Dammträsk (

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

for "Pond Swamp") is a small man made

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

within the Tyresån Lake System, located in Haninge Municipality, south of central

Stockholm Stockholm () is the Capital city, capital and List of urban areas in Sweden by population, largest city of Sweden as well as the List of urban areas in the Nordic countries, largest urban area in Scandinavia. Approximately 980,000 people liv ...

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

. The lake receives water from Övre and Nedre Rudasjön south of the lake and empties into

Drevviken Drevviken is a lake in southern Stockholm, Sweden, shared by the four municipalities Stockholm, Haninge, Huddinge, and Tyresö. While much of the surrounding area is used for one-family houses, the lake and the green space north of it are conside ...

north of it. Located just south of the residential area Kvarntorp, and north of the densely populated central Haninge, the wetland lake receives considerable amount of nutritive salts.Tyreså Collaboration

Environmental impact

The lake and the surrounding wetlands, together with local forests, are regarded as a valuable local natural resource.Haninge Municipality, ''Kvarntorp'' However, while the lake system as a whole is regarded as sensitive to

surface runoff Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when th ...

, Dammträsk is already too contaminated to be regarded as vulnerable.Haninge Municipality, ''Dagvattenstrategi'' Water has been deliberately redirected from Rudasjön to Dammträsk, which reduces contamination of the downstream lake, Drevviken, since much of the waste is sedimented into the lake. The price to pay has been the dense vegetation in the lake. Two abandoned facilities by the lake, a

dry cleaner Dry cleaning is any cleaning process for clothing and textiles using a solvent other than water. Dry cleaning still involves liquid, but clothes are instead soaked in a water-free liquid solvent. Tetrachloroethylene (perchloroethylene), known in ...

and a

gas station A filling station, also known as a gas station () or petrol station (), is a facility that sells fuel and engine lubricants for motor vehicles. The most common fuels sold in the 2010s were gasoline (or petrol) and diesel fuel. Gasoline ...

, contaminated the surrounding area. A restoration project in 2005 removed 276 tons of earth containing

chlorinated hydrocarbons An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalently bonded atom of chlorine. The chloroalkane class ( alkanes with one or more hydrogens substituted by chlo ...

and 595 tons containing

petroleum Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons, and is found in geological formations. The name ''petroleum'' covers both naturally occurring unprocessed crud ...

.Stockholm County Council, ''Samarbete''

Biodiversity

An inventory of the local vegetation concluded there are 27 species of

vascular plant Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They al ...

s around the lake, which makes it relatively biodiverse (3/5 on a scale where 1 means high biodiversity). One of the interesting species of

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

s in the lake is

Common Mare's Tail ''Hippuris vulgaris'' (from Greek: ἵππος — ''horse'' and οὐρά — ''tail''), known as mare's-tail or common mare's-tail, is a common aquatic ecosystem, aquatic plant of Eurasia and North America ranging from Greenland to the Tibetan ...

. Grass carp have been introduced to the lake.

Notes

References

* * * * * {{DEFAULTSORT:Dammtrask Geography of Stockholm Lakes of Stockholm County

Environmental impact

Biodiversity

See also

Notes

References