The Kleine Aller is a tributary of the
Aller
Aller may refer to:
Places Rivers
* Aller (Germany), a major river in North Germany
*Aller (Asturian river), a river in Asturias, Spain
*River Aller, a small river on Exmoor in Somerset, England
Inhabited places in the United Kingdom
*Aller, Devo ...
in the German state of
Lower Saxony
Lower Saxony (german: Niedersachsen ; nds, Neddersassen; stq, Läichsaksen) is a German state (') in northwestern Germany. It is the second-largest state by land area, with , and fourth-largest in population (8 million in 2021) among the 16 ...
. It is about long and up to wide, and flows from north to south through the district of
Gifhorn
Gifhorn () is a town and capital of the district of 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 important cities nearby, ...
and the city of
Wolfsburg
Wolfsburg (; Eastphalian: ''Wulfsborg'') is the fifth largest city in the German state of Lower Saxony, located on the river Aller. It lies about east of Hanover and west of Berlin.
Wolfsburg is famous as the location of Volkswagen AG's hea ...
.
Course
The Kleine Aller rises in the
Brome village of Wiswedel at 78 m above
sea level
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised g ...
. 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
Barwedel is a municipality in the district of Gifhorn, in Lower Saxony, Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, a ...
. In this region it is joined by the tributary of the ''Rhodische Aller''. Finally the Kleine Aller flows southwards, past Bergfeld,
Barwedel
Barwedel is a municipality in the district of Gifhorn, in Lower Saxony, Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, a ...
,
Tiddische, Hoitlingen and
Jembke
Jembke is a municipality in the district of Gifhorn, in Lower Saxony, Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and ...
. 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
The Aller Canal (german: Allerkanal) 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 Alle ...
south of
Weyhausen
Weyhausen is a municipality in the district of Gifhorn, in Lower Saxony, Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, ...
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 may refer to:
Places Rivers
* Aller (Germany), a major river in North Germany
*Aller (Asturian river), a river in Asturias, Spain
*River Aller, a small river on Exmoor in Somerset, England
Inhabited places in the United Kingdom
*Aller, Devo ...
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
Alders are trees comprising the genus ''Alnus'' in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few sp ...
. 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 age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gree ...
, the
Saale glaciation
The Saale glaciation or Saale Glaciation, sometimes referred to as the Saalian glaciation, Saale cold period (german: Saale-Kaltzeit), Saale complex (''Saale-Komplex'') or Saale glacial stage (''Saale-Glazial'', colloquially also the ''Saale-Eiszei ...
. The ice sheets shaped the terrain over 100,000 years ago with their
ground moraine
A moraine is any accumulation of unconsolidated debris (regolith and rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a glacier or ice shee ...
s. The streams acted as drainage channels for the higher lying areas of
geest
Geest is a type of landform, slightly raised above the surrounding countryside, that occurs on the plains of Northern Germany, the Northern Netherlands and Denmark. It is a landscape of sandy and gravelly soils formed as a glacial outwash plai ...
in the
Aller
Aller may refer to:
Places Rivers
* Aller (Germany), a major river in North Germany
*Aller (Asturian river), a river in Asturias, Spain
*River Aller, a small river on Exmoor in Somerset, England
Inhabited places in the United Kingdom
*Aller, Devo ...
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 ...
.
In the
Middle Ages
In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire a ...
the valley of the Kleine Aller created a natural, north-south oriented border between two regions. These were the
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.
Politic ...
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
Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytoplank ...
peat
fen
A fen is a type of peat-accumulating wetland fed by mineral-rich ground or surface water. It is one of the main types of wetlands along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known as mires. T ...
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
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) and deposits sediments on an inner, convex bank ...
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 reportKleine Aller Water Quality Report by the NLWKN
/ref> assesses the chemical water pollution
Water pollution (or aquatic pollution) is the contamination of water bodies, usually as a result of human activities, so that it negatively affects its uses. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water ...
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
Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable for discharge to the surrounding envir ...
and that the nitrogen content in these installations has not been reduced sufficiently.
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–Z
A
B
D
E
F
G
H
I
J
K
L
M
N
O
P
* Purrmühlenbach
R
S
T
*Tiefenbeek
*Trillkebach
*Trutenbeek
* Twiste
U
* Uffe
*Ulrichswas ...
References
External links
Water quality report on the Aller / Quelle 2004 by the State of Lower Saxony
{dead link, date=December 2017 , bot=InternetArchiveBot , fix-attempted=yes (pdf, 1 MB)
Rivers of Lower Saxony
Wolfsburg
Gifhorn (district)
Rivers of Germany