Questions and Answers on the Specification for the National Bridge Inventory
Except for any cited statutes or regulations, the contents of these Q&As do not have the force and effect of law and are not meant to bind the public in any way. These Q&As are intended only to provide information regarding existing requirements under the law or agency policies.
Topic: SNBI Section Border Bridges (BB)
QBB-1 Do border bridges require a data submittal from each border State?
ABB-1 Yes, neighboring States are each required to submit border bridge data. The National Performance Management Measures regulation section 23 CFR 490.411 requires the inclusion of border bridges in each State’s minimum condition level computation. Additionally, 23 CFR 490.106(d) requires the inclusion of border bridges in each States and MPO’s establishment of performance targets. The SNBI provides some relief by requiring the Designated Lead State to submit a full bridge record and the Neighboring State (non-lead) may submit an abbreviated record. Item B.L.10 Border Bridge Designated Lead State is reported by both States.
QBB-2 Which items does a Neighboring State report for a border bridge?
ABB-2 SNBI page 21 discusses border bridges and identifies the items reported by a Neighboring State (non-lead). Additional data items that are reported by the Neighboring State will not be processed.
QBB-3 Will data submitted by a Designated Lead State and Neighboring State be merged by FHWA and what differences will exist between the State bridge inventories in the NBI?
ABB-3 Yes. When FHWA incorporates the Designated Lead State submitted data into the Neighboring State bridge inventory, the data items in the abbreviated dataset, identified on page 21 of the SNBI and submitted by the Neighboring State, are retained. The differences between Designated Lead State and Neighboring State bridge records will be observable in the accepted NBI data made available for download or viewing.
QBB-4 Does a border bridge Designated Lead State report all Features datasets associated with a bridge including features located within the border of a Neighboring State?
ABB-4 Yes. Referencing SNBI page 21, all Item B.F.01 feature types and their associated datasets, regardless of location on, above, or below a bridge, and on either side of a border, are reported by the Designated Lead State. This includes all associated Features datasets for Highways, Routes, Railroads, and Navigable Waterways (reference SNBI Section 4 Features).
QBB-5 Does a border bridge Neighboring State submit all Features datasets associated with a bridge, including features located within the border of a Designated Lead State?
ABB-5 No. Referencing SNBI page 21, for Item B.F.01 Feature Type, a Neighboring State submits only highway features carried on or passing above the bridge. The associated Features datasets for Highways and Routes are reported. The Neighboring State does not report non-highway features. Referring to Item B.F.01 Feature Type, non-highway features include railroads, pathways, waterways, relief for waterways, urban features, dry terrain or side slope, and other, all of which are not reported by a Neighboring State.
QBB-6 How will FHWA merge the Features datasets submitted by a Designated Lead State and Neighboring State?
ABB-6 When FHWA incorporates the Designated Lead State Features datasets into the Neighboring State bridge inventory, we will not incorporate the highway features that are also reported by the Neighboring State, i.e., the highway features carried on or passing above the bridge and the associated datasets including the Routes datasets. Referring to SNBI Figure 1 – SNBI Data Relationships on page 5: because the Item B.F.01 Feature Type reported value serves as a unique identifier for a Features dataset, the B.F.01 reported values for highway features on and above the bridge must be consistent between the Designated Lead State and Neighboring State. Otherwise, the Neighboring State data will be applied to a different feature than the corresponding Designated Lead State data, creating inaccuracies in the Neighboring State’s dataset. This is the reason for the SNBI page 21 narrative that says, "It is essential that Item B.F.01 (Feature Type) values be assigned to the same features by both States so that the Designated Lead State’s submitted feature data are assigned to the correct feature records in the Neighboring State’s inventory."