In August 2022 we visited Poland for the first time. On our last day, a beautiful sunny Sunday afternoon, we were treated to a boat ride on the Elblag Canal. Not only was it a pleasant and relaxing excursion, it opened my eyes to an engineering
invention I had not seen before. I had to learn more about this; what I learned follows.
History
The Elblag Canal was commissioned by the King of Prussia and then designed between 1825 and 1844 by Georg Steenke. Construction began in 1844 and was completed in 1860 (Wikipedia) or 1872 (Brittanica). As it was built during a time of Prussian control, it was referred to as the Elbing or Oberleandischer (Upland) Canal. As of 1945 it came under Poland. After damage from World War II was repaired, it was restored to operation in 1948 and is now used for tourism. The canal underwent further renovation between 2011 and 2015 and is now again open to navigation.
Location
The Canal was built to run southward from Lake Drużno (top blue marker in map at left), connected by the river Elbląg to the Vistula Lagoon (large body of water at top of map) off the Baltic Sea in the north, to the river Drwęca, Lake Jeziorak and the inland port of Ostroda in the southeast (starred marker at bottom right hand corner of map). The four central starred markers indicate the region of the inclined planes (see explanation below).
According to Wikipedia it is 80.5 km or 50 miles long. The article on Elblag City in Encyclopedia Brittanica lists it as 159 km or 99 miles, that on Elblag Province as 56 km or 35 miles.
Engineering
The difference in water levels approaches 100 metres (330 ft), and is overcome using locks and a system of inclined planes between lakes. The latter were were deemed necessary as it was assessed that the difference in height over a 9.5-kilometre (5.9-mile) section of the route between the lakes was too great for building traditional locks. These were based on those used on the Morris Canal, built in the US between 1829 and 1924, linking Easton, Pennsylvania and Newark, New Jersey. Big Chute Marine Railway, at lock 44 of the Trent-Severn Waterway in Ontario, Canada, also carries boats in an open carriage instead of a water filled caisson. There were originally four inclined planes, with a fifth added later, replacing five wooden locks. The canal does include a few locks as well.
The Inclined Planes
The four original inclined planes are, in order from the summit level downwards, Buczyniec (Buchwalde) with a rise of 20.4 metres (67 ft) and a length of 224.8 metres (738 ft), Kąty (Kanthen) with a rise of 18.83 metres (61.8 ft) and a length of 225.97 metres (741.4 ft), Oleśnica (Schönfeld) with a rise of 21.97 metres (72.1 ft) and a length of 262.63 metres (861.6 ft), and Jelenie (Hirschfeld) with a rise of 21.97 metres (72.1 ft) and a length of 263.63 metres (864.9 ft).[3] The fifth incline is Całuny Nowe (Neu-Kussfeld) with a rise of 13.72 metres (45.0 ft). It was built to replace five wooden locks close to Elbląg. They were constructed from 1860 to 1880. The inclines all consist of two parallel rail tracks with a gauge of 3.27 metres (10 ft 8+3⁄4 in). Boats are carried on carriages that run on these rails. The inclines each rise from the lower level of the canal to a summit and then down a second shorter incline to the upper canal level. The first part of the main incline and the short upper incline were both built at a gradient of 1:24 (4.2%). A carriage is lowered down the incline between the sections of canal to counterbalance an upward moving carriage. Once the downward moving carriage has reached the summit, pulled up by a system of cables, and started down the main incline its weight helps pull up the upward moving carriage. This allowed the slope of the incline for this section to be built at a steeper gradient of 1:12 (8.3%).
The whole system is ingeniously based on energy conserving water power. It seems that when they need to move the carriages, a signal goes to a control room. There, they let water from the canal out a sluice, which turns a large wheel which in turn through a system of gears pulls the cables which pull the carriages up and down the inclined planes. The weight of a boat on a carriage going down acts as a counter via the single cable system for each inclined plane to pull another wagon up. The water from the water wheel runs down side channels and back into the canal at a lower level.
The canal was built to accommodate small vessels up to 50 tonnes (49 long tons; 55 short tons) displacement. The boats had a maximum length of 24.48 metres (80 ft 4 in), a maximum width of 2.98 metres (9 ft 9 in) and a maximum draught of 1.1 metres (3 ft 7 in).
Significance
Today the canal is used mainly for recreational purposes. It is considered one of the most significant monuments related to the history of technology and was named one of the Seven Wonders of Poland*. The canal was also named one of Poland's official national Historic Monuments in 2011. Its listing is maintained by the National Heritage Board of Poland. It is believed to be one of the most important monuments related to the history of engineering.
* (in Polish) As per results of a plebiscite for the 'Seven Wonders of Poland' conducted by Rzeczpospolita (newspaper), cited at www.budowle.pl.
Sources:
https://en.wikipedia.org/wiki/Elbląg_Canal
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