Irrbach (Ehebach)

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Irrbach
Data
location Steigerwald
  • Southern (Vorderer) Steigerwald

Bavaria

River system Rhine
Drain over Ehebach  → Aisch  → Regnitz  → Main  → Rhine  → North Sea
source approx. 150 m southwest of Markt Nordheim- Wüstphül in the curve of NEA 31
49 ° 34 ′ 1 ″  N , 10 ° 19 ′ 6 ″  E
Source height approx.  341  m above sea level NHN
muzzle approximately 0.6 km south west of Sugenheim- Krautostheim on a dirt road triangular coordinates: 49 ° 34 '22 "  N , 10 ° 22' 31"  O 49 ° 34 '22 "  N , 10 ° 22' 31"  O
Mouth height approx.  319  m above sea level NHN
Height difference approx. 22 m
Bottom slope approx. 4.2 ‰
length approx. 5.2 km

The Irrbach is a little over 6 km long brook in the area of Markt Nordheim in the Central Franconian district of Neustadt an der Aisch-Bad Windsheim , which flows into the upper Ehebach from the left and about west on the eastern border of the municipality of Markt Sugenheim near its parish village Krautostheim .

geography

course

The Irrbach arises about 150 meters southwest of the south-western group of houses of the Wüstphül settlement of Markt Nordheim , within which area or at the end of which it remains to its confluence with the neighboring municipality of Markt Sugenheim . There on the inside of the arch of the district road NEA 31 begins at about 341  m above sea level. NHN is an initially south-eastern, unstable water-bearing ditch next to dirt roads and property boundaries. After about 600 meters, it turns north-east for the next 1.2 km, now sporadically wooded areas next to the accompanying dirt road for the first time on the bank of the now more permanent trench.

At about 340  m above sea level. NHN it crosses the southeastern courtyard group of Wüstphül and immediately afterwards turns to the east. At the edge of a small forest area that soon follows to the fields in the south, its course begins to oscillate in an herbaceous depression between banks that are often tree-lined. After the forest he passes in the same way a gypsum pit on the south side of the seven humps , a subrosion landscape shaped by solute dolines. Then it flows the remaining almost kilometer to the St 2256 again as an almost straight and bare ditch between fields.

It crosses under the state road and splits on the other side at a wood at about 320  m above sea level. NHN in two lower courses. The right called Irrbach runs a good 300 meters straight, but now with tree cover, next to a field path as a border brook to Markt Sugenheim to the southeast and then flows to about 319  m above sea level. NHN about 0.6 km southwest of the outskirts of the parish village of Krautostheim from the left into the upper Ehebach, which itself is not a much larger ditch here.

The Irrbach flows after a 5.2 km long run with an average bottom slope of only about 4.2 ‰ about 22 meters below its origin.

The left branch of the Quellenbach, on the other hand, continues to flow about east in the area of ​​Markt Sugenheim , after about 0.4 km reaches the vicinity of the state road again and follows it to the southwestern outskirts of Krautostheim. After crossing under the road leading towards Humprechtsau , he passes the clarification pond on the southern outskirts and then reaches about 317  m above sea level. NHN from the left the Ehebach.

The Quellenbach flows after a 1.3 km long run with an average bed gradient of around 1.6 ‰ about 2 meters below its origin, it drains an area about 0.5 km² below the division.

Catchment area

The Irrbach (without Quellenbach) has a catchment area of ​​around 6.1 km², which, according to the proposed natural spatial structure, lies in the sub-area of ​​the southern (front) Steigerwald of the Steigerwald . The highest point is the summit of the Stellenberg at 422  m above sea level. NHN on its northern border. In turn it borders on the neighboring catchment areas

  • of the Geroldsbach in the north, which also drains further downwards via the Kleine Ehe into the Ehebach
  • of its own dividing arm Quellenbach only briefly in the east
  • of the upper Ehebach itself in the south, whose outflow over the Aisch and the Regnitz reaches the Main high above
  • the Schwemmseegraben in the west, which drains via the Gollach and Tauber much further down to the Main.

The hydrologically most important watershed is therefore the last-mentioned to the Gollach in the west, which is morphologically noticeable at most in its northern section.

The northern part of the catchment area on the southern slope of a ridge from In der Helle ( 416  m above sea level ) over the Stellenberg ( 422  m above sea level ) to the last to the spur ( 416  m above sea level ) of the Hohenkottenheim castle ruins on the Ostend is wooded a smaller forest island to the left of the middle reaches. The slightly larger one in the south is open and is mainly used for arable farming. The only place in the catchment area and also partly on the run is the scattered settlement of Wüstphül von Markt Nordheim , to which the entire catchment area belongs, with the exception of just one edge of the community of Weigenheim am Berg In der Helle .

In the catchment area there is mainly gypsum keuper ( Grabfeld formation ), with a significantly lower area share and mostly in the south also the geologically deeper Unterer Keuper . The gypsum keuper in the subsoil is indicated by the rare and less constant superficial inflows from the significantly higher elevations in the north, the sometimes restless elevation profile and the gypsum dolines in the area of ​​the nature reserve Gipshöhle Höllern and gypsum hill Sieben Buckel on the left of the middle reaches. There is a leaching cave around one kilometer long, designated as a geotope, just below ground level. (Access not public.) Since the runoff in the subroded subsoil is aligned with the direction of the fracture in the base plaster, the size of the catchment area determined on the basis of the height profile can differ significantly from its actual size.

The grobmaßstäbliche Geological Map 1: 500 000 shows a south to southeast running tectonic Horst about or maybe just left of the middle course, where is held before and after Gipskeuper the deeper Lower Keuper on the surface, conspicuously in the area of that nature reserve and gypsum mining; there is probably a generalization error here.

Tributaries and lakes

The Irrbach takes almost only inconsistent water-bearing ditches along field paths.

At the two farms of Wüstphül, which are separated from it, a 1.0 km long, inconsistent stream flows from the north-west from the edge of the forest with an approx. 2.2 km² surface catchment area, which divides into two arms in the area of ​​the northern settlement group of Wüstphül of which one flows through the two parts of the Hofsee, each about 0.3 hectares in size .

From the forest area to the left of the middle course, a meadow floodplain, divided in the upper area, runs southeast to the Irrbach, which is approx. 1.0 km long and has an approx. 0.4 km large basin, but not a marked course on the map and no recognizable course on aerial photos .

See also

Individual evidence

BayernAtlas ("BA")

Official online waterway map with a suitable section and the layers used here: Course and catchment area of ​​the Irrbach
General introduction without default settings and layers: BayernAtlas of the Bavarian State Government ( notes )

  1. ↑ a b c d e Height requested on the background layer Official map (right click).
  2. ↑ a b c d Length measured on the official map background layer .
  3. ↑ a b c d Catchment area measured on the official map background layer .
  4. ↑ a b c Height according to black lettering on the official map background layer .
  5. ↑ Geology according to the layer geological map 1: 500,000 .
  6. ↑ The area of ​​the lake measured on the official map background layer .

Others

  1. ^ Karl Albert Habbe: The natural space units on sheet 153 Bamberg - A bundle of problems and a proposal for a structure. In: Announcements of the Franconian Geographical Society 2003/2004, pp. 55–102 ( PDF download )

literature

Web links