Groundwater- fed quarry
The upper Weiher is a groundwater- fed quarry, in Günztal near the Günz in the community wide valley in the district of Günzburg. Like the many other lakes in the Günz and in the east which are situated further Mindel created by gravel mining of the upper Weiher. Through this history of the Upper Weiher has an almost square shape. The peculiarity of the Oberrieder pond is that it is a very large lake - sometimes even said that it was the largest in Bavarian Swabia.
The size of the Oberrieder pond is probably also the reason that he is not as fast eutrophic and subsequently with water plants or algae accrues as smaller lakes.
In the southwestern part of the lake there are three small today, especially with white willow (Salix alba) vegetated islands. This arose because you have a land line that crossed the lake, did not want to move to the beginning of the phase of the gravel extraction. Therefore, these three islands on which stood the electricity pylons of this transmission line emerged. Later, the power line was but then moved around the lake.
Phase of the gravel extraction
Until about the year 2004 was the gravel plant in operation, which stood on a peninsula that protrudes on the northwestern shore into the lake. At the smaller excavator ponds that will connect directly to the southwest Oberrieder pond still mined gravel.
Subsequent use of the lake as a recreational area
- The northeastern shore of the lake was expanded to the bathing place many years ago, which is guarded by the lifeguard Krumbach. The area of the lake which is adjacent to this swimming area is separated from the rest of the lake by buoys, so do not interfere with swimmers, anglers, surfers and sailors who use the rest of the lake, each other.
- At the southwest lakeshore is the site of the sailing clubs Breitenthal.
- There is also a surf school right on the lake.
- Scuba diving is also possible in the upper Weiher.
Because of these multiple uses, good water quality, the cleanliness of bathing site and a large car park to the top Weiher is a well known and popular swimming not only in the immediate vicinity. The catchment area from which visitors to the Oberrieder pond come, dates back to Ulm.
On the peninsula on which once stood the gravel plant, a camp was built in 2005. Before there was this campsite, there was at the southeast corner of the lake a wild campsite, which was used mainly by permanent campers.
- Near the top Weiher is located on the Günz a hydroelectric power plant, which is operated by Überlandwerk Krumbach.
- The Günztal bicycle trail at the lake.
- Each year on New Year's Eve will take place New Year's Eve swimming lifeguard Krumbach at the top Weiher.