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Automatically ice-free with blower air after 160 years The Schwarzach Canal Bridge

When it opened in 1846, the King Ludwig I of enthusias- is a masterpiece of civil engineer- tically sought to realize an ancient ing. A 25 mile stretch of the canal - (Ludwig) Canal plan of connecting the Danube between Beilngries and was an ambitious engineer- and Main rivers with the Black Sea is maintained in virtually its original ing project intended to put the and North Sea in order to expand condition by the later city’s munici- shipping networks in Europe. He pal water authority. recently founded Kingdom of also had ulterior motives, however: Two of the most imposing architec- Bavaria on the map as a mod- to forge a stronger bond between tural monuments along the Lud- Bavaria proper and the parts of ern industrial power. Over its wigs Canal are located 15 miles that had been given to south of the Nuremberg city center. length of 107 miles, 100 locks Bavaria by (against the There is the large canal bridge or are employed along the canal will of the inhabitants) as part of aqueduct above the Schwarzach his political restructuring of Europe. to equalize elevation gains up gorge located directly adjacent to The crossing of the Franconian the Feucht rest stop along the A9 to 600 feet through the Jura Jura between Neumarkt in the Up- autobahn, and the smaller Gugel- region of Franconia. per and Schwarzenbruck

Kaeser Compressors, Inc. www.us.kaeser.com hammer canal bridge crossing the Gauchbach stream in Röthenbach, near St. Wolfgang. The Schwarzach canal bridge is not a bridge over the canal, but rather is actually a vaulted sandstone bridge at a height of 58 feet that allows the canal itself to cross the Schwarzach gorge. A true engi- neering marvel, the massive aque- duct is 295 feet long, with an arch spanning 48 feet. Although it was finished as early as 1841, it had to be partially rebuilt soon afterwards due to stability concerns. During the rebuilding, court archi- tect Leo von Klenze left the arch of the bridge largely hollow but fitted it with strong iron tension rods to act as “internal buttresses” to support the pointed arches, themselves built to support the trough above, which contains the water of the canal. This is why the interior of the south arch contains six pointed arches, making it resemble a gothic church. The Schwarzach canal bridge was finally finished in 1844.

Three years ago it underwent a The Kaeser rotary blower will now prevent the water in the aque- general restoration, including ma- duct from freezing, even in harsh winters like that of 1981-82 sonry improvements and resealing, to ensure its stability for the next (bottom photo; the beginning of the canal 171 years. bridge can be seen in the background, near the railing walls) Because it contains a body of wa- ter, the historic canal bridge would be structurally devastated if allowed to freeze solid. Breaking up the ice has traditionally meant strenu- ous manual labor – until now. The Nuremburg Water Authority recently installed a Kaeser DB 166 rotary blower in an inconspicuous wooden hut on the east bank of the canal, By: Klaus Dieter Bätz south of the canal bridge. Auto- matically activated in the event of freezing temperatures, the blower Getting to the Schwarzach canal bridge... drives air at low pressure through a ...is straightforward for anyone driving either north or south on the A9 autobahn. perforated hose laid along the canal Simply leave the autobahn at the exit marked “Feucht” off the Feucht floor on both sides. The air bubbles autobahn junction, then take the B8 towards “Neumarkt i. d. Opf.” (Neumarkt agitate the water, reliably prevent- in the ). Turn right at the first light. When the road turns to the ing ice formation. left, take the second paved forest road – it leads directly to the canal bridge. The parking lot at the inn (“Zum Ludwigskanal”) is an ideal starting point for exploring a section of the Ludwig Canal. Two locks can be seen along the canal, just over 500 yards to the south. The second features one of the 69 cabins for the lock keepers, whose responsibilities went beyond operating and maintaining three locks each – they were also tasked with harvesting and selling the fruit from the 40,000 fruit trees planted along the canal (apple, pear, cherry and plum).

Kaeser Compressors, Inc. www.us.kaeser.com