Alb (Southern Black Forest)

The Alb (also: ''Hauensteiner Alb'') is a river in the southern Black Forest. It arises from two headwaters, the Menzenschwander Alb and Bernauer Alb, and flows in a southerly direction. It ends after (including ''Menzenschwander Alb'') at a confluence with the High Rhine at Albbruck.

Etymology

The name ''Alb'' is possibly derived from a Proto-Indo-European word ''*albhos'' meaning "white" or perhaps "river".

Headwaters

The headwaters of the Menzenschwander Alb lie on the southern slope of the Feldberg mountain range in the Landkreis of Breisgau-Hochschwarzwald. The Bernauer Alb rises on the southern slope of the Herzogenhorn. The Menzenschwander Alb is about long and flows south-east past Menzenschwand. The Bernauer Alb is about long; it also flows south-east, past Bernau. The confluence of the two headwaters is at ''Glashofsäge'', about from Sankt Blasien.

The valleys of both headwaters were widened by glaciers during the ice age. Both are about high and dominated by grassland. The Bernau valley is a broad basin, characterized by moraines, marshy valleys, ravines, and Roche moutonnées. The hamlets and isolated farms that make up the valley lie some distance above the frost-prone valley floor.

The glacial features in the Menzenschwand valley are even more striking. The ''Menzenschwander Kluse'' is a well-known terminal moraine. Below the Kluse, the Menzenschwand Alb plunges with several waterfalls through a small ravine to a basin created by the former Krunkelbach valley glacier.

Middle reaches

The area occupied by the municipality of Sankt Blasien's area is dominated by the classicist dome of Sankt Blasien's Cathedral. Below the village centre, the Alb form a waterfall, locally known as , after the Roman town of Tusculum. The Alb, like most rivers in this part of the Black Forest, then changes its course by about 60 degrees, towards the south. This is thought to be caused by tectonic movements of the Earth's crust, which have increased the gradient to the High Rhine. The only valley that continues in a south-eastern direction is about higher, in the saddle near Häusern. During the ice age, the Alb glacier was about high in this area, and its meltwater overflowed the Häusern saddle, into the Schwarza valley.

Below this bend, the Alb water is collected in a reservoir, the Alb Basin. Its average surface area is ; it is impounded by a dam of about in length. Most of the water is piped to the '' Schwarzabruck'' reservoir. Both reservoirs are owned by the Schluchseewerk AG.

The Alb then flows through a wide valley, lined by meadows, which contains the villages of Schlageter and Immeneich. The valley is no longer bordered by narrow, wooded ridges, but instead by the undulating Hotzenwald plateau in the municipalities of Dachsberg und Höchenschwand. The plateau is indented by bogs and rocky hilltops.

During the Würm ice age, the Alb glacier ended at the point where we now find the village of ''Niedermühle''. With a length of , the Alb glacier was the longest in the Black Forest. Downstream of Niedermühle, the valley is very narrow, leaving no room for settlements.

Alb Gorge

The slope of the Alps increased greatly in the ravines and the river forces its way through the more canyon-like passages and blocked sections known as the ("Devil's Kitchen"). The Ibach and Höllbach join from the right, each emerging from its own narrow gorge. The Höllbach has two waterfalls in this area. Because the gorge is so narrow, the road is up to higher, on the left bank. On a wider spot in the valley, is the saw mill ''Tiefenstein'' and two tributaries, Schildbach and Steinbach. Halfway up the slope, there are granite quarries and the ruins of two castles.

The narrowest and most dangerous passage begins downstream of Tiefenstein. Long ago, the Alb followed a different course and flowed to Hauenstein through the valley now occupied by the Mühlbach. This route was blocked by glacial deposits during an earlier ice age, forcing the Alb to find a new route to the Rhine. Since then, the "new" gorge cuts through the granite rock. This section cannot be travelled without special equipment, even though the water flow is usually low, because most of the water has been diverted. It there is sufficient water, canoeing is possible, although this is considered the most difficult stretch of whitewater in Germany.Josef Haas: ''Wildwasserperlen'', Constance, 1980, p. 25 In this section the road runs up to above the river and passes through five short tunnels drilled through the cliffs, giving it the nickname "Axenstraße of the Black Forest". From the hamlet ''Hohenfels'', the road descends to the valley floor at Albbruck, where the Alb flows into the High Rhine.

Gallery

File: Menzenschwand 7688.jpg , Waterfalls in the gorge of Menzenschwander Alb
File: Herzogenhorn in Richtung Bernau.jpg , The valley north of Bernauer Alb
File: St Blasien 1900.jpg , St Blaise and the upper Alb valley in 1900
File: StBlasienFluss.jpg , The Alb in St. Blasien
File: AlbStausee.jpg , The Albbecken below St. Blasien
File: AlbNiedermuehle.jpg , The Alb valley above the gorge at ''Niedermühle''
File: AlbTiefenstein.jpg , Widening of the Alb gorge at Tiefenstein
File: Albtaltunnel.jpg , One of the five tunnels in the upper canyon wall

See also

* Alb (Northern Black Forest)

Footnotes

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Rivers of Baden-Württemberg
Rivers of the Black Forest
Rivers of Germany