Inkwilersee
| Inkwilersee | ||
|---|---|---|
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| sunrise | ||
| Geographical location | Swiss plateau | |
| Drain | Seebach | |
| Places on the shore | Inkwil , Bolken | |
| Data | ||
| Coordinates | 616 922 / 227 481 | |
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| Altitude above sea level |
461 m above sea level M. geo.admin.ch |
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| surface | 10.16 hectares | |
| length | 500 m | |
| width | 300 m | |
| Maximum depth | 6 m | |
| Middle deep | 2.9 m | |
The Inkwilersee is a small lake on the border of the Swiss communities Inkwil , Canton Bern , and Bolken , Canton Solothurn .
It is about 500 meters long and 300 meters wide, its mean water level is 461 m. ü. M., the mean depth is 2.9 m and it has a surface of about 10 hectares.
history
The lake is around 10,000 years old. Like the Burgäschisee, the Inkwilersee is also a small lake formed from dead ice holes on the border between the cantons of Solothurn and Bern. There were already numerous settlements on the lake shore during the pile dwelling period. Objects found during excavations were found in various places. In spring 2007 the pile dwellings (only under water) were examined by divers. They found spearheads and tools. The municipal boundary Bolken-Inkwil goes through the lake and over the Inseli (the larger of the small islands). The lake used to be called Bolkensee and belonged to the municipality of Bolken. The remains of Bronze Age pile dwellings have been discovered on both islands in the lake .
In the same period and in a comparable way as the Inkwilersee, the much smaller Lobsigesee, about 33 km to the south-west, was formed near Seedorf in the canton of Bern.
location
In the middle of the lake there is an island, near the maximum depth of 6 m. The Inkwilersee is drained by the Seebach , which flows into the Aare about 5 km further north. There is a footpath around the reed belt of the lake. A few kilometers from the Inkwilersee lies the Burgäschisee, which is about twice as large .
ecology
Siltation
In a pilot project, the pond roses in the Inkwilersee were mowed between August 19 and 24, 2002. With the harvest of the pond roses, the silting process should be slowed down and the lifespan of the lake extended. The cantonal office for the environment feared that the lake could silt up completely in approx. 150 years without measures. Appropriate concepts for prevention are developed. The pond roses were mowed with a special mowing boat (manatee) and then transported to the shore (pond rose loading). Around three quarters of the pond rose population was mowed. The size of the harvest was determined in such a way that the protection of the flora and fauna was guaranteed. On the bank, the pond roses were chopped up with a chopper and prepared for removal. The pond roses were used by the Kompogas AG company to generate renewable energy (Kompogas).
Lack of oxygen / fish death
The Inkwilersee is a strongly eutrophic lake, ie it is rich in nutrients and poor in oxygen. In the past, this has resulted in acute oxygen depletion and the associated fish deaths in long warm phases - most recently at the end of August 2009 and again in 2011. In 2009, the fire brigade and army had to aerate the lake with water fountains for several days to restore the oxygen content to increase. The shallow depth of the Inkwilersee favors the rapid warming of the water, but is sufficient for the formation of a hypolimnion . Fish deaths, as in August 2009 and 2011, can occur when winds set in during persistent warm phases that break up the stratification of the lake and mix the low-oxygen deep water with the rest of the water. In 2011, some of the fish were rescued by fishing with nets and releasing them in the nearby Aare. Smaller fish were able to survive in the two small tributaries into which fresh water from hydrants was introduced.
Web links
- Website Inkwilersee
- Kleinseen - Der Inkwilersee - Official Website Canton Solothurn
- Wildlife around the Inkwilersee
Individual evidence
- ↑ a b Map Inkwilersee. In: map.geo.admin.ch. Swiss Confederation and Cantons, accessed on September 27, 2017 .