James S. Aber
|Central U.S.||Eastern U.S.|
|Erie Canal||Swedish canal|
|Polish canals||German canals|
Canals and navigable rivers are subject to the same "laws of nature" that govern uncontrolled streams. Water flow, sediment erosion, flooding, transport of pollutants, and related issues are of great importance for long-term maintenance and operation of canals. Canals also have special circumstances, as they often require dedicated water sources, and they may connect drainage basins of dissimilar type. Migration of "exotic" aquatic species has occurred in some canals.
The following examples display canals and navigable rivers from North America and Europe. Some are largely for irrigation, some for commercial shipping, and others for pleasure cruising. Click on each thumbnail image to see the full-sized version. All images © by the author.
Western United States and Mexico
Many portions of the western United States are semi-arid to arid. These areas lack sufficient
water for agriculture. In some regions it is possible to import water via canals from rivers
draining the Rocky Mountains. Examples are presented below from California, Colorado and Nebraska.
|Imperial Valley, southern California and northern Mexico. False-color satellite image, in which active vegetation appears red and pink. The All American Canal enters right side of scene and flows westward just north of the U.S.-Mexican border. This is the "last tap" from the Colorado River on the U.S. side of the border. Bright red irrigated cropland is evident in the Imperial Valley of the United States, but crops have less irrigation water in Mexico. Image from NASA GSFC.|
|San Luis Valley, Colorado: water is pumped from shallow wells into the head of a canal. This water is shipped to New Mexico to satisfy interstate water obligations. Image date 10/06, © J.S. Aber.|
|Canal in the San Luis Valley of south-central Colorado. Ground water "salvaged" from high-capacity wells is transported southward to the Rio Grande for use in New Mexico. Image date 3/02, © J.S. Aber.|
|Sand Hills, near Valentine, Nebraska. A concrete-lined irrigation canal brings water from Merritt Reservoir on the Niobrara River. Water in the Niobrara River is supported by baseflow from the High Plains (Ogallala) aquifer of central Nebraska. Photo date 6/97, © J.S. Aber.|
|Central United States|
The central United States generally have abundant surface water, and there is little irrigation. Navigable rivers are maintained primarily for shipping. A large volume of barge traffic plies up and down the Mississippi and Ohio rivers, and a lesser volume moves on the lower Missouri. Agricultural produce (mainly grain) moves downstream, and petroleum products are transported upstream. Between Minneapolis and St. Louis, the Mississippi is controlled by a series of low dams and locks to facilitate this transportation system.
|Lock and dam 15 on the Mississippi River at Rock Island, Illinois. Two side-by-side locks may operate simultaneously for traffic moving in either direction. Photo date 8/98, © J.S. Aber.|
|String of grain barges, 3 wide and 4 long, entering lock 15 from upstream end. Photo date 8/98, © J.S. Aber.|
|Towboat Crimson Glory pushes barges out of lock 15 (downstream). The barge immediately in front of the towboat carries diesel fuel. Bridge has rotated to side to allow passage of the towboat. Photo date 8/98, © J.S. Aber.|
Eastern United States and Canada
The eastern United States and Canada generally have abundant surface water, and there is
little irrigation. Canals are maintained primarily for shipping. Access to the Great Lakes
is provided via the Welland Canal (Ontario) for ocean-going ships, and many other canals are
utilized for smaller ships and pleasure craft.
|Niagara River, New York and Ontario. False-color satellite image, in which active vegetation appears red and pink. Lake Ontario, in upper left corner, and Lake Erie, scene bottom, are connected by the Niagara River (scene center). Niagara Falls represents a major barrier to navigation between the Great Lakes and the Atlantic. The main connection across Ontario is the Welland Canal, visible near left side of scene. The New York State Barge Canal (NYSBC) is depicted in the upper right part of the scene. The Welland is the prinicpal commercial shipping route, whereas the NYSBC is now used mainly for pleasure craft. Image from NASA GSFC.|
|Old Erie Canal|
The old Erie Canal was the first major water-works project in the United States, built in 1817-1825. It proved the practicality of large-scale water diversions without upsetting the environment. The canal connected Lake Erie to the New York harbor tidewater in a multi-level route that followed the local terrain and was fed by local water sources. The original canal was 40 feet wide and 4 feet deep, 363 miles long, and had 81 locks. Water flow in the canal was required for several purposes (Langbein 1976).
|Remnant of the Chenango Canal near Hamilton, New York. It connected the Erie Canal near Oneida to the Susquehanna River at Binghamton in south-central New York. The canal follows the Chenango River valley for most of its route. Photo date 7/77, © J.S. Aber.|
|Old stone lock on the Chenango Canal near Binghamton, New York. The canal was abandoned long ago, and most portions are dry or have been removed. The old stone lock remains as a relict of this short-lived canal. Photo date 7/77, © J.S. Aber.|
The Erie canal was enlarged twice: 1836-1862 and 1905-1917. It is now known as the New York State Barge Canal (NYSBC; see above), which is used today mainly for recreation.
western New York. Photo date 3/08 ©, J.S. Aber.
|In older times, the entrance to the Baltic Sea was controlled by the Danish Kingdom, and tolls collected from passing ships were an important source of royal revenue. In order to avoid this expense, a canal was constructed across southern Sweden from Göteborg (near map center), via large lake basins, to the eastern coast. An industrial center grew up at Trollhättan based on the canal and water power. Map taken from Hippocrene Atlas of Europe (1985/86).|
|Locks at Trollhättan, Sweden. Three generations of locks have been constructed at Trollhättan. In this view, older locks appear to left and the modern lock is visible to right. Photo date 6/93, © J.S. Aber.|
|A pleasure yacht emerges from the lower (downstream) side of a canal lock at Trollhättan. Note the great height of the lock sides. Photo date 6/93, © J.S. Aber.|
|A ship loaded with timber emerges from the upper side of a canal lock at Trollhättan. Photo date 3/87, © J.S. Aber.|
Canals of Poland
The Baltic region of northern Poland has several canal systems. In places, these canals
utilize natural glacial lakes, rivers, and valleys. In other places, the canals cross
upland areas in order to connect different drainage basins. The origins, purposes, and
current uses of these canals bear witness to the complicated history of Poland during the
past two centuries.
|Map of northeastern Poland. Various canal systems connect lakes and rivers to tidewater. From Polska Mapa Fizyczna (1988).|
The Augustów Canal was conceived as a result of the partition of Poland, when Prussia (Germany) gained control of the lower Vistula River. Prussian customs duties effectively closed trade to the Baltic seaports. The canal was built as a waterway to bypass Prussia. The canal route joins the Vistula to the Nieman River in what is now Byelarus with downstream outlet to the Baltic. A network of regulated rivers and lakes was utilized with canal links at Augustów. Construction began in 1825 and after some interruption was completed in 1839. The canal was quite active during its first 20 years, but thereafter lost its economic significance. Today it is used mainly for touristic purposes, and since 1968 has been protected as a monument to early industrial water transport and engineering (Gielzynski et al. 1994).
|Map of the Augustów canal, just right of map center. The canal provides a link between various lakes and rivers in the Mazurian upland region. From Polska Mapa Fizyczna (1988).|
|Canal lock at Augustów. The lock joins the canal to a lake (in background). Photo date 9/93, © J.S. Aber.|
|Lake/canal tour boats at Augustów. These tourist boats travel the lakes and canal in northeastern Poland. Photo date 9/93, © J.S. Aber.|
The Elblag canal connects the Vistula estuary at tidewater with Ostróda in the Mazurian upland lake district. This canal was constructed under the Prussian regime during the period 1845-60 (Gielzynski et al. 1994). It begins at the city of Elblag and extends southward through the low delta region, then ascends into the Mazurian upland, where it follows a series of lakes belonging to the Illawa chain, to the city of Ostróda. The canal has an unusual means for transporting boats from one level to another. The canal is utilized today mainly by tourists.
|Map of the Gdansk-Elblag region of northern Poland. The Elblag Canal begins at tidewater in the Vistula estuary (Zalew Wislany). It extends through Lake Druzno just south of Elblag. This lake was open to the Vistula estuary during the Middle Ages, but the connection later dried up. From Polska Mapa Fizyczna (1988).|
|City of Elblag, northern Poland. This is the tidewater beginning for the Elblag Canal in the Vistula estuary. Photo date 9/93, © J.S. Aber.|
|Elblag Canal employs a unique mechanical means for lifting boats from one level to another. Boats are carried on "cable cars" that move up/down the ramp. The cable is pulled around the large wheel that can be seen in the canal at the bottom of the ramp. Photo date 7/93, © J.S. Aber.|
|Cable car at top of ramp is entering upper canal segment, where the boats will be released. Photo date 7/93, © J.S. Aber.|
|Power for the cable car system is supplied by a water wheel, which harnesses the difference in elevation between upper and lower canal segments. Only hydropower is necessary to run the cable cars, which results in quiet, low-cost operation. Photo date 7/93, © J.S. Aber.|
German Canals and Rivers
Germany is the industrial heartland of northern Europe. Navigable rivers and canals link
all major cities to each other and with adjacent seas--Baltic and North. As in other parts
of western Europe, self-propelled barges are the primary means for shipping freight and bulk
goods. Small pleasure craft and tourist boats are extremely common also on these waterways.
|Map of northern Germany. The Rhine River in western Germany is a major international waterway that extends to the North Sea. It is linked via a network of canals that follow glacial valleys across the country to the north and east to the Baltic Sea and the Odra River on the German-Polish border.|
|Barges on the Rhine River at Andernach, Germany. Two loaded barges are moving upstream. The control house and living quarters are located at the stern of the barge. Photo date 8/95, © J.S. Aber.|
|Unloading hops on the Rhine River at Andernach, Germany. The barge is nearly empty, as shown by its position in the water. Photo date 8/95, © J.S. Aber.|
The Eberswalde Gap is a natural opening in the upland of eastern Germany to the Odra lowland along the German-Polish border. This gap is the location of a "ship lift" at Niederfinow. The ship lift is the only one of its kind in the world. It connects an old channel of the Odra River at 2 m above sealevel to a canal in the "gap" at 36 m above sealevel. The lift is essentially an "elevator" that raises/lowers ships in a water tub. Huge counter weights balance the lift, which is run by electric motors. This ship lift was considered so important, that is was not destroyed during World War II.
|Map of eastern Germany and western Poland. The ship lift at Eberswalde is located northeast of Berlin. From Polska Mapa Fizyczna (1988).|
|Ship lift at Niederfinow, eastern Germany. The lift is an "elevator" for fully loaded barges and ships. It changes level by 32 m (105 feet). Photo date 8/95, © J.S. Aber.|
|View of the lower entrance to the lift, as seen from the top of the lift. A barge is waiting its turn to move into the lift. Photo date 8/95, © J.S. Aber.|
|Front end of barge moving into the lift. This view is straight down from the top of the lift. Photo date 8/95, © J.S. Aber.|
|Lift coming up, as seen from the top of the lift. A portion of a barge (green) and a smaller sail boat can be seen in the lift (bottom of view). The upper canal level is visible at top of view. Photo date 8/95, © J.S. Aber.|
|Barge emerging from upper level of lift and entering the canal. Photo date 8/95, © J.S. Aber.|
|Barge moving away from the lift into canal, headed toward Berlin. This barge is based in Bydgoszcz, Poland. Structure in background is an emergency gate that can be closed in event of an accident or failure on the lift. Photo date 8/95, © J.S. Aber.|
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