ALLGHNY SPG RD/637
Carrying ALLGHNY SPG RD/637 over S FORK ROANOKE RIVER
01.0 Rte 790;00.01 Rt 687, Montgomery, Virginia
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
ALLGHNY SPG RD/637 in Montgomery, Virginia sits above 83% of rated Virginia bridges on inventory load rating (64 t), while its 1975 build year is earlier than 52% of Montgomery's recorded-year cohort (196 bridges).
ALLGHNY SPG RD/637 in Montgomery, Virginia is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1975, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 5. The lowest applicable rating sets the federal condition category, so this Fair result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure VA:000000000012250
INTERSTATE-ERA · STEEL · MULTI-SPAN · SUB-LED · LOCAL-ADT · HEAVY-LOAD · CAT-FAIR
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- MULTI-SPAN 3 spans
- SUB-LED Substructure-led
- LOCAL-ADT Local ADT
- HEAVY-LOAD Heavy load
- CAT-FAIR Fair
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: ALLGHNY SPG RD/637
The ALLGHNY SPG RD/637 bridge in Montgomery, Virginia carries ALLGHNY SPG RD/637 over S FORK ROANOKE RIVER. It was built in 1975, making it 51 years old today. The structure is built primarily of steel and spans 3 sections, stretching 32.6 meters (107 feet) end to end. Daily traffic averages 560 vehicles, placing it in the lower-traffic tier of Virginia bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 6/9, substructure at 5/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds.
How ALLGHNY SPG RD/637 compares
Age against the county: built in 1975, earlier than 102 of Montgomery's 196 bridges with a recorded construction year (52%), against a county median build year of 1978. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Virginia bridges with a recorded inventory load rating (14,112 of 14,120 rated).
ALLGHNY SPG RD/637 vs every rated Virginia bridge
Inventory load rating (metric tons), FHWA NBI, this state
64 Top 17% higher than 83% of 14,112 bridges
rated Virginia bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
Montgomery inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 196 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1975
- Material
- Steel
- Number of Spans
- 3
- Structure Length
- 32.6 m (107 ft)
- Deck Width
- 11.0 m (36 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 560 vehicles/day
- Structure Number
- 000000000012250
Condition Analysis
- • The deck (driving surface) is in good condition (7/9), showing no significant deterioration.
- • The superstructure (beams and supports above the deck) rates fair at 6/9, minor deterioration that routine maintenance should address.
- • The substructure (piers and abutments) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether ALLGHNY SPG RD/637 is safe to cross today. Here is how to use it.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Learn how the 0–9 condition scale and Good/Fair/Poor categories are defined. How condition ratings work
- Compare ALLGHNY SPG RD/637 against other structures in Montgomery and across Virginia. Virginia bridges
- Noticed visible damage or a safety concern? Report it to the agency that owns the bridge, or call 911 in an emergency. How to report a bridge
Condition codes come straight from the FHWA National Bridge Inventory and are not a real-time safety judgment. Only the owning agency, a state DOT, county, or other owner, can post, restrict, or close a bridge.
Frequently Asked Questions
What do the condition ratings mean for ALLGHNY SPG RD/637?
ALLGHNY SPG RD/637 in Montgomery, Virginia has a deck rating of 7/9, superstructure rating of 6/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is ALLGHNY SPG RD/637 inspected?
ALLGHNY SPG RD/637's responsible agency sets its routine interval under FHWA's risk-based inspection rules; this page does not expose the scheduled interval. It carries about 560 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ALLGHNY SPG RD/637 is currently shown as Fair condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for ALLGHNY SPG RD/637?
ALLGHNY SPG RD/637 has an NBI inventory load rating of 63.5 metric tons.
Who is responsible for maintaining ALLGHNY SPG RD/637?
ALLGHNY SPG RD/637 is owned and maintained by State Highway Agency.
How old is ALLGHNY SPG RD/637 and does age affect safety?
ALLGHNY SPG RD/637 was built in 1975, making it 51 years old.
Disclaimer: Bridge condition data is from the FHWA NBI and reflects the last reported inspection. A Poor condition rating is not a live declaration that a bridge is closed or unsafe for travel. For current closure, posting, or safety information, contact the responsible transportation agency.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.