23 C.F.R. § 661.5
The following definitions apply to this regulation:
Approach roadway means the portion of the highway immediately adjacent to the bridge that affects the geometrics of the bridge, including the horizontal and vertical curves and grades required to connect the existing highway alignment to the new bridge alignment using accepted engineering practices and ensuring that all safety standards are met.
Construction engineering (CE) is the supervision, inspection, and other activities required to ensure the project construction meets the project's approved acceptance specifications, including but not limited to: additional survey staking functions considered necessary for effective control of the construction operations; testing materials incorporated into construction; checking shop drawings; and measurements needed for the preparation of pay estimates.
National Bridge Inventory (NBI) means an FHWA database containing bridge information and inspection data for all structures defined as highway bridges located on all public roads, on and off Federal-aid highways, including Tribally owned and federally owned bridges, private bridges that are connected to a public road on both ends of the bridge, temporary bridges, and bridges under construction with portions open to traffic, that are subject to the National Bridge Inspection Standards.
National Tribal Transportation Facility Inventory (NTTFI) means at a minimum, transportation facilities that are eligible for assistance under the TTP as defined in 25 CFR 170.5 .
Operating rating means the maximum permissible live load to which the structure may be subjected for the load configuration used in the load rating. Allowing unlimited numbers of vehicles to use the bridge at operating level may shorten the life of the bridge.
Plans, specifications, and estimates (PS & E) means construction drawings, compilation of provisions, and construction project cost estimates for the performance of the prescribed scope of work.
Preliminary engineering (PE) means planning, survey, design, engineering, and preconstruction activities (including archaeological, environmental, and right-of-way activities) related to a specific bridge project.
Public road means any road or street under the jurisdiction of and maintained by a public authority and open to public travel.
Rehabilitation means major work required to restore the structural integrity of a bridge, as well as work necessary to correct major safety defects. FHWA Bridge Preservation Guide, Spring 2018 Edition.
Replacement means total replacement of an existing bridge with a new facility constructed in the same general traffic corridor. FHWA Bridge Preservation Guide, Spring 2018 Edition.
Tribal Transportation Facility (TTF) means a public highway, road, bridge, trail, transit system, or other approved facility that is located on or provides access to Tribal land and appears on the NTTFI.
TTF bridge means a structure located on the NTTFI, including supports, erected over a depression or an obstruction, such as water, a highway, or a railway, and having a track or passageway for carrying traffic or other moving loads, and having an opening measured along the center of the roadway of more than 20 feet between undercopings of abutments or spring lines of arches, or extreme ends of the openings for multiple boxes; it may also include multiple pipes, where the clear distance between openings is less than half of the smaller contiguous opening.
23 C.F.R. §661.5