Route 12A
Carrying Route 12A over Namo River
.1mi W of RTE12 n Pale F., Unknown County, Guam
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
Route 12A in Unknown County, Guam sits above 38% of rated Guam bridges on inventory load rating (23 t), while its 1977 build year is earlier than 57% of Unknown County's recorded-year cohort (47 bridges).
Route 12A in Unknown County, Guam is rated Good in the FHWA's 2024 National Bridge Inventory. Built in 1977, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 7. The lowest applicable rating sets the federal condition category, so this Good 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 GU:66181000012G026
INTERSTATE-ERA · CONCRETE · SINGLE-SPAN · TIED-CTRL · LOCAL-ADT · STANDARD-LOAD · CAT-GOOD
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- SINGLE-SPAN Single span
- TIED-CTRL Tied control
- LOCAL-ADT Local ADT
- STANDARD-LOAD Standard load
- CAT-GOOD Good
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 12A
The Route 12A bridge in Unknown County, Guam carries Route 12A over Namo River. It was built in 1977, making it 49 years old today. The structure is built primarily of concrete and spans 1 section, stretching 15.5 meters (51 feet) end to end. Daily traffic averages 500 vehicles, placing it in the lower-traffic tier of Guam bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in good condition. None of this bridge's reported major components fall into the Poor condition range.
How Route 12A compares
Age against the county: built in 1977, earlier than 27 of Unknown County's 47 bridges with a recorded construction year (57%), against a county median build year of 1982. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Guam bridges with a recorded inventory load rating (45 of 47 rated).
Route 12A vs every rated Guam bridge
Inventory load rating (metric tons), FHWA NBI, this state
23 Top 62% higher than 38% of 45 bridges
rated Guam 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.
Unknown County inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 47 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
- 1977
- Material
- Concrete
- Number of Spans
- 1
- Structure Length
- 15.5 m (51 ft)
- Deck Width
- 10.3 m (34 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 500 vehicles/day
- Structure Number
- 66181000012G026
Condition Analysis
- • The deck (driving surface) rates good at 7/9, with no significant deterioration on file.
- • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
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 Route 12A 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 Route 12A against other structures in Unknown County and across Guam. Guam 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 12A?
Route 12A in Unknown County, Guam has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is Route 12A inspected?
Route 12A'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 500 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. Route 12A is currently shown as Good condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for Route 12A?
Route 12A has an NBI inventory load rating of 23.3 metric tons.
Who is responsible for maintaining Route 12A?
Route 12A is owned and maintained by State Highway Agency.
How old is Route 12A and does age affect safety?
Route 12A was built in 1977, making it 49 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.