ROUTE 581
Carrying ROUTE 581 over LITTLE RIVER
1.7 MI W OF MENOMINEE, Menominee, Michigan
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
ROUTE 581 in Menominee, Michigan sits above 25% of rated Michigan bridges on inventory load rating (33 t), while its 1962 build year is earlier than 70% of Menominee's recorded-year cohort (96 bridges).
ROUTE 581 in Menominee, Michigan is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1962, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 4. 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 MI:000000000006826
INTERSTATE-ERA · PRESTRESS · SINGLE-SPAN · SUB-LED · ARTERIAL-ADT · STANDARD-LOAD · CAT-POOR
- INTERSTATE-ERA 1950–1979
- PRESTRESS Prestressed concrete
- SINGLE-SPAN Single span
- SUB-LED Substructure-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: ROUTE 581
The ROUTE 581 bridge in Menominee, Michigan carries ROUTE 581 over LITTLE RIVER. It was built in 1962, making it 64 years old today. The structure is built primarily of prestressed concrete and spans 1 section, stretching 17.0 meters (56 feet) end to end. Daily traffic averages 1,283 vehicles, placing it in the moderately-trafficked tier of Michigan bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 5/9, superstructure at 5/9, substructure at 4/9. 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 ROUTE 581 compares
Age against the county: built in 1962, earlier than 67 of Menominee's 96 bridges with a recorded construction year (70%), 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 Michigan bridges with a recorded inventory load rating (11,366 of 11,371 rated).
ROUTE 581 vs every rated Michigan bridge
Inventory load rating (metric tons), FHWA NBI, this state
33 Top 75% higher than 25% of 11,366 bridges
rated Michigan 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.
Menominee inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 96 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
- 1962
- Material
- Prestressed Concrete
- Number of Spans
- 1
- Structure Length
- 17.0 m (56 ft)
- Deck Width
- 9.2 m (30 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 1,283 vehicles/day
- Structure Number
- 000000000006826
Condition Analysis
- • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • At 5/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • The substructure (piers and abutments) rates poor at 4/9, with advanced deterioration recorded on the latest inspection.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
ROUTE 581 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 ROUTE 581 against other structures in Menominee and across Michigan. Michigan 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 ROUTE 581?
ROUTE 581 in Menominee, Michigan has a deck rating of 5/9, superstructure rating of 5/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.
How often is ROUTE 581 inspected?
ROUTE 581'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 1,283 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ROUTE 581 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 ROUTE 581?
ROUTE 581 has an NBI inventory load rating of 32.7 metric tons.
Who is responsible for maintaining ROUTE 581?
ROUTE 581 is owned and maintained by County Highway Agency.
How old is ROUTE 581 and does age affect safety?
ROUTE 581 was built in 1962, making it 64 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.
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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.