SC 18
Carrying SC 18 over SOUTHERN RAILROAD
TOWN OF JONESVILLE, Union, South Carolina
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
SC 18 in Union, South Carolina sits above 31% of rated South Carolina bridges on inventory load rating (23 t), while its 1939 build year is earlier than 89% of Union's recorded-year cohort (131 bridges).
SC 18 in Union, South Carolina is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1939, 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 SC:000000000000986
PRE-1950 · STEEL · MULTI-SPAN · SUPER-LED · ARTERIAL-ADT · STANDARD-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- STEEL Steel
- MULTI-SPAN 3 spans
- SUPER-LED Superstructure-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: SC 18
The SC 18 bridge in Union, South Carolina carries SC 18 over SOUTHERN RAILROAD. It was built in 1939, making it 87 years old today. The structure is built primarily of steel and spans 3 sections, stretching 43.1 meters (141 feet) end to end. Daily traffic averages 1,250 vehicles, placing it in the moderately-trafficked tier of South Carolina 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 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 SC 18 compares
Age against the county: built in 1939, earlier than 116 of Union's 131 bridges with a recorded construction year (89%), against a county median build year of 1975. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across South Carolina bridges with a recorded inventory load rating (9,483 of 9,490 rated).
SC 18 vs every rated South Carolina bridge
Inventory load rating (metric tons), FHWA NBI, this state
23 Top 69% higher than 31% of 9,483 bridges
rated South Carolina 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.
Union inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 131 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
- 1939
- Material
- Steel
- Number of Spans
- 3
- Structure Length
- 43.1 m (141 ft)
- Deck Width
- 15.3 m (50 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 1,250 vehicles/day
- Structure Number
- 000000000000986
Condition Analysis
- • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • At 4/9, the superstructure (beams and supports above the deck) is in poor shape, with advanced wear on file for this vintage.
- • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
SC 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 SC 18 against other structures in Union and across South Carolina. South Carolina 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 SC 18?
SC 18 in Union, South Carolina has a deck rating of 5/9, superstructure rating of 4/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is SC 18 inspected?
SC 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 1,250 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. SC 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 SC 18?
SC 18 has an NBI inventory load rating of 23.3 metric tons.
Who is responsible for maintaining SC 18?
SC 18 is owned and maintained by State Highway Agency.
How old is SC 18 and does age affect safety?
SC 18 was built in 1939, making it 87 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.