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Dictionary
Back Chute:
An old channel no longer used that may be located behind an island adjacent to the present navigable channel. It is sometimes used during high water stages to navigate without having to buck the strong currents in the main channel.
(TNDOT1)
Backing Rudders:
A rudder installed forward of the screw, used for maneuvering when the propellers are turning a stem regardless of the direction of actual movement of the towboat. Also called "backing rudders."
(TNDOT1)
Backwater:
1) Water backed up by a tributary stream; 2) An area of calm water unaffected by the current of a stream.
(DOI4) (TNDOT1)
Backwater Curve:
The term applied to the profile of the water surface above a dam or other obstruction in a channel. This may also be stated as the effect on the natural water surface profile of either of two confluent streams upstream from their confluence due to flow conditions in the other stream.
(TNDOT1)
Backyard Boatbuilder:
Person that builds a boat for his own use and not for the purposes of sale. A backyard boatbuilder may subcontract all work.
(USCG1)
Balance of Trade:
The difference between a country's total imports and exports; if the exports exceed the imports, a "favorable" balance of trade exists.
(TNDOT1)
Balanced Transportation:
In its broadest interpretation, intermodalism refers to a holistic view of transportation in which individual modes work together or within their own niches to provide the user with the best choices of service, and in which the consequences on all modes of policies for a single mode are considered. This view has been called balanced, integrated, or comprehensive transportation in the past.
(BTS2)
Ballast:
Material place on a track bed to hold the track in line and elevation and to distribute its load. Suitable material consists of hard particles (e.g., crushed rock, slag, gravel) that are stable, easily tamped, permeable, and resistant to plant growth.
(TRB1)
Bar:
A submerged or emerged mound, ridge, or succession of ridges of sand or other material extending across the bottom and which may obstruct navigation.
(DOI4)
Barge:
Shallow, nonself-propelled vessels used to carry bulk commodities on the rivers and the Great Lakes.
(DOE6)
Barge Carriers:
Ships designed to carry barges. Some are fitted to act as full container-ships and can carry a varying number of barges and containers at the same time.
(MARAD2)
Base Period (Off-Peak Period):
In transit, the time of day during which vehicle requirements and schedules are not influenced by peak-period passenger volume demands (e.g., between morning and afternoon peak periods). At this time, transit riding is fairly constant and usually low to moderate in volume when compared with peak-period travel.
(TRB1)
Basic Grant:
The funds available to a State for carrying out an approved State Enforcement Plan (SEP), which include, but are not limited to: 1) Recruiting and training of personnel, payment of salaries and fringe benefits, the acquisition and maintenance of equipment except those at fixed weigh scales for the purposes of weight enforcement, and reasonable overhead costs needed to operate the program; 2) Commencement and conduct of expanded systems of enforcement; 3) Establishment of an effective out-of-service and compliance enforcement system, and 4) Retraining and replacing staff and equipment.
(49CFR350)
Basic Utility Stage I Airport:
This type of airport serves 75 percent of the single-engine and small twin-engine airplanes used for personal and business purposes. Precision approach operations are not usually anticipated. This airport is designed for small airplanes in Airport Reference Code B-I.
(FAA12)
Basic Utility Stage II Airport:
This type of airport serves all the airplanes of stage I plus some small business and air taxi-type twin-engine airplanes. Precision approach operations are not usually anticipated. This airport is also designed for small airplanes in Aircraft Reference Code B-I.
(FAA12)
Batture:
The land on either side of a river between the low water stage of the river and the top of a levee.
(TNDOT1)
Bay/Inlet:
A water area that is an opening of the sea/ocean into the land, or of an estuary, lake, or river into its shore.
(DOI3)
Beacon:
A fixed signal, mark, or light and associated facilities erected for the guidance of mariners or airplane pilots.
(DOI4)
Bear Trap:
A section of movable dam with concrete piers in either side (generally about 100 feet wide) and provided with a gate which may be raised or lowered by compressed air. The bear trap serves as a type of safety valve. When the pool level maintained at the dam becomes too high, the bear trap is lowered to permit the excess water to run out. This pool control feature of movable wicket-type dams is found on the Ohio and Illinois rivers. The Bear trap will always be located on the opposite side of the river from the lock and is very dangerous to approach when open.
(TNDOT1)
Bearing:
The horizontal direction to or from any point, usually measured clockwise from true north, magnetic north, or some other reference point, through 360 degrees.
(FAA8)
Bed-Load Movement:
Solids which are transported along the riverbed as a semi suspended sediment.
(TNDOT1)
Beginning Milepost:
The continuous milepost notation to the nearest 0.01 mile that marks the beginning of any road or trail segment.
(DOI2)
Below Minimums:
Weather conditions below the minimums prescribed by regulation for the particular action involved; (e.g., landing minimums, takeoff minimums).
(FAA4)
Berth:
1) A specific segment of wharfage where a ship ties up alongside at a pier, quay, wharf, or other structure that provides a breasting surface for the vessel. Typically, this structure is a stationary extension of an improved shore and intended to facilitate the transfer of cargo or passengers.
(MARAD1)
Beverage Semitrailer:
A van-type, drop-frame semitrailer designed and used specifically for the transport and delivery of bottled or canned beverages which has side-only access for loading and unloading this commodity.
(23CFR658)
BIA Area Certification Acceptance Plan:
A plan prepared by a specific area office which delineates how it will meet certification acceptance requirements under 23 U.S.C., Section 117(a). {This section of law was deleted in the Transportation Equity Act for the 21st Century. CA is being replaced by Stewardship Agreements.}
(FHWA21)
BIA Atlas Map:
A series of maps which depict the IRR/BIA road system by reservation and jurisdictions.
(FHWA21)
BIA Classification of Roads:
An identification of specific roads or trails that take into account current and future traffic generators, and relationships to connecting or adjacent BIA, State, county, Federal, and/or local roads.
(FHWA21)
BIA Roads System:
Those existing and proposed roads for which the BIA has or plans to obtain legal right(s)-of-way. This includes only roads for which the BIA has the primary responsibility to construct, improve, and maintain. Any additions or deletions to this system must be supported by resolution from the ITG.
(FHWA21)
BIA/FHWA Memorandum of Agreement:
An agreement between the BIA and the FHWA which contains mutually agreeable roles and responsibilities for the administration of the IRR and Highway Bridge Replacement and Rehabilitation programs.
(FHWA21)
Bicycle:
A vehicle having two tandem wheels, propelled solely by human power, upon which any person or persons may ride.
(43CFR652)
Bicycle Lane (Bike Lane):
A portion of a roadway which has been designated by striping, signing and pavement markings for the preferential or exclusive use of bicyclists.
(23CFR652)
Bicycle Path (Bike Path):
A bikeway physically separated from motorized vehicular traffic by an open space or barrier and either within the highway right-of-way or within an independent right-of-way.
(23CFR652)
Bicycle Route (Bike Route):
A segment of a system of bikeways designated by the jurisdiction having authority with appropriate directional and information markers, with or without a specific bicycle route number.
(23CFR652)
Bight of a Bend:
Deepest portion of a bend (not in depth of water); sharpest part of a curve.
(TNDOT1)
Bike Lane:
A portion of a roadway which has been designated by striping, signing and pavement markings for the preferential or exclusive use of bicyclists.
(23CFR652)
Bike Path:
A bikeway physically separated from motorized vehicular traffic by an open space or barrier and either within the highway right-of-way or within an independent right-of-way.
(23CFR652)
Bike Route:
A segment of a system of bikeways designated by the jurisdiction having authority with appropriate directional and information markers, with or without a specific bicycle route number.
(23CFR652)
Bikeway:
Any road, path, or way which in some manner is specifically designated as being open to bicycle travel, regardless of whether such facilities are designated for the exclusive use of bicycles or are to be shared with other transportation modes.
(23CFR652)
Bilateral Trade Agreement:
Commerce between two countries based on a reciprocal trade agreement which specifies the quantity of goods to be traded, the time limit of the agreement and that the balances due be remitted directly between the countries.
(TNDOT1)
Bill of Lading:
A document that establishes the terms of a contract between a shipper and a transportation company. It serves as a document of title, a contract of carriage and a receipt for goods.
(MARAD2)
Billing:
A transaction conducted by a carrier involving the determination of the proper rate and total charges for a shipment and the issuance of a freight bill.
(MARAD1)