MO 366 E
Carrying MO 366 E over GRAVOIS CR
S 8 T 44 N R 6 E, St. Louis, Missouri
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: MO 366 E
The MO 366 E bridge in St. Louis, Missouri carries MO 366 E over GRAVOIS CR. It was built in 1931, making it 95 years old today. It was last reconstructed in 1972, extending its service life. The structure is built primarily of concrete and spans 1 section, stretching 15.8 meters (52 feet) end to end. Daily traffic averages 18,756 vehicles, placing it in the heavily-trafficked tier of Missouri bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 5/9, superstructure at 4/9, substructure at 5/9. The weakest component sits in poor condition. Because at least one major component scores 4 or lower, this bridge falls in FHWA's Poor condition category. That category is not a closure order. Its NBI inventory load rating is 25.2 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How MO 366 E compares
Live comparison across Missouri.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1931
- Last Reconstructed
- 1972
- Material
- Concrete
- Number of Spans
- 1
- Structure Length
- 15.8 m (52 ft)
- Deck Width
- 26.8 m (88 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 18,756 vehicles/day
- Structure Number
- 5309
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • The superstructure (beams and supports above the deck) is in poor condition (4/9), showing advanced deterioration that may require priority repair.
- • The substructure (piers and abutments) rates fair at 5/9, minor deterioration that routine maintenance should address.
How to read this record
MO 366 E 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 366 E against other structures in St. Louis 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 366 E?
MO 366 E in St. Louis, Missouri has a deck rating of 5/9, superstructure rating of 4/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is MO 366 E inspected?
MO 366 E'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 18,756 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. MO 366 E 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 366 E?
MO 366 E has an NBI inventory load rating of 25.2 metric tons.
Who is responsible for maintaining MO 366 E?
MO 366 E is owned and maintained by State Highway Agency.
How old is MO 366 E and does age affect safety?
MO 366 E was built in 1931, making it 95 years old and last reconstructed in 1972.
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.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.