MO 171 S
Carrying MO 171 S over MNA RR
S 17 T 28 N R 32 W, Jasper, Missouri
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
MO 171 S in Jasper, Missouri sits above 22% of rated Missouri bridges on inventory load rating (22 t), while its 1949 build year is earlier than 80% of Jasper's recorded-year cohort (471 bridges).
MO 171 S in Jasper, Missouri is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1949, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 3. The lowest applicable rating sets the federal condition category, so this Poor 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 MO:6181
PRE-1950 · STEEL · LONG-SPAN-RUN · DECK-LED · ARTERIAL-ADT · STANDARD-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- STEEL Steel
- LONG-SPAN-RUN 4 spans
- DECK-LED Deck-led
- ARTERIAL-ADT Arterial ADT
- STANDARD-LOAD Standard load
- CAT-POOR Poor
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: MO 171 S
The MO 171 S bridge in Jasper, Missouri carries MO 171 S over MNA RR. It was built in 1949, making it 77 years old today. It was last reconstructed in 1977, extending its service life. The structure is built primarily of steel continuous and spans 4 sections, stretching 74.7 meters (245 feet) end to end. Daily traffic averages 8,448 vehicles, placing it in the moderately-trafficked tier of Missouri bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 3/9, superstructure at 5/9, substructure at 6/9. The weakest component sits in poor condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules.
How MO 171 S compares
Age against the county: built in 1949, earlier than 375 of Jasper's 471 bridges with a recorded construction year (80%), against a county median build year of 1985. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Missouri bridges with a recorded inventory load rating (24,616 of 24,618 rated).
MO 171 S vs every rated Missouri bridge
Inventory load rating (metric tons), FHWA NBI, this state
22 Top 78% higher than 22% of 24,616 bridges
rated Missouri 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.
Jasper inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 471 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
- 1949
- Last Reconstructed
- 1977
- Material
- Steel Continuous
- Number of Spans
- 4
- Structure Length
- 74.7 m (245 ft)
- Deck Width
- 9.7 m (32 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 8,448 vehicles/day
- Structure Number
- 6181
Condition Analysis
- • The deck (driving surface) rates poor at 3/9, with advanced deterioration recorded on the latest inspection.
- • The superstructure (beams and supports above the deck) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
MO 171 S is in the federal Poor condition category. That is a component-based result, not a closure order.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
- Compare MO 171 S against other structures in Jasper and across Missouri. Missouri 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 MO 171 S?
MO 171 S in Jasper, Missouri has a deck rating of 3/9, superstructure rating of 5/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is MO 171 S inspected?
MO 171 S'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 8,448 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. MO 171 S is currently shown as Poor condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for MO 171 S?
MO 171 S has an NBI inventory load rating of 21.6 metric tons.
Who is responsible for maintaining MO 171 S?
MO 171 S is owned and maintained by State Highway Agency.
How old is MO 171 S and does age affect safety?
MO 171 S was built in 1949, making it 77 years old and last reconstructed in 1977.
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.
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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.