Akerselva or Akerselven ( en, Aker River) is a river which flows through
Oslo
Oslo ( , , or ; sma, Oslove) is the capital and most populous city of Norway. It constitutes both a county and a municipality. The municipality of Oslo had a population of in 2022, while the city's greater urban area had a population of ...
. It starts at
Maridalsvannet
Maridalsvannet ( en, Lake Maridal) is a lake in Maridalen, Oslo, Norway. It is the largest lake in the municipality of Oslo, and serves as the main drinking water supply for the city. The lake drains via the river Akerselva to the Oslofjord
...
in
Oslomarka
Marka is the name of the forested and hilly areas surrounding Oslo, Norway. It includes areas within the municipality of Oslo, but also large areas in Hole, Ringerike, Jevnaker, Lunner, Nittedal, Bærum, Asker, and other municipalities in Viken co ...
, and traverses the boroughs of
Nordre Aker
Nordre Aker (Northern Aker) is a borough of the city of Oslo, Norway.
History
This area became part of the city of Oslo in 1948. Before that it was a part of Aker municipality in the former Akershus county.
Demographics and housing
With a popul ...
,
Sagene
Sagene is a borough of the city of Oslo, Norway. The area became part of the city of Oslo (then Christiania) in 1859. The name Sagene itself is the plural of the Norwegian word for "saw", reflecting all the old industrial mechanical saws powered ...
,
Grünerløkka
Grünerløkka is a borough of the city of Oslo, Norway. Grünerløkka became part of the city of Oslo (then Christiania) in 1858. Grünerløkka was traditionally a working class district; however, since the late 20th century the area has increasi ...
, central Oslo and
Grønland, whereby it finally ends at
Paulsenkaien and
Oset in
Bjørvika
Bjørvika is a neighborhood in the Sentrum borough of Oslo, Norway. The area is an inlet in the inner Oslofjord, situated between Gamlebyen and Akershus Fortress. It serves as an outlet for the river Akerselva. Since the 2000s, it has been und ...
. The river is considered to be a part of the
Nordmarkvassdraget, and has the Norwegian
watercourse number 006.Z. The entire river is about long, and has a difference in elevation between source and mouth of approximately .
In the past, the river was utilized as a source of energy for local
industry
Industry may refer to:
Economics
* Industry (economics), a generally categorized branch of economic activity
* Industry (manufacturing), a specific branch of economic activity, typically in factories with machinery
* The wider industrial sector ...
, and along the river there are many old industrial buildings.
In the 1970s, the river was heavily contaminated after 150 years of industrial and sewage discharge. In the 1980s, a local initiative to limit emissions and revive the
flora
Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous) native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' gut flora'' or '' skin flora''.
E ...
and
fauna
Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is '' funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoo ...
of the river began.
Akerselva has largely been rehabilitated is now "Oslo’s green lung" and along the bank of the entire river from Grønland to Maridalsvannet there are park areas.
Salmon
Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...
run and spawn in the upper part of the river.
Early in March 2011, Oslo's water and wastewater department accidentally discharged of chlorine into the river near its headwaters, rendering the river virtually dead as of 11 March 2011. According to
Norwegian Broadcasting Corporation
NRK, an abbreviation of the Norwegian ''Norsk Rikskringkasting AS'', generally expressed in English as the Norwegian Broadcasting Corporation, is the Norwegian government-owned radio and television public broadcasting company, and the largest ...
, the discharge occurred at the water treatment plant Oset.
Akerselva død etter giftutslipp
- NRK 8. mars 2011.
Name
The first element is the genitive case of Aker, the name of the old farm and churchsite that has named several places in Oslo. The last element is the finite form of the noun ''elv'' ('river').
The river is considered to be the border between the eastern and the western part of Oslo. In the eastern part people treat the word ''elv'' as a feminine noun, so they say ''elva'' ('the river'). The westside dialect is influenced by Danish (considered a more appropriate language during the union with Denmark), where the feminine and masculine genders have merged into a common gender inflected like Norwegian masculine nouns. Therefore, people in the western part often treat ''elv'' as a masculine noun, causing them to say ''elven'' ('the river').
The Old Norse
Old Norse, Old Nordic, or Old Scandinavian, is a stage of development of North Germanic languages, North Germanic dialects before their final divergence into separate Nordic languages. Old Norse was spoken by inhabitants of Scandinavia and t ...
name of the river was ''Frysja'', and this old name has been revived as the name of a neighborhood along the river. The name is probably derived from the verb ''frusa'' 'froth
Foams are materials formed by trapping pockets of gas in a liquid or solid.
A bath sponge and the head on a glass of beer are examples of foams. In most foams, the volume of gas is large, with thin films of liquid or solid separating the r ...
', referring to the many waterfalls in the river.
Geology
Akerselva flows from Maridalsvannet north of the city to Bjørvika
Bjørvika is a neighborhood in the Sentrum borough of Oslo, Norway. The area is an inlet in the inner Oslofjord, situated between Gamlebyen and Akershus Fortress. It serves as an outlet for the river Akerselva. Since the 2000s, it has been und ...
, 9.8 km further down. The fall is 149 meters. The entire river course is in the construction zone, while the precipitation field is in Nordmarka.
The rocks in the ground below the river are syenite (northern market) and hornfels from Bjølsen and northwards, while the ground south of Bjølsen is mainly clay slate and tuber lime. Syenite and hornfels are hard rocks that are hard to decompose. The river is located in the geological Oslo field, where subsidence areas are formed by stretches in the earth's crust, blocks are separated and middle parts sink in, allowing for rivers to cut down. The softer rocks further south hard formed the basis for brickwork on Myraløkka and Øvre Foss (Våghalsen), which in the 1840s was the country's largest, and large slides in the river, hence the street name Leirfallsgata at the bottom of Grünerløkka. In Øvre Foss lies a slab of solidified volcanic melt that has come up in a crack, which is tougher and harder than lime and slate and a reason why the waterfall is here. Up in Nydalen, there are steep erosion cliffs that are part of the Grefsen moraine. The river has cut its way through thick masses of gravel, sand and clay that formed in front of the inland ice that receded about 9800 years ago (the Akert Step). At the largest bathtub at Stilla and at the gutters between the grasslands at Brekkedammen, there is visible syenite (circular swab) with clear scouring strips from the glacier. At Nedre Foss there is visible tuber lime, black clay slate and limestone (orthocer lime).
About 10,000 years ago, the sea rose 220 meters higher than today, about 9300 years ago the sea was 150 meters so that the Maridal waters were separated from the fjord and the Akerselva was born. , 6,000 years ago was the waterline at Myraløkka and 3,000 years ago at Cuba.
Waterfalls
The 20 waterfalls are, from above:
* Kjelsås fall
* Brekkefossen
* Nydalsfossen, also called Nygårdsfossen
* Gullhaugfossen, at Gullhaug square
* Bjølsenfossen (two falls, fall height 16 meters), at Treschow's bridge
* Lilleborgfossen, fall height 3 meters
* Hjulafossen, below the Vøyen Bridge, which together with the Våghalsen form the Vøyen Falls
* Daredevil, below the Beyer Bridge
* Upper Waterfall, also called the Seilduksfossen
* Nedre Foss, several falls, at the silo in Cuba
A lot of stone has been used in river banks and bridges: At the Vaterland Park, a rocky mountain of gray Østfold granite from Hvaler has been recreated, the same has been used in the bridges in Hausmann's bridge. Both Nybrua, Ankerbrua and Sannerbrua besides the millstone on Beyerbrua are in light, coarse-grained syenite.
References
{{coord, 59, 54, N, 10, 45, E, display=title, region:NO_type:river_source:GNS-enwiki
Rivers of Oslo
Rivers of Norway