Location: |
Heidenheimer Str., 73447 Oberkochen.
B19 between Aalen and Heidenheim, southern exit to Oberkochen. (48.7720685, 10.0952854) |
Open: |
no restrictions. [2024] |
Fee: |
free. [2024] |
Classification: | Karst Spring |
Light: | n/a |
Dimension: |
Schwarzer Kocher:
Yavg=680 l/s, Ymax=4000 l/s, Ymin=50 l/s, A=499 m NN. Weißer Kocher: Yavg=420 l/s, Ymax=2900 l/s, Ymin=100 l/s, A=508 m NN, T=8.6 °C, pH=7.1. |
Guided tours: | self guided |
Photography: | allowed |
Accessibility: | yes |
Bibliography: | |
Address: |
Stadtverwaltung Oberkochen, Eugen-Bolz-Platz 1, 73447 Oberkochen, Tel: +49-7364-270.
E-mail:
Schwäbische Alb Tourismusverband e.V., Bismarckstraße 21, 72574 Bad Urach, Tel: +49-7125-93930–0. E-mail: |
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info. |
1539 | iron forge at the source of the Kocher river first mentioned in a document. |
1611 | there is a smelting furnace, an iron forge, a slag poche and a laboratory house at the source of the Kocher in Oberkochen. |
1644 | closed ironworks demolished. |
1645 | new slag washing plant built. |
1907 | slag washery demolished. |
JUN-2020 | recognised as an important geotope and geopoint of the UNESCO Swabian Alb Geopark. |
There is actually no such thing as a Kocherursprung (source of the Kocher), instead, there are around 20 small springs between Oberkochen and Aalen that flow into the Kocher. The Kocher is located north of the European watershed, which means that it drains into the Rhine and thus into the North Sea. The two main sources are the Ursprung des Schwarzen Kochers (source of the Black Kocher) and the Ursprung des Weißen Kochers (source of the White Kocher), the two largest tributaries of the Kocher. They are also known as the Schwarzer Kocherursprung and Weißer Kocherursprung respectively, which is shorter but, as Wikipedia rightly points out, grammatically incorrect. There is even a spring named Roter Kocher (Red Kocher) as well as Brunnenquelle, Edlenbachquelle, Hubertusquelle, Hungerbrunnen, Katzenbachquelle, Langertbrunnen, Luggenlohbrunnen and many more. The spring of the Red Kocher is not visible any more, it flows in pipes and first appears in a small lake, which now bears this name. However, when people talk about the source of the Kocher, they mean the source of the Schwarzer Kocher, which is located on the B19 at the southern end of Oberkochen. You could be forgiven for thinking that it has its own exit, as the Kocherursprung car park is located directly at the exit. From the confluence of the Schwarzer and Weißer Kocher rivers, it is known as the Kocher, the second-largest tributary of the Neckar. It is about 169 km long and has a catchment area of about 1960 km². Another note on the name, Kocher probably comes from the Celtic language, presumably from the word stem keu-k, to bend or curve, i.e. the winding river. In 795 it was written Cochane, in 1024 it was written Chochina, later Cochara and from about 1504 Kocher.
A special thing about the German language which is hard to understand for foreigners: many things actually have a gender and thus genderspecific pronomes are used. The Danube river is female, the Rhine is male. There is no reason, its just tradition, and it is necessary to simply memorize it, because there is no grammatical rule. That's different for the Kocher river, for which even the locals use both genders. German Wikipedia only uses the masculine form, but there are many documents which use the female form. We decided to follow Wikipedia, but obviously you can only enjoy this on the German page.
The source of the Schwarzer Kocher is a karst spring with several outlets which emerge from the slope debris. As is common with karst springs, the flow rate fluctuates greatly, but with an average of 680 l/s, it is the largest karst spring around Oberkochen. The catchment area is a wooded area with almost no human influence, and so the spring water is very clean. The spring is a protected natural monument, a wetland biotope with numerous protected plant and animal species, and also an archaeological site. The geology is relatively simple: a horizontal, water-resistant layer or aquiclude was cut through by the Urbrenz. The groundwater body above the impermeable layer therefore flows wherever this water dam is cut through and forms small springs. These springs flowing out of the mountain are known locally as Seichter Karst (shallow karst), whereas the deep springs on the southern side of the Alb are known as Tiefer Karst (deep karst). Those terms are actual geologic terms, but rather uncommon, the springs of the shallow karst are generally called contact springs while the deep karst springs are called vauclusian springs. After the watershed shifted to the south, the water no longer flows into the Brenz, but into the Kocher, which has captured the Urbrenz valley.
Even before 1539, there was an ironworks at the source of the Kocher, and it was closed during the Thirty Years' War before 1644. Bohnerz was smelted here, which was mined as cave sediment in karst crevices and caves in the area. It mainly came from the Zahnberg near Königsbronn and from the Nattheim area. Bohnerz, pea or bean-shaped, often concentric, sometimes hollow nodules, are concretions of brown ironstone ore which are found in loose sediments. But Stuferz from Aalen was also smelted, an oolitic brown iron sandstone from the Dogger (Middle Jurassic), which was mined until the 20th century in the Tiefer Stollen mine in nearby Wasseralfingen. Black slag remains, some with reddish iron residue can be found around the spring and in the riverbed. The monks in Königsbronn were the first to set up and operate such ironworks in the area. Later, secular lords also tried to make money from iron smelting. The ironworks at the source of the Kocher was first mentioned in a document in 1539, but it is not known how long it had been in existence at that time. It was certainly very small, only a few men worked here, and it had little influence on the neighbouring village. Although the village presumably benefited from being able to sell wood to the furnace. The demand for charcoal was very high. In 1611, it was recorded that there was a smelting furnace, an iron forge, a slag poche and a laboratory house at the source of the Kocher in Oberkochen. The Thirty Years' War began in 1618, and the smelter was probably closed at some point, whether due to a lack of raw materials, markets or labour is unknown. Some sources say that it was destroyed during the war, but it is more likely that it was closed, fell into disrepair and was eventually demolished.
A Schlackenwäsche (slag washing plant) appears very frequently in these descriptions, although it is not entirely clear what this is supposed to be. In the literature, the slag wash is often misinterpreted as an ironworks. The proximity to the spring has something to do with the need for water, which is not needed for a blast furnace. The blowers of the blast furnace were driven by an undershot water wheel in an artificially constructed cooker channel. The ore had a low iron content, so in addition to the pig iron there was a considerable amount of slag, which itself had a certain amount of iron. The slag was therefore a type of iron ore, and the slag washing was used to increase the iron content. The slag was smashed and crushed in a slag poche, a punching plant for slag. The heavy, iron-rich grains were extracted from the resulting sand by washing out the lighter ones, similar to panning for gold. This turned the waste material back into a raw material, an early form of recycling. Presumably there were also various uses for the non-ferrous part of the slag sand, it was used in road construction, as it was found in the Tiefental road south of Oberkochen. Nowadays, slag is also used as an additive in cement production and as a mineral fertilizer.
After the closure of the smelter, the reworking of the slag heaps south of the Kocher spring continued. A new slag washing plant was even built, and later slag from other ironworks was processed, but operations ceased in the middle of the 18th century. The building was converted into a residential building and stood until the early 20th century. This is probably the reason why the term Schlackenwäsche is still used for this site by the locals today.
It is quite astonishing that a karst object, a karst spring, almost exclusively leads to a mining-historical description here. The reason is obvious: the water from the spring was used as a source of power and for washing the slag. And even the name can be traced back to this: the Schwarzer Kocher (Black Kocher) was named after the dark slag at its ground. The Weißer Kocher, on the other hand, is named after the steep gradient just below the spring, which leads to white water or rapids in the stream.
If you are in a hurry, we recommend visiting the Black Kocher Spring, which is the main site and esily accessible. If you have a little more time, we also recommend visiting the White Kocher Spring. This spring has even been recognized by the UNESCO Swabian Alb GeoPark as an important geotope and geopoint. And if you want to see even more, you can start the spring hiking trail at the Schwarze Kocherquelle, which leads to the most beautiful karst springs in the area.