BIA ROUTE 421
Carrying BIA ROUTE 421 over E BR PASSADUMKEAG RIVER
7.89 KM SE LEE ME, Penobscot, Maine
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
BIA ROUTE 421 in Penobscot, Maine sits above 27% of rated Maine bridges on inventory load rating (31 t), while its 2007 build year is earlier than 15% of Penobscot's recorded-year cohort (301 bridges).
BIA ROUTE 421 in Penobscot, Maine is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 2007, 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 ME:0000S50018B0061
POST-2000 · STEEL · SINGLE-SPAN · DECK-LED · TRACE-ADT · STANDARD-LOAD · CAT-POOR
- POST-2000 2000+
- STEEL Steel
- SINGLE-SPAN Single span
- DECK-LED Deck-led
- TRACE-ADT Trace 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: BIA ROUTE 421
The BIA ROUTE 421 bridge in Penobscot, Maine carries BIA ROUTE 421 over E BR PASSADUMKEAG RIVER. It was built in 2007, making it 19 years old today. The structure is built primarily of steel and spans 1 section, stretching 12.2 meters (40 feet) end to end. Daily traffic averages 20 vehicles, placing it in the lower-traffic tier of Maine bridges. It is owned and maintained by Bureau of Indian Affairs.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 5/9, substructure at 7/9. 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 BIA ROUTE 421 compares
Age against the county: built in 2007, earlier than 46 of Penobscot's 301 bridges with a recorded construction year (15%), against a county median build year of 1966. This is one of the newer structures in its county.
Live comparison across Maine bridges with a recorded inventory load rating (2,518 rated).
BIA ROUTE 421 vs every rated Maine bridge
Inventory load rating (metric tons), FHWA NBI, this state
31 Top 73% higher than 27% of 2,518 bridges
rated Maine 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.
Penobscot inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 301 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
- 2007
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 12.2 m (40 ft)
- Deck Width
- 4.9 m (16 ft)
- Owner
- Bureau of Indian Affairs
- Avg Daily Traffic
- 20 vehicles/day
- Structure Number
- 0000S50018B0061
Condition Analysis
- • The deck (driving surface) rates poor at 4/9, with advanced deterioration recorded on the latest inspection.
- • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
- • 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
BIA ROUTE 421 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 BIA ROUTE 421 against other structures in Penobscot and across Maine. Maine 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 BIA ROUTE 421?
BIA ROUTE 421 in Penobscot, Maine has a deck rating of 4/9, superstructure rating of 5/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is BIA ROUTE 421 inspected?
BIA ROUTE 421'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 20 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. BIA ROUTE 421 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 BIA ROUTE 421?
BIA ROUTE 421 has an NBI inventory load rating of 31.3 metric tons.
Who is responsible for maintaining BIA ROUTE 421?
BIA ROUTE 421 is owned and maintained by Bureau of Indian Affairs.
How old is BIA ROUTE 421 and does age affect safety?
BIA ROUTE 421 was built in 2007, making it 19 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.