Overview of Bridges and the City of Lincoln's Role
National Bridge inspection Standards
There are four letters that define the scope of bridge inspections in this country: NBIS, meaning National Bridge inspection Standards. The National Bridge Inspection Standards (NBIS) are Federal regulations establishing requirements for:
- Inspection Procedures
- Frequency of Inspections
- Qualifications of Personnel
- Inspection Reports
- Maintenance of Bridge Inventory
The National Bridge Inventory (NBI) is the aggregation of structure inventory and appraisal data collected by each state to fulfill the requirements of NBIS.
The State of Nebraska is ultimately responsible for the inspection of all public highway bridges within the State, except for those that are federally or tribally owned. The State may delegate bridge inspection policies and procedures, quality assurance and quality control, preparation and maintenance of a bridge inventory, bridge inspections, reports, load ratings and other requirements of these standards to smaller units of the State like a city or county. However, such delegation does not relieve the State transportation department or Federal Agency of any of its responsibilities. Because of the fundamental relationship established in Title 23 of the U.S. Code between the FHWA and a State, if the inspections by a city or county were not done in accordance with the NBIS, the FHWA could withhold Federal-aid highway funds from the State.
The following map and information are the structures delegated by the State of Nebraska to be inspected by the City of Lincoln. You will notice bridges in Lincoln that aren't on the map such as the pedestrian bridges on Hwy #2 east of 27th St. and the bridge on "O" St. east of 70th St. Bridges on or over State Highways such as Hwy. #2 and Hwy. #34 the Nebraska Department of Roads inspects.
Structures the City of Lincoln is required to include:
According to the Recording and Coding Guide for the Structure Inventory and Appraisal of the Nation's Bridges the minimum length for a structure carrying traffic loads is 6.1 meters (20 feet). The structure length is measured as shown on Figure P.1.1.
23 CFR Part 650.305 Definitions gives the definition of a bridge as it applies to the NBIS regulations. From the NBIS regulations, a bridge is defined as follows: a structure including supports erected over a depression or an obstruction, such as water, highway, or 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 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.