TWIN ARCH ROAD
Carrying TWIN ARCH ROAD over SOUTH BR PATAPSCO RIVER
ON HOWARD CO LINE, Carroll, Maryland
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
TWIN ARCH ROAD in Carroll, Maryland sits above 72% of rated Maryland bridges on inventory load rating (58 t), while its 1987 build year is earlier than 20% of Carroll's recorded-year cohort (205 bridges).
TWIN ARCH ROAD in Carroll, Maryland is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1987, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. The lowest applicable rating sets the federal condition category, so this Fair 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 MD:200000CL0306020
LATE-CENTURY · CONCRETE · SHORT-BRIDGE · CULVERT-LED · ARTERIAL-ADT · HEAVY-LOAD · CAT-FAIR
- LATE-CENTURY 1980–1999
- CONCRETE Concrete
- SHORT-BRIDGE 16.2 m
- CULVERT-LED Culvert-led
- ARTERIAL-ADT Arterial ADT
- HEAVY-LOAD Heavy load
- CAT-FAIR Fair
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: TWIN ARCH ROAD
The TWIN ARCH ROAD bridge in Carroll, Maryland carries TWIN ARCH ROAD over SOUTH BR PATAPSCO RIVER. It was built in 1987, making it 39 years old today. The structure is built primarily of concrete, stretching 16.2 meters (53 feet) end to end. Daily traffic averages 4,137 vehicles, placing it in the moderately-trafficked tier of Maryland bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show culvert at 6/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds.
How TWIN ARCH ROAD compares
Age against the county: built in 1987, earlier than 41 of Carroll's 205 bridges with a recorded construction year (20%), against a county median build year of 1974. This is one of the newer structures in its county.
Live comparison across Maryland bridges with a recorded inventory load rating (5,479 of 5,484 rated).
TWIN ARCH ROAD vs every rated Maryland bridge
Inventory load rating (metric tons), FHWA NBI, this state
58 Top 28% higher than 72% of 5,479 bridges
rated Maryland 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.
Carroll inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 205 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
- 1987
- Material
- Concrete
- Structure Length
- 16.2 m (53 ft)
- Deck Width
- 12.2 m (40 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 4,137 vehicles/day
- Structure Number
- 200000CL0306020
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether TWIN ARCH ROAD is safe to cross today. Here is how to use it.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Learn how the 0–9 condition scale and Good/Fair/Poor categories are defined. How condition ratings work
- Compare TWIN ARCH ROAD against other structures in Carroll and across Maryland. Maryland 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 TWIN ARCH ROAD?
TWIN ARCH ROAD in Carroll, Maryland on the FHWA's 0–9 scale.
How often is TWIN ARCH ROAD inspected?
TWIN ARCH ROAD'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 4,137 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. TWIN ARCH ROAD is currently shown as Fair condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for TWIN ARCH ROAD?
TWIN ARCH ROAD has an NBI inventory load rating of 57.6 metric tons.
Who is responsible for maintaining TWIN ARCH ROAD?
TWIN ARCH ROAD is owned and maintained by County Highway Agency.
How old is TWIN ARCH ROAD and does age affect safety?
TWIN ARCH ROAD was built in 1987, making it 39 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.