Blies
Map of the catchment area; Schwarzenbach and Hornbach are also highlighted.
The assemblies is nearly 100 km long tributary of the Saar Saarland and Lorraine and crosses on their run from the northeast of the Saarland in the district of St. Wendel to the southern tip of the country several natural areas.
The assemblies with a water channel of 20.7 m³ / s at the mouth not only the largest tributary of the Saar, but hydrologically even their Hauptquellast since the Saar / s moderate runoff at this point is slightly smaller at 19.0 m³. Of the total catchment area at the mouth of the assemblies increases with 1889 by 3673 square kilometers and just over half.
However, the Assemblies of strictly hydrologic perspective itself tributary of the Black creek, providing, well before the confluence with the Saar, about half of the total runoff. However, the Schwarzenbach has again until almost doubled just before its mouth by the mouth of the horn Bach. In fact, it so is the system of assemblies to a very irregular compartments with three main branches, while the Saar has increased their water after the confluence of the Red and White Saar rather continuously.
- 5.1 Fauna
- 5.2 vegetation
- 6.1 railroads
- 6.2 Leisure
Natural areas of the watershed
The headwaters of the assemblies is between Selbach and Gronig on Momberg ( dialect Mommerich ) in Nohfelden Hirst 's mountain country with submontane to montane altitudinal zone ( typical plant occurrence: Quirlblättrige Weißwurz; Polygonatum verticillatum ).
Southward the Assemblies flows over a longer distance, thereby Bliesen, St. Wendel and Ottweiler passing through the prim - Blew - hill country with pronounced relief energy and a high proportion of forest (especially beech ). The floors offer agriculture here only moderate yield conditions. The valley meadows are partly under nature protection. On the southern edge of the natural environment of the river leaves the Saar- Hunsrück.
In Neunkirchen (Saar ) is the Bliestal part of the natural areas Saarkohlenwald and St. Ingberter Valley, also with a high proportion of forest (60 %). South of Blieskastel takes the assemblies in the natural environment Zweibrücker Westrich one - part of the Palatine - Saarland limestone area. The underflow in the area of Saar Pfalz- Saar district is part of Bliesgau. The addition reaching far beyond the Saarland natural area has a pleasant climate and a high proportion of rare and worthy of protection habitats ( eg lime limestone grasslands, orchards ) and species ( eg orchids ) ... From Bliesbruck ( German: Blew bridges) flows through the blew westward, first for 3.5 km through French territory and then for 16 km as border between France and Germany. In the border town of Sarreguemines ( German: Sarreguemines ) it opens in the Saar ( Saar at km 104.0 ).
Geology
In the upper reaches, in the rocks of the lower Rotliegend, form the assemblies and their tributaries spread gullies, further down V-shaped valleys and sole -shaped valleys. In the area of Spiemont at Oberlinxweiler the Bliestal is by recalcitrant Volcanic ( Kuselit ) concentrated ( Linxweiler gate). The assemblies then flows through the Ottweiler and Saarbrücken layers of the Carboniferous, then in the wider valley and once meandering layers of red sandstone and from Breitfurt again in a narrower valley layers of the Muschelkalk.
The assemblies will be the type of water associated with Auetalgewässer wider floodplain and in the lower reaches of the Mäandertalgewässern.
Hydrology
The water supply of the assemblies is subject to strong fluctuations. At the level of pure home the difference between high and low water levels in the range of several meters is located. The discharge rate fluctuated according to previous records between 2.9 m³ / s ( 24 July 1959) and 373 m³ / s ( 21 December 1993). With the floods in the years 1970 and 1993, the old town of Blieskastel was almost completely flooded. One reason for high property is the development of floodplains, whereby the natural flood retention area has been reduced. Artificial reservoirs like the end of the 1990s, completed in Ottweiler offer difficult pointwise replacement. Funding is therefore increasingly waters renaturation as that of Easter, which is regarded as a successful example.
At the Assemblies six levels are set on the German side ( in Oberthal, Alsfassen ( St. Wendel ), Ottweiler, Neunkirchen, Blieskastel, clean home ). By further level the tributaries Todbach, Easter, Schwarzenbach, Würzbach and Hetschenbach be observed.
The flood characteristics of the assemblies are located at more than twice the Saar. Your slightly higher average runoff is therefore not furthermore reflected in the low- water bed of the Assemblies; Thus, it appears not only in name as tributary at normal water level.
The catchment area of 1889 km ² and includes assemblies, surpassing that of almost equal size Saar; this includes at the confluence of 1784 km ². For its part, the catchment area of the assemblies at the site of the confluence of the main tributary, the Black creek, surpassed by its catchment area, the well has twice the area.
Use history
Drainage and irrigation cooperatives
Shore close up, fertile alluvial soil was developed from the mid-18th century by drainage measures in many parts of the Bliesaue. This development is closely linked to the irrigation and drainage cooperatives in Bliestal whose job it was to promote agricultural production, ie drainage for large water supply and irrigation during dry periods. Two of the original three water and soil associations are still active.
Irrigation and drainage cooperative Niederbexbach:
The irrigation and drainage cooperative Niederbexbach was founded in 1789 as a low Bexbacher Wässerungsanstalt on a voluntary basis. The Edict of Prince William Henry of Nassau -Saarbrücken from 1765 was replaced by the Bavarian Water Act in 1852. Since 1909, the cooperative is in its present form one of the few active drainage and irrigation cooperatives in southwestern Germany.
The total investment in the Wässerwiesen consists of the two assemblies weirs - the Haseler weir and the Holzauwehr -, twelve side locks in the main ditch and three other locks in the side ditches and the water ditches which have a total length of 16,800 m. The cooperative area that extends to the districts of Niederbexbach, Kohlhof, Limbach and Old Town, covers approximately 156 ha and 1,400 parcels.
The weir was Haseler 1748/50 built as a mill weir Haseler the mill and the Holzauwehr next to the former riverbed in the years 1779/81. During today's Haseler military during the years has been newly built south of the old location in Concrete 1937/38, which is obtained Holzauwehr been refurbished. Both systems are available as certificates of Saarland economic history historical monument.
Renovated Holzauwehr
Haseler mill weir
Besides lock " clo "
Mills
The mill industry is one of the oldest trades in the assemblies. In Breitfurt located with the Bliesmühle still an active grinding operation. Other mills, such as in Mimbach, Gersheim or East Melbourne, were transformed to hydropower production. Frequently, however remember today only ruins of the former mills.
At the assemblies are available on the German side still seven former mills with water storage facilities, that is, across the waters built- String weirs that had the sense to dam up the water to have at low water evenly hydropower available. These transverse structures also led to the first serious encroachment on the river bed and river course: the water was dammed and thus prevented the natural sediment transport of the water. For waters upstream migratory aquatic organisms ( eg fish ) created insurmountable obstacles.
Rafting
Until the 19th century, rafting on the Assemblies operated. The current coming from the Palatinate Forest Schwarzenbach was Flossbar The entire length of the assemblies from the mouth of Black creek. The rafters brought the stricken timber to Saarbrücken, where the smaller rafts met from other tributaries and there - was saar down, floated over the Moselle and the Rhine to Holland - in larger units. They spoke at the assemblies then the Dutch wood, which in shipbuilding took particular use. Through the mill weirs in the Assemblies rafting was hampered. Rafter and Müller therefore had to arrange. While the wood was brought through openings in the weir downstream waters, the mill was missing under circumstances the water to drive the mill wheel, which is why the rafters had to pay to the miller compensation, the so-called closing money ( lock money).
Expansion history
Over Mills changed the culture of the past decades the hydraulic river bed. The total length of the assemblies was reduced from 120 km to nearly 100 km (ie 17% ) with a correspondingly higher gradient. In the first phase, the thirties of the 20th century, the Reich Labor Service straightened the assemblies, for example, in Neunkirchen. Later, the water management administration shortened - mostly to pressure from agriculture - meanders, secured the shore covered with stones and distant trees, especially between Oberthal and Blieskastel 1960-1985.
Protection and development of habitats
The assemblies and parts of their floodplains between Limbach and clean home were reported as a European protected area under the Habitats Directive and the Bliesgau part of the European network of protected areas Natura 2000. Has been recognized by the UNESCO as a Biosphere Reserve by German in May 2009.
As measures for natural water management and development are broken among other things stabilized bank, redesigned and planted, riverbeds structured and protected wetlands from further development, so at Wörschweiler and Ingweiler. Ladders for migratory species such as the brown trout are still pending.
Fauna
After the construction of wastewater treatment plants, especially in the upper reaches of the river and its upper tributaries, the water quality has improved significantly. On the water quality map of the Saarland, the Assemblies 2010 is fully marked as unproblematic. You can meet are mainly the brown trout ( Salmo trutta forma fario ), the bullhead ( Cottus gobio ), minnow ( Phoxinus phoxinus ) and stone loach ( Barbatula barbatula ), grayling, carp, sturgeon, catfish, pike, walleye, nase, barbel, roach, rudd, bream, tailor, moderlieschen, crayfish, chub, perch.
At the assemblies were settled at the beginning of the 21st century beaver again.
Vegetation
By nature, the Bliesauen were predominantly forested. The tree and shrub species have a different tolerance towards the recurrent floods. With the cultivation of the fertile valleys, the alluvial forests were cleared a few remnants and converted into meadows, fields or pastures. This created a mosaic of different habitats. In the assemblies even though water plants come as bur-reed and Comb pondweed before ( Potamogeton pectinatus ), but they are found predominantly in slow-flowing sections, eg Niederbexbach. Typical of many aquatic plants is flooding, that is, the plants form in the flow of vapors, such as the hook - water star ( Callitriche hamulata ), which can for example be found in the assemblies at Bliesbruck.
In the zone of fluctuating water the assemblies no continuous reed belts (eg Phalaris arundinacea L. reed canary grass ) is formed, mainly because of the shade from riparian woodlands and the attachment of bank margins. In particular, below Blieskastel the assemblies is accompanied by a close to nature and Ufergehölzsaum, typically with black alder and various willow species.
The floodplain meadows are used as oat grass meadow pronounced at the lower Assemblies partially. Kümmelblättrigen with the rare hair strand, which occurs in Germany, especially in the Moselle area The Common Nettle Silk happens a parasitic mainly on nettles Art
Infrastructure
Railway lines
In 1857, the railway line Homburg -Zweibrücken was opened, which follows the course of the Assemblies of Homburg Schwarzenacker. 1878 was followed by the Assemblies Valley Railway Zweibrücken - Sarreguemines. Both routes have been shut down.
Leisure
In the valley of the Assemblies of tourism is not well developed. There are few cycling or hiking trails along the river especially on former railway lines, such as on the Assemblies Valley Railway between Blieskastel and clean home and on the railway line St. Wendel Tholey. Both the Saarland bike path as well as the Glan- Blew - cycle path ( Staudernheim - Sarreguemines ) run in the bottom Bliestal. The assemblies suitable for canoeing; only under conservation section of Blieskastel to Bliesdalheim ( river km 36.5 to 27.7 ) to drive through in time is prohibited from 15 April to 15 July.