Extended Operational and Trade Vocabulary

Inland Waterways, Ferries, RoRo, and Short Sea Shipping glossary

Terminology of inland and short-sea shipping: the Act of Mannheim governing Rhine navigation under the CCNR, the Atlantic Intracoastal Waterway and Albert Canal with their CEMT class ratings, anchor barges and locks, state ferry networks such as the Alaska Marine Highway, and the RoPax operators running coastal and river vehicle-passenger services.

237 defined terms.

A

Act of Mannheim: The 1868 revised treaty (building on the 1815 Vienna Congress) that codified freedom of navigation, equal treatment of flags, and toll-free passage on the Rhine, and which still governs the river…
AIWW (Atlantic Intracoastal Waterway): The roughly 1,100 mile sheltered route from Norfolk, Virginia to Key West, Florida, used by tugs, barges, fishing vessels, and recreational craft.
Alaska Marine Highway System: State-operated US ferry network running between Bellingham, Washington and Southeast and Southwest Alaska ports.
Albert Canal: The 130 km Belgian waterway linking the Port of Antwerp with Liege on the Meuse, accommodating CEMT Class VIb traffic and a chain of large hydro-electric locks.
Anchor barge: Pontoon equipped with crane and winches that lays and shifts the eight to fourteen anchors typical of a large CSD.
ANEK Lines: Cretan ferry company founded 1967 operating Piraeus to Heraklion and Piraeus to Chania alongside Adriatic services to Italy.
Articulated Tug Barge (ATB): Tug rigidly connected to a barge.
Attica Group: Greek ferry holding owning Superfast Ferries, Blue Star Ferries, and Hellenic Seaways under the Marfin Investment portfolio.
Auxiliary push-barge: A dumb barge fitted with limited steering propellers used to assist a pusher in tight bends of the Rhine or Danube.

B

Bank effect: Tendency of a ship's stern to swing toward and bow away from a close bank in shallow water.
Bareboat ferry charter: A common arrangement on secondary ferry routes where the ferry hull is leased without crew, allowing operators to scale capacity seasonally.
Barge fleeting: The practice of assembling and parking loose Mississippi barges in mid-river or shoreside fleets prior to tow make-up.
Basel: Upstream limit of large-vessel Rhine navigation in Switzerland, terminus of the navigable Rhine corridor.
Bavaria Ferry: Generic term for Danube ferries operating across the river between Bavarian and Austrian banks, often cable-guided.
BC Ferries: British Columbia Ferry Services operator of 38 vessels and 47 terminals along coastal British Columbia.
Belomor Canal: White Sea-Baltic Canal in Russia, opened 1933, linking the White Sea with Lake Onega.
BG Freight Line: The Dutch short sea container operator (part of Peel Ports Group) running feeder services between Rotterdam, Antwerp, the UK, and Ireland.
Blue Star Ferries: Attica Group brand operating Aegean services to the Cyclades, Dodecanese, and Crete from Piraeus.
Bollard pull (towboat): The static pull of a Mississippi towboat measured in pounds or tonnes, with mainline boats typically exceeding 100 tonnes bollard pull.
Borchard Lines: The Hamburg-based short sea container operator providing weekly fixed-day services between North Europe, the East Mediterranean, and Israel.
Bornholmerfaergen: Former Danish ferry operator serving Bornholm island, since absorbed by Molslinjen which runs the route under contract.
Brahmaputra: The trans-Himalayan river designated as India's National Waterway 2 (NW-2), navigable from Dhubri to Sadiya in Assam.
Brittany Ferries: French ferry operator running the western Channel and Bay of Biscay routes.
Brussels-Charleroi Canal: The 74 km Belgian canal connecting the port of Brussels to the Sambre at Charleroi, including the Ronquieres inclined plane.
Budapest Convention (CMNI): The 2001 UNECE convention on contracts for the carriage of goods by inland waterway, in force since 2005.
Bulker barge: An open or covered hopper barge used to carry dry bulk cargo such as grain, coal, ore, or aggregates on inland waterways.

C

Caledonian MacBrayne (CalMac): Scottish state-owned operator running ro-pax and small fast craft to 50-plus West Coast and Hebridean ports under Clyde and Hebrides Ferry Services contract.
Canal du Midi: The 240 km UNESCO-listed heritage canal in southern France linking Toulouse to the Etang de Thau on the Mediterranean, opened 1681.
Canal du Nord: The French 95 km canal between the Oise at Pont-l'Eveque and the Sensee Canal, used by CEMT Class IV traffic and to be supplemented by Seine-Nord Europe.
CCNR (Central Commission for the Navigation of the Rhine): The Strasbourg-based intergovernmental body, founded by the 1815 Congress of Vienna, that regulates navigation, technical standards, and crew qualifications on the Rhine.
CEMT Class I: Peniche, 38.5 m by 5.05 m, 250 to 400 tonnes capacity.
CEMT Class II: Kempenaar, 50 to 55 m by 6.6 m, 400 to 650 tonnes.
CEMT Class III: Gustav Konig type, 67 to 80 m by 8.2 m, 650 to 1,000 tonnes.
CEMT Class IV: Johann Welker type, 80 to 85 m by 9.5 m, 1,000 to 1,500 tonnes.
CEMT Class Va: Grosses Rheinschiff, 95 to 110 m by 11.4 m, 1,500 to 3,000 tonnes.
CEMT Class Vb: Pushed convoy 172 to 185 m by 11.4 m.
CEMT Class VIa: Wide vessel or pushed convoy 95 to 110 m by 22.8 m.
CEMT Class VIb: Pushed convoy 185 to 195 m by 22.8 m.
CEMT Class VIc: Large pushed convoy 270 m by 22.8 m.
CEMT Class VII: Largest pushed convoy class, 285 m by 33 m.
Chongqing: The terminus of deep-draft Yangtze navigation, with the Three Gorges Dam lifting vessels of up to 10,000 t into the upper reach.
Cleat barge: A flat-deck barge fitted with deck cleats for securing project cargo on US inland waterways.
CMNI: See Budapest Convention.
Coastal RoRo: Short sea roll-on/roll-off services such as those of CldN between Zeebrugge and the UK and Ireland.
Cologne (Koeln): A major Rhine port at km 688, traditionally the head of the lower Rhine and a key trans-shipment hub for steel and chemicals.
Color Line: Norwegian ferry operator between Norway and Germany or Denmark.
Containerships: The Finnish short sea container operator, since 2018 a CMA CGM subsidiary, specializing in LNG-fuelled Baltic and North Sea services.
Cook Strait: New Zealand waterway between Wellington and Picton served by Interislander and Bluebridge.
Coupled convoy: See Koppelverband.

D

Danube Commission: Intergovernmental body established by the Belgrade Convention 1948, seated in Budapest.
Deck Barge: Flat-decked unmanned barge used to carry pumps, salvage gear, and recovered wreckage.
DFDS: Danish ferry and ro-ro operator across the North Sea, Channel, and Baltic.
Door-step ferry: Informal term for short cable or chain ferries spanning narrow inland reaches.
Dortmund-Ems Canal: The 269 km German canal opened 1899 connecting the Ruhr industrial area with the North Sea at Emden via Munster.
Double-ended ferry: A ferry with wheelhouses and propulsion at both ends, allowing service without turning, common on BC Ferries, Washington State, and Norwegian routes.
Draft restriction (Rhine): Seasonal minimum-water draft on the Middle Rhine, with the gauge at Kaub being the controlling reference during summer low water.
Dredged Channel: A navigation channel maintained at project depth by the US Army Corps of Engineers.
Duisburg-Ruhrort: The Rhine port at the mouth of the Ruhr, the largest inland port in Europe, operated by Duisport AG.
Dunkerque-Escaut: The northern French canal corridor linking Dunkerque to the Belgian border, upgraded to CEMT Class Va.

E

ECA (Emission Control Area): Designated sea area with stricter sulphur (0.10% m/m) and NOx limits under MARPOL Annex VI.
Eckero Line: Estonian-Finnish ro-pax brand of Eckero group running Helsinki to Tallinn with M/S Finlandia.
EML (Euro Marine Logistics): The roll-on/roll-off short sea joint venture of Wallenius Wilhelmsen and Mitsui OSK Lines for European finished-vehicle distribution.
Ems-Jade Canal: The 73 km German canal between Emden on the Ems and Wilhelmshaven on the Jade Bay.
EU Directive 2016/1629: The directive laying down technical requirements for inland waterway vessels in the European Union, replacing Directive 2006/87/EC.
Eucon: The Dublin-based short sea container operator providing services between continental Europe and the island of Ireland, owned by ICG.
Europa II Barge: Pushed barge of 76.5 m by 11.4 m, standard Rhine push-tow unit.
European Standard ES-TRIN: The CESNI technical standard for inland navigation vessels, in force since 2018 and updated biennially.

F

Fastcat ferry: A high-speed catamaran ferry such as those operated by Wightlink between Portsmouth and Ryde.
Federal Maritime Commission FMC: US regulator with interest in international demolition transactions.
Feeder vessel: Jones Act compliant US-flag vessel ferrying components from port to a foreign-flag installation vessel offshore.
Finnlines: Finnish ferry operator owned by Italy's Grimaldi Group operating Baltic ro-pax and ro-ro routes from Helsinki, Naantali, Vuosaari, and Kapellskar.
Fleeting Area: Designated river bank or basin for assembling and storing barges between tows.
Foredeck barge: A barge with a raised foredeck to deflect wash and waves on open inland reaches such as Lake Pontchartrain.

G

Ganges: The Indian river forming part of National Waterway 1 from Haldia to Varanasi, 1,620 km, managed by IWAI.
GIWW (Gulf Intracoastal Waterway): The 1,300 mile sheltered US waterway from Brownsville, Texas to Saint Marks, Florida, carrying about 100 million tons of cargo per year.
GNV (Grandi Navi Veloci): The Genoa-based Italian RoPax operator owned by MSC, running services to Sardinia, Sicily, Spain, Morocco, Albania, and Tunisia.
Great Lakes-St. Lawrence Seaway System: The 3,700 km navigable system from the head of Lake Superior at Duluth to the Gulf of Saint Lawrence.
Grimaldi Group: Naples-based shipping conglomerate owning Grimaldi Lines, Minoan Lines, Finnlines, Atlantic Container Line, and Malta Motorways of the Sea.
Gross tonnage (inland): For inland vessels, gross tonnage is not used; instead, vessels are measured by deadweight in tonnes and displacement under the European inland tonnage rules.

H

Hand-steered lock: A small heritage lock such as those on the Canal du Midi or French northern canals where gates are still cranked by hand.
Hapag-Lloyd Feeder: The intra-Mediterranean and intra-Baltic short sea feeder services of Hapag-Lloyd, since 2023 expanded after the SAAM Towage acquisition.
Hellenic Seaways: Attica Group brand operating Aegean conventional and fast craft services from Piraeus and Rafina.
Heung-A Line: The South Korean intra-Asia short sea container carrier, merged with Sinokor on the JV Heung-A Line in 2020.
High-Speed Craft (HSC) Code: 1994 HSC Code and 2000 HSC Code, mandatory under SOLAS X.
Hopper barge: Self propelled or towed dredger spoil barge.
Hovercraft (Hovertravel): The British operator running the only commercial passenger hovercraft service in the world between Southsea and Ryde across the Solent.
Hub-and-spoke feeder: A short sea pattern where deep-sea container ships call at a hub port and feeders distribute to regional ports.

I

IBC Code: International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk.
Illinois Waterway: The navigable system extending from Lake Michigan at Chicago to the Mississippi River at Grafton, Illinois.
IMDG Code: International Maritime Dangerous Goods Code, mandatory under SOLAS VII Part A.
Indo-Bangladesh Protocol Route: The set of inland waterway routes (8 routes, with 11 ports of call) agreed under the 1972 Protocol between India and Bangladesh.
Inland AIS: AIS for inland waterways under EU directives.
Inland ECDIS: Standardized electronic chart system for European inland waterways.
Inland Waterways Authority of India (IWAI): The 1986-constituted statutory body administering India's National Waterways under the Ministry of Ports, Shipping and Waterways.
Inland Waterways Trust Fund: A federal trust fund financed by a barge fuel tax that supports USACE inland navigation construction and major rehabilitation.
Integrated Tug Barge (ITB): Notched ITB combination.
Interislander: KiwiRail Cook Strait ferry brand operating between Wellington and Picton.
Irish Ferries: ICG-owned operator on the Irish Sea and France routes.
Irrawaddy: The principal river of Myanmar, navigable for about 1,400 km from the delta to Bhamo, operated by Inland Water Transport (IWT) state corporation.

J

JOWI class: A series of 135 m by 17 m self-propelled inland container vessels built from 1998, named after Johann Welker's son Jowi, the largest CEMT Class VII single-hull units.
Jumbo barge: The standard 35 ft by 195 ft US inland hopper barge of about 1,500 t capacity.
Jumbo Rhine barge: Informal term for self-propelled Rhine vessels of about 110 m, the upper end of CEMT Class Va.

K

Karlsruhe: Rhine port dredged by Bilfinger Berger and inland operators.
Kaub gauge: The hydrological gauge at Kaub on the Middle Rhine, used as the controlling indicator for low-water surcharges in the Rhine spot market.
Kempenaar: Belgian-Dutch barge type defining CEMT Class II.
KiwiRail: The New Zealand state rail and ferry company that owns Interislander on Cook Strait.
KMTC (Korea Marine Transport Co.): The Seoul-headquartered intra-Asia short sea container line operating throughout East and South-East Asia.
Koppelverband: A German term ("coupled convoy") for a self-propelled motor vessel mechanically coupled to one or more dumb barges in line ahead.

L

Lash barge: lighter aboard ship system, historic but still in spares trade.
Lashing eye (RoRo): A deck-mounted D-ring on a RoRo or RoPax deck used to secure trailers and trade-vehicles with chains and webbings under IMO CSS Code.
Lock Chamber: Enclosed basin of a lock between gates.
Lockage: A single passage of a vessel or tow through a lock.
Lockmaster: The US Army Corps of Engineers official in charge of operating a specific lock-and-dam facility.

M

MacAndrews: The historic short sea container operator (founded 1770) absorbed into CMA CGM and now branded as CMA CGM Shortsea (the MacAndrews brand was retired in 2019).
Main: The principal Rhine tributary in Germany, canalized from Mainz to Bamberg and providing access to the Main-Danube Canal.
Main-Danube Canal: Rhein-Main-Donau-Kanal, 171 km, completed 1992, connecting the Rhine basin to the Danube via the European Watershed.
Mainz: The Rhine port and confluence with the Main, at km 498, hub for Hessian and Rheinhessen container, mineral oil, and agribulk flows.
Mann Lines: The Estonian-British short sea RoRo operator running services between Cuxhaven, Harwich, Paldiski, and Turku.
Mannheim: The Rhine and Neckar confluence port, the largest German Rhine port by tonnage outside the Ruhr, and the site of the 1868 Mannheim Convention.
MARAD: US Maritime Administration, oversees Title XI loan guarantees.
Marco Polo Programme: The EU programme (2003 to 2013) that subsidized modal-shift from road to short sea and rail, replaced by the CEF transport calls and Motorways of the Sea.
Marker buoy: A floating aid to navigation marking the navigable channel on inland rivers, color-coded under the IALA system.
Mekong: Southeast Asian river navigable in sections through Vietnam, Cambodia, Laos, Thailand, and China.
Mid-channel buoy: A buoy marking the centerline of the navigable channel of an inland river.
Minoan Lines: Cretan ferry company owned by Grimaldi Group operating Piraeus to Heraklion and Adriatic services.
Mississippi River: 3,766 km navigable from the Gulf of Mexico to Minneapolis via the Upper Mississippi locks.
Mittelland Canal: The 325 km east-west German canal linking the Dortmund-Ems Canal to the Elbe near Magdeburg, the longest artificial waterway in Germany.
Moby Lines: Italian ferry company operating Tyrrhenian routes from Genoa, Livorno, Piombino, and Naples to Corsica, Sardinia, and Sicily.
Modal shift: The transfer of cargo from road to rail or waterborne short sea, the principal policy goal of EU transport white papers since 2001.
Moscow Canal: The 128 km Soviet canal opened 1937 linking the Moskva River with the Volga at Dubna, providing Moscow with deep-water access.
Motorways of the Sea (MoS): The TEN-T programme designating short sea routes integrated into the trans-European transport network and eligible for CEF co-financing.
MSC Feeder: Short sea feeder operations of Mediterranean Shipping Company, separated by trade lane and frequently operating as common-feeder service to non-MSC mainline operators.

N

Nanjing: CCCC inland dredging projects on the Yangtze.
National Waterway 1 (NW-1): The Ganges-Bhagirathi-Hooghly system from Haldia to Varanasi, 1,620 km, India's flagship inland waterway with terminals at Varanasi, Sahibganj, and Haldia.
National Waterway 2 (NW-2): The Brahmaputra from Dhubri to Sadiya, 891 km.
National Waterway 3 (NW-3): The West Coast Canal in Kerala from Kollam to Kottapuram, 205 km, including the Champakara and Udyogamandal canals.
National Waterway 4 (NW-4): The Krishna-Godavari corridor in Andhra Pradesh and Telangana, 1,078 km.
National Waterways Act 2016: The Indian Parliament Act that declared 106 additional waterways (NW-4 through NW-111) bringing the total to 111 National Waterways.
Naviera Pinillos: A historical short sea operator in Spain, mentioned in the context of Iberian feeder history.
NorthLink Ferries: Operator of Scottish mainland to Orkney and Shetland services from Aberdeen and Scrabster.

O

Ohio River: US navigable river of 981 miles with locks and dams managed by USACE.
OPDR (Oldenburg-Portugiesische Dampfschiffs-Rhederei): The historic Hamburg-based short sea container line, acquired by CMA CGM in 2014 and rebranded MacAndrews-OPDR before consolidation under CMA CGM Shortsea.
Open Hopper Barge: A hopper barge without covers, used for weather-tolerant cargo such as coal and aggregates.

P

P&O Ferries: UK ferry operator on the Dover-Calais and North Sea routes.
Panmax (river-sea): River-sea vessels are not Panmax; the term is reserved for ocean-going lock-fit ships. A separate "Volga-Don-max" exists for vessels limited by the Volga-Don Canal.
Pegel (gauge): A water-level gauge along the Rhine; key references are Kaub, Duisburg-Ruhrort, and Maxau.
Peniche: French barge type, reference vessel for CEMT Class I.
Pentland Ferries: Private Scottish operator running Gills Bay to St Margaret's Hope with the catamaran Alfred.
Polferries: Polish state operator (Polska Zegluga Baltycka) running Swinoujscie to Ystad and Nynashamn.
Pontoon: Floating platform for pipeline, anchors or stationary dredgers.
Port Mansfield: An example of a designated US shallow-draft port served by the GIWW.
Pre-arrival message: The data message required from inland navigation vessels under RIS (River Information Services) before arrival at the next lock or port.
Procap convoy: An informal term for a large pushed convoy on the lower Rhine.
Push-tow: The standard formation of a pusher boat with one or more barges rigidly coupled ahead, used on the Rhine, Danube, Volga, and US inland rivers.
Pusher tug: A purpose-built vessel with a square push bow and vertical knees designed to push barges from astern.

Q

Quad-tow: A push-tow of four barges, common configuration on the Upper Mississippi above Lock 27.
Quay-side ramp (RoRo): A shore-based hinged ramp providing the slope necessary for cars and trailers to roll on or roll off a RoRo or RoPax ferry.

R

Ramp angle: The slope of a RoRo stern, side, or bow ramp, restricted to about 11 to 14 degrees for safe trailer transit.
RCL (Regional Container Lines): The Bangkok-based intra-Asia short sea container operator with a fleet of feeder-size vessels.
Rhine-Main-Danube link: The combined waterway corridor from Rotterdam via the Rhine, Main, Main-Danube Canal, and Danube to the Black Sea at Sulina, opened end-to-end in 1992.
River Information Services (RIS): The harmonized European information services for inland navigation under EU Directive 2005/44/EC, comprising Inland AIS, Inland ECDIS, electronic ship-reporting, and notices to skippers.
River-sea vessel: A vessel certified for both inland river and limited coastal sea operation, common on the Volga-Don, Rhine, and Yangtze estuary trades.
Roads of the Rhine: Informal designation of the navigation channel of the Rhine, divided into the Upper, Middle, and Lower Rhine, plus the Waal and Lek branches in the Netherlands.
RoPax: Roll-on/roll-off passenger vessel category with early uptake of LNG and battery-hybrid propulsion.
RoRo: Roll-on roll-off vessel, relevant to berthing-scale ENC depiction of linkspan structures.

S

Saint Lambert Lock: The first lock of the Montreal-Lake Ontario section of the Saint Lawrence Seaway, lifting vessels 4.5 m to bypass the Lachine Rapids.
Saint Lawrence Seaway Management Corporation: The Canadian not-for-profit corporation managing the Canadian portion of the Saint Lawrence Seaway between Montreal and Lake Erie.
Saint-Quentin Canal: The 92 km French canal between the Escaut at Cambrai and the Oise at Chauny, opened in 1810 and including the 5.6 km Riqueval tunnel.
Sambre-Oise Canal: A French canal of CEMT Class I dimensions linking the Sambre at Landrecies to the Oise at Chauny.
Saone-Rhone: The Saone and Rhone rivers form the French navigable axis from Dijon (via Saint-Jean-de-Losne) to the Mediterranean at Fos-sur-Mer, of CEMT Class Vb.
Sava: A right-bank tributary of the Danube, navigable from Sisak (Croatia) to its mouth at Belgrade and managed by the International Sava River Basin Commission.
Scandlines: Danish-German short-sea ferry operator running Puttgarden to Rodby and Rostock to Gedser hybrid ferries.
Schubverband: German for "push convoy"; the standard formation on the Rhine of one pusher and two to six barges.
SeaCo Asia: The intra-Asia short sea feeder operator working between Far East hubs and outports.
Seine-Nord Europe: The 107 km canal under construction between Compiegne on the Oise and Aubencheul-au-Bac on the Dunkerque-Escaut, sized to CEMT Class Vb, due to open in 2030.
Self-propelled Barge: Inland cargo vessel with its own propulsion, distinct from dumb barges.
Short sea shipping: Maritime transport over short distances within a region.
Sibirskiy: A Soviet-built series of river-sea cargo ships (project 292) of about 3,400 t deadweight, common on the Volga and Russian Far East.
Sinokor: The South Korean intra-Asia short sea container line headquartered in Seoul, jointly operating Heung-A Line with Heung-A Shipping.
SITC: Standard International Trade Classification, UN statistical commodity nomenclature.
Snake-Columbia Waterway: The 465 mi inland navigation route from Lewiston, Idaho via the Snake and Columbia rivers to the Pacific at Astoria, with eight federal lock-and-dam projects.
SNAV: Italian operator running fast monohull HSCs Naples to Aeolian Islands, Croatia and Sicily, now part of MSC group.
Soo Locks: The four parallel US-operated locks at Sault Sainte Marie, Michigan, lifting Great Lakes traffic 21 ft between Lake Superior and Lake Huron.
Sormovskiy: A Soviet-built river-sea cargo class (project 1557 and 488) of about 2,700 to 3,500 t deadweight, fitted for Volga-Baltic and Black Sea operation.
Spirit of Tasmania: The Bass Strait RoPax service of TT-Line Company (Tasmania) between Geelong and Devonport.
Spud Barge: A barge fitted with spuds, used for dredging and construction.
ST-class tanker: Soviet-built river-sea oil tankers, the "ST" series typified by the Volgo-Don and STK classes.
Stena Line: Swedish ferry operator across Northern Europe.
Stena RoRo: Swedish ro-ro vessel owner and partner in the Oceanbird wind-assisted concept.
Strait Shipping: The New Zealand independent RoPax operator branded Bluebridge, running Cook Strait services in competition with Interislander.
Strintzis Lines: The historic Greek RoPax operator, absorbed into the Attica Group in 2001 and rebranded Blue Star Ferries.

T

Tallink Silja: Estonian-Finnish operator (Tallink Grupp) running Helsinki, Tallinn, Stockholm, Riga and Turku routes with ro-pax and the Star and MyStar fast ro-pax.
Tank Barge: Liquid cargo barge, US standard sizes including 297 ft by 54 ft by 12 ft of about 27,500 barrels capacity.
TEN-T: Trans-European Transport Network defining the EU port hierarchy for OPS deployment.
Tennessee-Tombigbee Waterway: 234-mile canal connecting the Tennessee River with the Tombigbee River, opened 1985.
Three Gorges Ship Lift: Vertical ship lift at Three Gorges Dam on the Yangtze with 3,000 ton lift capacity.
Three Gorges Ship Lock: The two-way, five-step lock at the Three Gorges Dam, opened 2003, lifting vessels of up to 10,000 t through 113 m in about four hours.
Tirrenia: Italian ferry company now owned by Moby Lines operating Naples to Palermo, Civitavecchia to Olbia, and Genoa to Porto Torres.
Tisza: A left-bank Danube tributary navigable from Szeged (Hungary) downstream.
Tow Size: The number and arrangement of barges in a tow, often expressed as rows by columns.
Towboat: US term for an inland vessel pushing barges.
Trans-Tasman: Australian-NZ dredging market.
Triple-island barge: An old British classification rarely used on inland waters today.
TT-Line: German-Swedish operator on Travemunde, Rostock to Trelleborg.
Twente Canal: The 65 km Dutch canal from the IJssel at Zutphen to Enschede via Hengelo, of CEMT Class Va.

U

Unifeeder: The Aarhus-headquartered short sea common-feeder and shortsea container operator, owned by DP World since 2018 and the largest of its kind in Europe.
Unity Line: The Polish RoPax operator (part of Polsteam) serving the Swinoujscie-Ystad and Swinoujscie-Trelleborg routes.
US Army Corps of Engineers (USACE): The federal agency operating, maintaining, and constructing locks, dams, and dredged channels on the US inland waterway system.
US Inland Waterways System: The 12,000 mi commercial system administered by USACE, comprising the Mississippi, its tributaries, the GIWW, and the AIWW.

V

Varanasi terminal: The upstream terminal of National Waterway 1 in India, inaugurated in November 2018 as the multimodal terminal at Varanasi.
Viking Line: Finnish ferry operator on the northern Baltic, owner of Viking Cinderella.
Volga: The longest river in Europe, 3,530 km navigable from the upper headwaters to Astrakhan on the Caspian Sea.
Volga-Baltic Waterway: Russian inland route linking the Volga to the Baltic via Lake Onega and Lake Ladoga.
Volga-Caspian Canal: The seasonal navigation channel through the Volga delta giving Caspian access to Volga river-sea vessels.
Volga-Don Canal: 101 km canal opened 1952 connecting the Volga with the Don and Sea of Azov.
Volgo-Balt class: Soviet-built river-sea cargo vessels (project 2-95A) of about 3,000 t, named for the Volga-Baltic Waterway.
Volgo-Don class: A series of large Soviet river-sea cargo ships of about 5,000 t deadweight, sized to the Volga-Don Canal locks.
Volgoneft: Soviet-built river-sea oil tankers (project 550 and 1577), with the Volgoneft 250 series of about 4,800 t deadweight.
Volzhsky: A Soviet-built river-sea cargo class (project 05074M) of about 5,000 t, in service since the 1980s.

W

Waal: The principal Dutch distributary of the Rhine, the busiest inland waterway in Europe in tonnage, running 84 km from the Pannerdens Canal to the Hollands Diep.
Washington State Ferries (WSF): The state-operated ferry network of Washington, USA, the largest US ferry operator by passenger volume, serving Puget Sound and the San Juan Islands.
Welland Canal: Canadian canal of eight locks lifting vessels 99 m between Lake Ontario and Lake Erie.
Wesel-Datteln Canal: The 60 km German canal between the Rhine at Wesel and the Dortmund-Ems Canal at Datteln, of CEMT Class Vb.
Western Rivers Pilot: A US federal endorsement under 46 CFR Part 10 for piloting on the Western Rivers (Mississippi and its tributaries) under USCG-issued pilotage rules.
Westoe Marine: A heritage British inland-water builder, mentioned only for completeness.
White Sea-Baltic Canal: See Belomor Canal.
Wightlink: UK ferry operator on the Solent serving the Isle of Wight.
Wuhan: A major Yangtze River port at the confluence with the Han River, the head of 10,000 t ocean-going access on the middle Yangtze.

X

X-Press Feeders: The Singapore-headquartered global common-feeder container operator, the largest independent feeder operator outside Europe.
Xijiang: The "West River," the principal tributary of China's Pearl River, navigable from Wuzhou to Guangzhou for 1,000 t vessels and from Nanning seasonally.
Xunjiang: A section of the Pearl River system in Guangxi, navigable for Pearl River pushed convoys.

Y

Yangtze River: Continuous CCCC maintenance dredging for inland navigation.
Yangtze River Administration of Navigational Affairs (YRANA): The Chinese MOT agency administering navigation on the Yangtze.
Yellow River (Huang He): The second-longest river in China, used only for limited local navigation owing to extreme silt loads and seasonal flow.

Z

Zeebrugge: Belgian port with major ro-ro, container, and LNG terminals.
Zonal feeder service: A short sea feeder pattern aggregating cargo from multiple shippers to and from a hub port within a defined geographic zone.
Zuiderzee Works: Although primarily flood-defense, this Dutch project created the IJsselmeer and its associated CEMT Class VI navigation routes between Amsterdam, Lemmer, and Lelystad.