom of Hanover The Kingdom of Hanover () was established in October 1814 by the Congress of Vienna, with the restoration of George III to his Hanoverian territories after the Napoleonic Wars, Napoleonic era. It succeeded the former Electorate of Hanover, and j ...

and

Duchy of Brunswick The Duchy of Brunswick () was a historical German state that ceased to exist in 1918. Its capital city, capital was the city of Braunschweig, Brunswick (). It was established as the successor state of the Principality of Brunswick-Wolfenbüttel ...

for the regulation of the Aller. Its purpose was to control the spring floods in the Aller valley and to assist in draining the former swampland of the

. The canal is only about 5 m wide and 1 m deep. To appreciate the feat achieved by its builders it should be borne in mind that, at the time, there was almost no technical equipment and workers had to excavate the channel by hand using shovels. A monument to the construction was erected by the canal between ''Brenneckenbrück'' and

-Winkel. It carries the following inscription: :''Allerkanal, erbaut 1860-63, Kostenaufwand 45.000 Thaler, den Bauern der Allerdörfer von Wolfsburg bis Diekhorst, die ihn schufen, dem Wasserbauinspektor August Hess in Celle, der ihn baute und den Männern, die ihn betreuten zum Gedenken'' ...which means: "To commemorate the Aller Canal, built 1860-63 at a cost of 45,000

thaler A thaler or taler ( ; , previously spelled ) is one of the large silver coins minted in the states and territories of the Holy Roman Empire and the Habsburg monarchy during the Early Modern period. A ''thaler'' size silver coin has a diameter o ...

s, and the farmers of the Aller villages from Wolfsburg to Diekhorst who created it, hydraulic engineer, August Hess, in Celle, who designed it, and the men he oversaw."

Water quality

The Lower Saxon

water quality Water quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through tr ...

report''Gewässergütebericht Aller / Quelle 2004'' des Niedersächsischen Landesbetriebs für Wasserwirtschaft, Küsten- und Naturschutz of 2004 assessed the chemical water contamination of the Aller Canal along with the river Aller itself as moderately polluted (water quality class II). Because the

fascine A fascine (pronounced ) is a rough bundle of wikt:brushwood, brushwood or other material used for strengthening an earthen structure, or making a path across uneven or wet terrain. Typical uses are protecting the banks of streams from erosion (a ...

s that secured the banks have largely rotted away, the canal has become a near-natural waterway. The canal runs through the deciduous woods of the Barnbruch, which provides shade. This prevents the growth of weeds in the river bed, unlike the river Aller which is unshaded in most places.

Tributaries

* Aller * Hehlenriede *

Mühlenriede Mühlenriede is a river of Lower Saxony, Germany. It flows into the Aller Canal southeast of Gifhorn. See also *List of rivers of Lower Saxony All rivers in the German state of Lower Saxony flow directly or indirectly into the North Sea. A� ...

* Rötgesbütteler Riede * Vollbütteler Riede

References

External links

Water quality report Aller /source 2004 from the state of Lower Saxony
(pdf, 1 MB) {{coord, 52.4778, N, 10.4653, E, source:wikidata-and-enwiki-cat-tree_region:DE, display=title Canals in Lower Saxony Wolfsburg Gifhorn (district) Canals opened in 1863 CAllerCanal