1. Accommodation Boat (AB)/ Barrack ship

A ship containing a superstructure of a type suitable for use as a temporary accommodation for sailors.

Accommodation Boat Glossary

2. Bandalling and Bandals

Bandalling system has been developed locally in the Indian subcontinent for the improvement of channel navigability. Bandal may simply be described as a vertical screen mounted on a frame and can be placed on either sides of a channel that are required to be improved. They concentrate the flow into the channel, the velocity of the flow is increased, which results scouring of the channel.

Bandalling and Bandals Glossary

3. Barge

A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Some barges are not self-propelled and need to be towed or pushed by towboats.

Barge Glossary

4. Barrage

A barrage is a type of low-head, diversion dam which consists of a number of large gates that can be opened or closed to control the amount of water passing through the structure, and thus regulate and stabilize river water elevation upstream for use.

Barrage Glossary

5. Braiding

A channel that consists of a network of small channels separated by small and often temporary islands called braid bars. Braided streams occur in rivers with high slope and/or large sediment load.

Braiding Glossary

6. Buoys

A buoy is a floating device that can have many purposes. It can be anchored (stationary) or allowed to drift with the sea wave.

Buoys Glossary
6.1 Lifebuoy

Used as a lifesaving buoy designed to be thrown to a person in the water to provide buoyancy.

6.2 Submarine communication buoys

Used for release in case of emergencies or for communication.

6.3 DAN buoy

A large maritime navigational aid providing a platform for light and radio beacons.

6.4 Sonobuoy

used by anti-submarine warfare aircraft to detect submarines by SONAR.

6.5 Surface marker buoy

taken on dives by scuba divers to mark their position underwater.

6.6 Tripping buoys

A navigational buoy which marks the entrance to a channel or a nearby landfall.

6.7 Tripping buoys

used to keep one end of a 'tripping line' on the water's surface so that a stuck anchor

6.8 Mooring buoys

used to keep one end of a 'tripping line' on the water's surface so that a stuck anchor

6.9 Weather buoys

equipped to measure weather parameters such as air temperature, barometric pressure, wind speed and direction and to report these data via satellite radio links such as the purpose-built Argos System or commercial satellite phone networks to meteorological centres for use in forecasting and climate study. May be anchored (moored buoys) or allowed to drift (drifting buoys) in the open ocean currents. Position is calculated by the satellite.

6.10 Tsunami buoys

Anchored buoys that can detect sudden changes in undersea water pressure are used as part of tsunami warning systems in the Pacific Tsunami Warning Center and Indian Oceans.

6.11 Ice marking buoys

Used for marking ice holes in frozen lakes and rivers, so that snowmobiles do not drive over the holes.

6.12 Marker buoys

Used in naval warfare, particularly anti-submarine warfare, is a light-emitting or smoke-emitting, or both, marker using some kind of pyrotechnic to provide the flare and smoke.

6.13 Wave buoy

Used to measure the movement of the water surface as a wave train.

7. Vessel

Any craft designed for transportation on water, such as a ship or boat. The only difference between a Vessel and a barge is that vessel can be explained as any floating body used for transportation of goods or people but a Barge will always be a large flat bottomed boat used mainly for transportation of cargo or goods. A Barge is always a vessel, but a vessel is not always a Barge

8. Meandering

A meander, in general, is a bend in a river. A meander forms when moving water in a stream erodes the outer banks and widens its valley, and the inner part of the river has less energy and deposits silt. The river erodes sediments from the outside of a bend and deposits them on the inside. The result is a snaking pattern as the stream meanders back and forth across its down-valley axis. River Ganga meanders a lot before reaching Sunderbans.

Meandering Glossary

9. Dredging

Dredging is an excavation activity usually carried out at least partly underwater, in shallow seas or freshwater areas with the purpose of gathering up bottom sediments and disposing of them at a different location. This technique is often used to keep waterways navigable. It is also used as a way to replenish sand on some public beaches, where sand has been lost because of coastal erosion.

10. Dredger

A Dredger is any device, machine, or vessel that is used to excavate and remove material from the bottom of a body of water. For example, a scoop attached to the end of a rope or pole by which an operator can draw sediments up from the bottom of a pond is a dredger. Developing this idea further, a motorized crane equipped with a drag bucket or clamshell (grabber) that is used to scoop material from the bottom of a body of water is also a dredger. The crane could be located on the bank or perhaps mounted on a barge. If the crane is mounted on a barge, the entire vessel is referred to as a dredger. The process of dredging creates spoils (excess material), which are carried away from the dredged area. Dredging can produce materials for land reclamation or other purposes (usually construction-related) and has also historically played a significant role in gold mining. Dredging can create disturbance in aquatic ecosystems.

Dredger Glossary
10.1 Suction Dredger

These operate by sucking through a long tube, like some vacuum cleaners but on a larger scale. A plain suction dredger has no tool at the end of the suction pipe to disturb the material. This is often the most commonly used form of dredging.

10.2 Cutter Suction dredger (CSD)

A cutter-suction dredger's (CSD) suction tube has a cutting mechanism at the suction inlet. The cutting mechanism loosens the bed material and transports it to the suction mouth. The dredged material is usually sucked up by a wear-resistant centrifugal pump and discharged either through a pipeline or to a barge. Cutter-suction dredgers are most often used in geological areas consisting of hard surface materials (for example gravel deposits or surface bedrock) where a standard suction dredger would be ineffective. In recent years, dredgers with more powerful cutters have been built in order to excavate harder rock without the need for blasting.

Cutter Suction dredger Glossary

11. Beacons

A beacon is an intentionally conspicuous device designed to attract attention to a specific location. Beacons help guide navigators to their destinations. Types of navigational beacons include radar reflectors, radio beacons, sonic and visual signals. Visual beacons range from small, single-pile structures to large lighthouses or light stations and can be located on land or on water. Lighted beacons are called lights; unlighted beacons are called day beacons.


12. Jetties

A jetty is a structure that projects from the land out into water. Often, "jetty" refers to a walkway accessing the center of an enclosed waterbody. By directing sediment from the rivers or tidal inlets farther offshore, jetties function to limit the build-up of sediment within the channel. Jetties also serve to form the basins in which vessels lie when discharging and taking in cargoes. Based on the tidal conditions, high level and low level jetties are constructed.

Jetties Glossary

13. Shoal

A shoal, sandbank, sandbar (or just bar in context), or gravel bar, is a characteristically linear landform completely within or extending into a body of water. It is typically composed of sand, silt, and/or small pebbles. Shoals are characteristically long and narrow (linear) and develop where a stream, river, or ocean current promotes deposition of sediment and granular material, resulting in localized shallowing (shoaling) of the water.

14. LAD

Least Available depth (LAD) is the minimum depth in river that has to be maintained for safe navigation purpose.

15. Breakwater

Breakwaters are structures constructed on coasts as part of coastal defense or to protect an anchorage from the effects of both weather and longshore drift. Breakwaters, also called bulkheads, reduce the intensity of wave action in inshore waters and thereby reduce coastal erosion or provide safe harborage. Breakwaters may also be small structures designed to protect a gently sloping beach and placed one to three hundred feet offshore in relatively shallow water.


16. Floating terminal

Vessel or barge, operating in open sea, with a considerable storing capacity (up to Capsize) able to discharge barges and concurrently loading Ocean Going Vessels or, alternatively, to store cargo in the holds. NW1 has 20 floating terminals.

Floating terminal Glossary

17. Fairway

The navigable portion of a river, harbor, or other partly enclosed body of water

18. RO-RO

Roll-on/roll-off (RORO or ro-ro) ships are vessels designed to carry wheeled cargo, such as automobiles, trucks, semi-trailer trucks, trailers, and railroad cars, that are driven on and off the ship on their own wheels or using a platform vehicle, such as a self-propelled modular transporter. RORO vessels have built-in ramps that allow the cargo to be efficiently rolled on and off the vessel when in port. Ro-Ro Terminal at Dhubri (NW2) is under construction.

RO-RO Glossary

19. Transshipment

The transshipment of containers at a container port or terminal can be defined as the number (or proportion) of containers of the total container flow that is handled at the port or terminal and, after temporary storage in the stack, transferred to another ship to reach their destinations.

20. Cofferdam

A cofferdam is a temporary enclosure built within, or in pairs across, a body of water and constructed to allow the enclosed area to be pumped out, creating a dry work environment for the major work to proceed.


21. Amphibian Dredger

An amphibious dredger is a type of excavator that can perform dredging while afloat in shallow water. An amphibious dredger is better adapted for removing silty clay, clearing silted trenches, swampland operation and low water area, then traditional ship-mounted dredgers.

Amphibian Dredger Glossary

22. Bathymetric Survey

Bathymetry is the study of underwater depth of lake or ocean floors. Bathymetric (or hydrographic) charts are typically produced to support safety of surface navigation.

23. Berth

Berth is the term used in ports and harbors for a designated location where a vessel may be anchored, usually for the purposes of loading and unloading. Berths are designated by the management of a facility (e.g., port authority, harbor master). Vessels are assigned to berths by these authorities.

24. Cargo Vessels

A cargo vessel is any sort of ship or vessel that carries cargo, goods, and materials from one port to another. Cargo ships are usually specially designed for the task, often being equipped with cranes and other mechanisms to load and unload and come in all sizes. Today, they are almost always built by welded steel, and with some exceptions generally have a life expectancy of 25 to 30

25. Cartographic Cell

Cartographic cell is a cell specialized for the study and practice of making maps. Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively.

26. Channel Markers/ Navigational Aids

A navigational aid is any sort of marker which aids the traveler in navigation. Common types of such aids include lighthouses, buoys, fog signals, and day beacons.

Channel Markers/ Navigational Aids Glossary

27. Container Crane

A container crane is a type of large dockside gantry crane found at container terminals for loading and unloading containers from ships.


28. Container terminal

A container terminal is a facility where cargo containers are transshipped between different transport vehicles, for onward transportation. The transshipment may be between container ships and land vehicles, for example trains or trucks.

Container terminal Glossary

29. Country Boats

Country boats are the low-cost convenient transport in inland waterways. They are generally made of wood.

Country Boats Glossary

30. Pontoons

Pontoons are airtight hollow structures, similar to pressure vessels, designed to provide buoyancy in water. Their principal applications are in watercraft hulls and aircraft floats, floating pier and pontoon bridge construction, and marine engineering applications such as salvage.

Pontoons Glossary

31. Tidal creek

A tidal creek is the portion of a stream that is affected by flow of ocean tides, in the case that the subject stream discharges to an ocean, sea or strait.

Tidal creek Glossary

32. GPS

The Global Positioning System (GPS) is a space-based navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites

GPS Glossary

33. DGPS

Differential Global Positioning System (DGPS) is an enhancement to Global Positioning System that provides improved location accuracy, from the 15-meter nominal GPS accuracy to about 10 cm in case of the best implementations

34. Air Draft

Air draft is the distance from the surface of the water to the highest point on a vessel.

35. Deep Draft

Deep Draft is the distance from the surface of the water to the deepest part of the hull below the surface.

36. Vessel’s Clearance

It is the distance in excess of the air draft which allows a vessel to pass safely under a bridge or obstacle such as power lines, etc.

37. Dry Dock

Dry Dock is a narrow basin or vessel that can be flooded to allow a load to be floated in, then drained to allow that load to come to rest on a dry platform. Dry docks are used for the construction, maintenance, and repair of ships, boats, and other water craft.

38. Fleet

A fleet is a collection of ships or vehicles

39. Thalweg

Thalweg is the line of lowest elevation within a valley or watercourse.

Thalweg Glossary

40. Hydraulic Hammer

Hydraulic Hammer is a type of hydraulic tool or attachment that is used in demolition jobs which involve breaking up of large blocks and slabs of concrete and in excavation and quarrying of rocks and minerals.

41. Tug

A tug or tugboat is a boat that maneuvers vessels by pushing or towing them.

42. Navigational Lock

A lock is a device used for raising and lowering boats, ships and other watercraft between stretches of water of different levels on river and canal waterways. The distinguishing feature of a lock is a fixed chamber in which the water level can be varied; whereas in a caisson lock, a boat lift, or on a canal inclined plane, it is the chamber itself (usually then called a caisson) that rises and falls. Locks are used to make a river more easily navigable, or to allow a canal to take a reasonably direct line across land that is not level.

Navigational Lock Glossary

43. Patrol Boat

A patrol boat is a relatively small naval vessel generally designed for coastal defense duties

43. Pilotage

Pilotage is the use of fixed visual reference on the ground or sea by means of sight or radar to guide oneself to a destination, sometimes with the help of a map or nautical chart

46. RIS

River Information Services (RIS) are modern traffic management systems enhancing a swift electronic data transfer between water and shore through in-advance and real-time exchange of information. The major benefits of the implementation of RIS can be summarised as increased competitiveness, optimized use of infrastructure, improved safety, reduced carbon emissions and increased energy efficiency.

47. Over Dimensional Cargo (ODC)

ODC generally consists of Bridge sections, Transformers, Heavy Machineries, Boilers, Gas Turbines, Storage tanks etc.