Egå Engsø

Egå Engsø
View of the eastern end of Egå Engsø, from the bird tower.
Location	Midtjylland region
Coordinates	56°13′05″N 10°13′16″E / 56.218°N 10.221°E / 56.218; 10.221Coordinates: 56°13′05″N 10°13′16″E / 56.218°N 10.221°E / 56.218; 10.221
Type	recreated lake and wet meadow
Primary inflows	Egå, Ellebækken
Primary outflows	Egå
Basin countries	Denmark
Surface area	1.15 km2 (0.44 sq mi)
Average depth	1 m (3 ft 3 in)
Max. depth	1.7 m (5 ft 7 in)
Shore length1	5.2 km (3.2 mi)
Settlements	Aarhus
1 Shore length is not a well-defined measure.

Egå Engsø is an artificial lake and wetland site located in the north of the town of Aarhus between Vejlby, Risskov and Lystrup. Engsø means 'meadow lake' and Egå means 'oak stream', referring to the stream that drains the lake into the Aarhus bay. The lake area is bordered by the Djursland motorway to the north and the Aarhus-Grenaa railway and the municipal heating pipes from Studstrup Power Station to the south and west.

Egå Engsø was created by re-flooding meadows on land previously drained in the 1950s for agricultural use. By the 1990s the water quality and natural ecosystem in and around the Egå river into which the site drained had declined due to the effect of nitrate fertilizer (eutrophication) use, through intensive farming in the area. Aarhus Municipality, Aarhus County and the Danish Forest and Nature Agency resolved to construct the lake as part of Vandmiljøplan II (English: Action Plan for the Aquatic Environment II) from 1998 to reduce this effect through bacterial denitrification . Another major reason for initiating the project, have been the need for a strengthened defence against increasing rainfalls. The lake was created alongside work on the new Djursland motorway, and completed in 2006. Aarhus municipality is single owner.

The lake covers approximately 115 hectares (280 acres), with another c. 100 hectares (250 acres) hectares of reedbeds and meadows. Access to the lake is restricted in most places, as the wet meadows at the lake brinks are reserved for grazing cattle. The grazing helps to restrict the growth of shrubs and woody plants and maintain a natural meadow habitat. It also increases the biodiversity. The amount of water in the lake, varies a great deal (by design) with weather and season, but under normal conditions, the average depth is about 1 m. Water levels can rise by an additional meter or more. The lake contains a number of fish species, fishing is prohibited however, as is swimming.

On the south brink, there is a bird watching tower erected in 2007, whose construction was funded by Australian wine firm Banrock Station. The lake attracts many different bird species, often in large flocks, with 188 species registered up to 2015.