About Vänern

Vänern is Sweden´s largest lake and has a catchment area of about 46 880 km2. Example of rivers that flow into Vänern are Klarälven, Upperudsälven, Byälven, Norsälven, Tidan and Lidan.

Lake Vänern has northern Europe´s largest freshwater archipelago with 22 000 islands, islets and skerries. The lake has plenty of nesting birds and is also an important resting site for migrating birds in the spring and autumn. 

The lake host many fish species; there are 38 permanent species in Vänern and both cold and warm-water species mix. The most common fish in the lake is smelt.

The catchment area is dominated by forest, about two-thirds of the surface. Arable and pasture is covering one-sixth, most of this located in the southern part of the lake.

Chart of Vänern

Some lake facts about Sweden´s three largest lakes.

                          

Vänern 

Vättern  

Mälaren     

Lake surface, km2

5 650

1 910

1 120

Max. depth, m

106

128

63

Average depth, m 

27

40

13

Volyme, km

153

78

14

Turnover rate, years

8-9

58-60

2-3

Catchment area, excluding lake surface, km2  

46 800*

4 400**

22 600*** 

Number of islands (>25 m2)

12 285 

858 

1 416

Shore length, including islands, km

4 500

800

2 400

Drinking water (numbers of persons)

800 000

250 000

1 500 000

Water regulations, normal, m 

0,7-0,8 

0,3-0,4 

0,7 

Water transperency, m

4-6 

10-15

1-3 

Phosphorus, normal  µg/l

6-8 

4-6 

20-60 

Nitrogen, normal mg/l 

0,8 

0,7-0,8 

0,6-2 

Chlorophyll, normal mg/m3 

2-3 

0,8-1,2 

3-20 

* 10 % of Sweden
** 1 % of Sweden
*** 5 % of Sweden