Alb (High Rhine)

This article is about the river in the southern Black Forest. For the river of the same name in northern Black Forest, seeAlb (Upper Rhine). For other uses, seeALB (disambiguation).

Not to be confused with the mountain rangeSwabian Alb.

TheAlb (also:Hauensteiner Alb) is a river in the southernBlack Forest. It arises from twoheadwaters, theMenzenschwander Alb andBernauer Alb, and flows in a southerly direction. It ends after 43.6 kilometres (27.1 mi) (includingMenzenschwander Alb) at a confluence with theHigh Rhine at Albbruck.

Alb
View from Spießhorn eastward into Menzenschwander Alb valley
Location of mouth
Location
Country	Germany
Location	Black Forest
Physical characteristics

Source
• location	Menzenschwander Alb
• coordinates	47°51′42″N8°1′37″E / 47.86167°N 8.02694°E /47.86167; 8.02694
• elevation	1,347 m (4,419 ft)

Mouth
• location	Confluence withHigh Rhine atAlbbruck
• coordinates	47°35′3″N8°7′43″E / 47.58417°N 8.12861°E /47.58417; 8.12861
• elevation	308 m (1,010 ft)
Length	43.6 km (27.1 mi)^[1]
Basin size	243 km² (94 sq mi)^[1]
Basin features
Progression	Rhine→North Sea
Tributaries
• right	Ibach, Höllbach

Etymology

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The nameAlb is possibly derived from aProto-Indo-European word*albhos meaning "white" or perhaps "river".

Headwaters

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The headwaters of the Menzenschwander Alb lie on the southern slope of theFeldberg mountain range in theLandkreis ofBreisgau-Hochschwarzwald. The Bernauer Alb rises on the southern slope of theHerzogenhorn. The Menzenschwander Alb is about 12 kilometres (7 mi) long and flows south-east pastMenzenschwand. The Bernauer Alb is about 11 kilometres (7 mi) long; it also flows south-east, pastBernau. The confluence of the two headwaters is atGlashofsäge, about 4 kilometres (2.5 mi) fromSankt Blasien.

The valleys of both headwaters were widened byglaciers during theice age. Both are about 900 metres (3,000 ft) high and dominated by grassland. The Bernau valley is a broad basin, characterized bymoraines, marshy valleys, ravines, andRoche moutonnées. Thehamlets and isolated farms that make up the valley lie some distance above the frost-prone valley floor.

Theglacial features in the Menzenschwand valley are even more striking. TheMenzenschwander Kluse is a well-knownterminal 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

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The area occupied by the municipality of Sankt Blasien's area is dominated by theclassicist dome of Sankt Blasien'sCathedral. Below the village centre, the Alb form a waterfall, locally known asWasserfall am Tusculum, after the Roman town ofTusculum. 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 bytectonic movements of the Earth'scrust, which have increased thegradient to theHigh Rhine. The only valley that continues in a south-eastern direction is about 200 metres (660 ft) higher, in the saddle nearHäusern. During the ice age, the Alb glacier was about 300 metres (980 ft) high in this area, and its meltwater overflowed the Häusern saddle, into theSchwarza valley.

Below this bend, the Alb water is collected in areservoir, theAlb Basin. Its average surface area is 18 hectares (44 acres); it is impounded by a dam of about 80 metres (260 ft) in length. Most of the water is piped to theSchwarzabruck reservoir. Both reservoirs are owned by theSchluchseewerk AG.

The Alb then flows through a 200-to-400-metre (660 to 1,310 ft) 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 undulatingHotzenwald plateau in the municipalities ofDachsberg undHöchenschwand. The plateau is indented by bogs and rocky hilltops.

During theWürm ice age, the Alb glacier ended at the point where we now find the village ofNiedermühle. With a length of 27 kilometres (17 mi), 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

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Teufelsküche, a giant's kettle in the Alb valley

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 theTeufelsküche ("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 80 metres (260 ft) higher, on the left bank. On a wider spot in the valley, is the saw millTiefenstein 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 4 kilometres (2.5 mi) downstream of Tiefenstein. Long ago, the Alb followed a different course and flowed toHauenstein 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 ofwhitewater in Germany.^[2] In this section the road runs up to 100 metres (330 ft) above the river and passes through five short tunnels drilled through the cliffs, giving it the nickname "Axenstraße of the Black Forest". From the hamletHohenfels, the road descends to the valley floor atAlbbruck, where the Alb flows into the High Rhine.