ND HIGHWAY 18
Carrying ND HIGHWAY 18 over MAPLE RIVER
8 NORTH OF LEONARD, Cass, North Dakota
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: ND HIGHWAY 18
The ND HIGHWAY 18 bridge in Cass, North Dakota carries ND HIGHWAY 18 over MAPLE RIVER. It was built in 1985, making it 41 years old today. It was last reconstructed in 2002, extending its service life. The structure is built primarily of prestressed concrete continuous and spans 4 sections, stretching 100.4 meters (329 feet) end to end. Daily traffic averages 700 vehicles, placing it in the lower-traffic tier of North Dakota bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 5/9, substructure at 4/9. The weakest component sits in poor condition. A component scored 4 or below, placing this bridge in the federal Poor condition category rather than declaring it unsafe or closed. Its NBI inventory load rating is 32.9 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How ND HIGHWAY 18 compares
Live comparison across North Dakota.
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 How the historical reference is calculated.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
- 1985
- Last Reconstructed
- 2002
- Material
- Prestressed Concrete Continuous
- Number of Spans
- 4
- Structure Length
- 100.4 m (329 ft)
- Deck Width
- 11.7 m (38 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 700 vehicles/day
- Structure Number
- 0018064955
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates good at 7/9, with no significant deterioration on file.
- • 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) is in poor condition (4/9), showing advanced deterioration that may require priority repair.
How to read this record
ND HIGHWAY 18 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 ND HIGHWAY 18 against other structures in Cass and across North Dakota. North Dakota 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 ND HIGHWAY 18?
ND HIGHWAY 18 in Cass, North Dakota has a deck rating of 7/9, superstructure rating of 5/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.
How often is ND HIGHWAY 18 inspected?
ND HIGHWAY 18'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 700 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ND HIGHWAY 18 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 ND HIGHWAY 18?
ND HIGHWAY 18 has an NBI inventory load rating of 32.9 metric tons.
Who is responsible for maintaining ND HIGHWAY 18?
ND HIGHWAY 18 is owned and maintained by State Highway Agency.
How old is ND HIGHWAY 18 and does age affect safety?
ND HIGHWAY 18 was built in 1985, making it 41 years old and last reconstructed in 2002.
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.