Kleine Aller
Encyclopedia
The Kleine Aller is a tributary of the Aller
and Aller Canal
in the German state of Lower Saxony
. It is about 15 kilometres (9.3 mi) long and up to 5 metres (16.4 ft) wide, and flows from north to south through the district of Gifhorn and the city of Wolfsburg
.
village of Wiswedel at 78 m above sea level. It drains the Kiebitzmoor west of Tülau
, through a system of ditches that has been continually expanded over the years, and also drains the Vogelmoor north of Barwedel
. In this region it is joined by the tributary of the Rhodische Aller. Finally the Kleine Aller flows southwards, past Bergfeld, Barwedel
, Tiddische
, Hoitlingen and Jembke
. From Jembke it forms the border between the district of Gifhorn and the city of Wolfsburg. The river also passes Wolfsburg-Brackstedt and Wolfsburg-Warmenau to enter the Aller Canal
south of Weyhausen
at a height of 55.5 m above sea level and at a point a few hundred metres after it branches away from the River Aller
itself.
The sections near Tülau, Bergefeld and Tiddische have been renaturalised and, in places, a new river channel has been dug out. The near-natural areas thus created have been planted with alder
. This provides important areas of shade because much of the river is directly illuminated by the sun, something which leads to rapid weed growth and choking of the river bed.
, the Saale glaciation. The ice sheets shaped the terrain over 100,000 years ago with their ground moraines. The streams acted as drainage channels for the higher lying areas of geest
in the Aller
glacial valley.
In the Middle Ages
the valley of the Kleine Aller created a natural, north-south oriented border between two regions. These were the Boldecker Land
in the west and the historic landscape of the Vorsfelder Werder in the east.
The Kleine Aller has been able to carve out a valley during the course of its existence which, in its middle reaches, is about 10 m deep and about 1,000 m wide in which a eutrophic peat fen
(Niedermoor) has become established. In earlier times the valley was only used as grassland due to frequent flooding; today the river meadows are mainly used for arable farming. The old meander
ing Kleine Aller was straightened and canalised in 1865 along almosts its entire length. The river bed was also raised. The changes to the river and the lack of flooding has enabled the land in the valley depression of the Kleine Aller to be used as farmland.
assesses the chemical water pollution
of the Kleine Aller as variable. The values for organic pollution, nitrate, ammonium and phosphate contamination vary from lightly polluted to very heavily polluted. Ammonium levels in particular suffer from wide variations and sometimes high values. This is due to the fact that the waterway receives the discharge from five sewage works and that the nitrogen content in these installations has not been reduced sufficiently.
Aller
The Aller is a river, long, in the states of Saxony-Anhalt and Lower Saxony in Germany. It is a right-hand, and hence eastern, tributary of the River Weser and is also its largest tributary. Its last form the Lower Aller federal waterway...
and Aller Canal
Aller Canal
The Aller Canal is a canal built in the mid-19th century in the German state of Lower Saxony. The canal is long and runs between Wolfsburg and Gifhorn. It was built to protect agricultural land from flooding by the river Aller...
in the German state of Lower Saxony
Lower Saxony
Lower Saxony is a German state situated in north-western Germany and is second in area and fourth in population among the sixteen states of Germany...
. It is about 15 kilometres (9.3 mi) long and up to 5 metres (16.4 ft) wide, and flows from north to south through the district of Gifhorn and the city of Wolfsburg
Wolfsburg
Wolfsburg is a town in Lower Saxony, Germany. It is located on the River Aller northeast of Braunschweig , and is mainly notable as the headquarters of Volkswagen AG...
.
Course
The Kleine Aller rises in the BromeBrome
Brome can refer to:*several species of grass, see Bromus*Brome, Suffolk*Brome, Germany, a municipality in Lower Saxony, Germany*Brome, Quebec, a village in Quebec, Canada* Brome, a former provincial electoral district in Quebec now part of Brome-Missisquoi...
village of Wiswedel at 78 m above sea level. It drains the Kiebitzmoor west of Tülau
Tülau
Tülau is a municipality in the district of Gifhorn, in Lower Saxony, Germany....
, through a system of ditches that has been continually expanded over the years, and also drains the Vogelmoor north of Barwedel
Barwedel
Barwedel is a municipality in the district of Gifhorn, in Lower Saxony, Germany....
. In this region it is joined by the tributary of the Rhodische Aller. Finally the Kleine Aller flows southwards, past Bergfeld, Barwedel
Barwedel
Barwedel is a municipality in the district of Gifhorn, in Lower Saxony, Germany....
, Tiddische
Tiddische
Tiddische is a municipality in the district of Gifhorn, in Lower Saxony, Germany....
, Hoitlingen and Jembke
Jembke
Jembke is a municipality in the district of Gifhorn, in Lower Saxony, Germany....
. From Jembke it forms the border between the district of Gifhorn and the city of Wolfsburg. The river also passes Wolfsburg-Brackstedt and Wolfsburg-Warmenau to enter the Aller Canal
Aller Canal
The Aller Canal is a canal built in the mid-19th century in the German state of Lower Saxony. The canal is long and runs between Wolfsburg and Gifhorn. It was built to protect agricultural land from flooding by the river Aller...
south of Weyhausen
Weyhausen
Weyhausen is a municipality in the district of Gifhorn, in Lower Saxony, Germany.-History:The earliest surviving record dates from 1344, naming the settlement as Weydehusen. In 1350 it was rebuilt following destruction by fire...
at a height of 55.5 m above sea level and at a point a few hundred metres after it branches away from the River Aller
Aller
The Aller is a river, long, in the states of Saxony-Anhalt and Lower Saxony in Germany. It is a right-hand, and hence eastern, tributary of the River Weser and is also its largest tributary. Its last form the Lower Aller federal waterway...
itself.
The sections near Tülau, Bergefeld and Tiddische have been renaturalised and, in places, a new river channel has been dug out. The near-natural areas thus created have been planted with alder
Alder
Alder is the common name of a genus of flowering plants belonging to the birch family . The genus comprises about 30 species of monoecious trees and shrubs, few reaching large size, distributed throughout the North Temperate Zone and in the Americas along the Andes southwards to...
. This provides important areas of shade because much of the river is directly illuminated by the sun, something which leads to rapid weed growth and choking of the river bed.
Formation and history
The river channel was formed, like the surrounding landscape, in the penultimate ice ageIce age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
, the Saale glaciation. The ice sheets shaped the terrain over 100,000 years ago with their ground moraines. The streams acted as drainage channels for the higher lying areas of geest
Geest (topography)
Geest is a type of slightly raised landscape that occurs in the plains of in Northern Germany, the Northern Netherlands and Denmark. It is a landscape of sandy and gravelly soils, usually mantled by a heathland vegetation, comprising glacial deposits left behind after the last ice age during the...
in the Aller
Aller
The Aller is a river, long, in the states of Saxony-Anhalt and Lower Saxony in Germany. It is a right-hand, and hence eastern, tributary of the River Weser and is also its largest tributary. Its last form the Lower Aller federal waterway...
glacial valley.
In the Middle Ages
Middle Ages
The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...
the valley of the Kleine Aller created a natural, north-south oriented border between two regions. These were the Boldecker Land
Boldecker Land
Boldecker Land is a municipality in the district of Gifhorn, in Lower Saxony, Germany. It is situated along the river Aller, approx. 12 km east of Gifhorn, and 8 km northwest of Wolfsburg. Its seat is in the village Weyhausen.-Samtgemeinde council:...
in the west and the historic landscape of the Vorsfelder Werder in the east.
The Kleine Aller has been able to carve out a valley during the course of its existence which, in its middle reaches, is about 10 m deep and about 1,000 m wide in which a eutrophic peat fen
Fen
A fen is a type of wetland fed by mineral-rich surface water or groundwater. Fens are characterised by their water chemistry, which is neutral or alkaline, with relatively high dissolved mineral levels but few other plant nutrients...
(Niedermoor) has become established. In earlier times the valley was only used as grassland due to frequent flooding; today the river meadows are mainly used for arable farming. The old meander
Meander
A meander in general is a bend in a sinuous watercourse. A meander is formed when the moving water in a stream erodes the outer banks and widens its valley. A stream of any volume may assume a meandering course, alternately eroding sediments from the outside of a bend and depositing them on the...
ing Kleine Aller was straightened and canalised in 1865 along almosts its entire length. The river bed was also raised. The changes to the river and the lack of flooding has enabled the land in the valley depression of the Kleine Aller to be used as farmland.
Water quality
Near Warmenau there has been a water quality station since 1967, where water quality has been regularly tested since 1976. The 2004 Lower Saxon water quality reportWater quality
Water quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
assesses the chemical water pollution
Water pollution
Water pollution is the contamination of water bodies . Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds....
of the Kleine Aller as variable. The values for organic pollution, nitrate, ammonium and phosphate contamination vary from lightly polluted to very heavily polluted. Ammonium levels in particular suffer from wide variations and sometimes high values. This is due to the fact that the waterway receives the discharge from five sewage works and that the nitrogen content in these installations has not been reduced sufficiently.