Aachtopf

47.8466666666678.8580555555556Koordinaten: 47 ° 50 '48 " N, 8 ° 51' 29" O

The Aachtopf (also: Aachquelle ) at Aach in Baden-Württemberg is the most water-rich karst spring in Germany. Here arises the Radolfzell Aach (also Hegauer Aach ), which flows into the lake after 32 km at Radolfzell.

Data

The source has an average bed of 8.590 l / s, but this is, as usual, karst springs, strongly dependent on the season and varies 1300-24000 l / s The water of the Aachquelle rises from a 18 m deep underground water cave and forms a small lake.

Water origin

The water of the karst spring comes mainly from the sinking between Immendingen and Möhringen and Fridingen Danube. The catchment area includes more swallow holes, eg in Neuhausen ob Eck and Heudorf Hegau. Approximately one-third of the bulk of the Aachquelle is due to such side tributaries.

From the Donauversinkung the water flows underground approximately 11.7 km at a speed of about 195 m / h through cavities to Aachtopf.

So that the upper Danube belongs entirely to the approximately 130 full days seepage to the river system of the Rhine. In order for a process could be in the future with further dissolution of the limestone caves to collapse the similar play of Wutach distraction, will have become at the end of the upper reaches of the Danube quite a tributary of the Rhine.

Environment

In the Waterside area of Aach and below the Aach pot in the river bed are other small sources. The southernmost proven exit point of the Danube water is the source of bleach at Singen. The Aachtopf is a popular weekend destination.

From the Middle Ages to around 1950, hydropower was used by numerous mills. Since 1935/36, the water is carried in a channel to a power company. Due to the use of water, both at the Württemberg Danube, as well as at the Baden Aach, it always came back to disputes over the water: on the Danube seepage holes were clogged again and again, or damming the water over the sip holes on. ( See: Donauversinkungsfall ). It was only after the establishment of the State of Baden- Württemberg a common solution could be found.

Research

1719 was the first time the presumption the spring water come from the Donauversinkung, in a paper by FW Breuninger expressed. However, proof was not until October 9, 1877, when the geologist Adolf Knop from the Technical University of Karlsruhe offset the water in the Donauversinkung with 10 kg of sodium fluorescein, 20 tonnes of salt and 1200 kg shale oil. After 60 hours, all three substances could be detected in the source container, which manifested itself in glorious green shining salt water with significantly kreosotartigem taste.

In 1886 there was the first diving attempt to 12 m depth, one of the world's first cave dives. There is the difficult to overcome nozzle, a throat, where the water has a strong current.

The spring cave was explored in the 1960s by Jochen Hasenmayer. It was discovered a hall with sinter pools and limestone residues, which indicates that this building was once an air- filled cave creek. In the years from 1980 Aach cave was explored extensively by Harald Schetter. Since 2001, Aach cave by Jürgen Bohnert, Frank Liedtke, Stephan Liedtke and Tobias Schmidt is re-measured. After 500 m north of the cave ends in a large Versturz, which is also seen on the surface as large sinkhole in the woods. On the northern edge of the sinkhole, the continuation of Aach cave was discovered after 14 years of excavation. Since the chemical composition of the water does not exactly corresponds with the cavity Aach here, it is assumed that there must be a plurality of feeders. Therefore he called the cave from here Danube cave.