A body of water, such as a
river,
canal or
lake, is navigable if it is deep, wide and slow enough for a
vessel to pass and there are no obstructions, like
rocks,
trees and low
bridges. Shallow rivers may be made navigable by the installation of
locks that increase and regulate water depth, or by
dredging. A very high water speed may also make a
channel unnavigable and high-
latitude waters may be unnavigable in winter because of
freezing. Navigability also depends on the size of the vessel: A small river may not be navigable by a
freighter, but it might be navigable by a smaller craft, like a
motor boat or
kayak. Therefore, whether a water body is considered navigable or unnavigable depends on the context.
In the United States
Navigable waters of the
United States, as defined in 33 CFR 329, are those waters that are subject to the ebb and flow of the tide and/or are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce while the waterway is in its ordinary condition. Section 10 of the
Rivers and Harbors Act of 1899 (33 U.S.C. 403), approved 3 March 1899, prohibits the unauthorized obstruction of a navigable water of the U.S. This statute also requires a permit from the
U.S. Army Corps of Engineers for any construction in or over any navigable water, or the excavation or discharge of material into such water, or the accomplishment of any other work affecting the course, location, condition, or capacity of such waters.
Also, the Clean Water Act use the term "navigable waters," "navigable waters of the United States" and "navigablity." These terms are dependent on judicial interpretation and are somewhat more flexible currently, in light of a U.S. Supreme Court decision on two joined cases: "Carabell v. United States" and "Rapanos vs. United States.
Inland water transport systems
Inland Water Transport (IWT) Systems have been used since prehistoric times in countries like
India,
China and
Egypt.
In modern times, the Netherlands, the United States, Germany, China, Bangladesh and India have developed significant IWT systems. For example, in the Netherlands, IWT handles 46% of the nation's inland freight; 32% for Bangladesh 32%, 14% in the United States, and 9% in China.
Inland water transport system in India
In India there are currently three National Waterways totaling a distance of 2921 km. They are:
It is estimated that the total navigable length of inland waterways is 14500 km. A total of 16 million tonnes of freight is moved by this mode of transport.
Advantages of inland water transport systems
Waterways provide enormous advantages as a mode of transport compared to land and air modes of transports.
- Cheaper capital cost - Nature has already done the initial engineering work for the transportation infrastructure. Thanks to this gift of nature, the cost of developing an inland waterway is 5-10% of the cost developing an equivalent railway or a 4-lane expressway.
- Cheaper maintenance cost - The maintenance cost of an inland waterway is only 20% of the maintenance cost of an equivalent roadway.
- Greater fuel efficiency (low cost of transportation) - It is estimated that 1 liter of fuel can move 105 ton-km by inland water transport. Whereas the same amount of fuel can move only 85 ton-km by rail and 24 ton-km by road. By air, its even less.
- Easy integration with sea transport - Inland water transport can easily integrated with Sea transport and hence it reduces the extra cost required for land-sea or air-sea transport interface infrastructure development. It also reduces the time taken to transfer the goods to-n-from sea transport vessels.
Disadvantages of inland water transport systems
- Low availability of inland waterways - As mentioned above, there are numerous criteria for a water body to be navigable. Out of the total inland water body available in the world, only very low percent of it is potentially navigable.
- Low speed - Water transport as a whole is much slower than its road, rail, or air competitors.
References