OLD MAMALAHOA HWY
Carrying OLD MAMALAHOA HWY over KAULA GULCH
TMK 4-1-01:15, Hawaii, Hawaii
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
OLD MAMALAHOA HWY in Hawaii, Hawaii sits above 9% of rated Hawaii bridges on inventory load rating (15 t), while its 1928 build year is earlier than 86% of Hawaii's recorded-year cohort (237 bridges).
OLD MAMALAHOA HWY in Hawaii, Hawaii is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1928, 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 HI:001410001100001
PRE-1950 · STEEL · MULTI-SPAN · SUB-LED · LOCAL-ADT · LIGHT-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- STEEL Steel
- MULTI-SPAN 3 spans
- SUB-LED Substructure-led
- LOCAL-ADT Local ADT
- LIGHT-LOAD Light 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: OLD MAMALAHOA HWY
The OLD MAMALAHOA HWY bridge in Hawaii, Hawaii carries OLD MAMALAHOA HWY over KAULA GULCH. It was built in 1928, making it 98 years old today. It was last reconstructed in 2009, extending its service life. The structure is built primarily of steel and spans 3 sections, stretching 15.9 meters (52 feet) end to end. Daily traffic averages 300 vehicles, placing it in the lower-traffic tier of Hawaii bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 7/9, 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.
How OLD MAMALAHOA HWY compares
Age against the county: built in 1928, earlier than 203 of Hawaii's 237 bridges with a recorded construction year (86%), against a county median build year of 1956. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Hawaii bridges with a recorded inventory load rating (1,187 of 1,195 rated).
OLD MAMALAHOA HWY vs every rated Hawaii bridge
Inventory load rating (metric tons), FHWA NBI, this state
15 Top 91% higher than 9% of 1,187 bridges
rated Hawaii 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.
Hawaii inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 237 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
- 1928
- Last Reconstructed
- 2009
- Material
- Steel
- Number of Spans
- 3
- Structure Length
- 15.9 m (52 ft)
- Deck Width
- 4.9 m (16 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 300 vehicles/day
- Structure Number
- 001410001100001
Condition Analysis
- • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
- • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
- • At 4/9, the substructure (piers and abutments) is in poor shape, with advanced wear on file for this vintage.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
OLD MAMALAHOA HWY 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 OLD MAMALAHOA HWY against other structures in Hawaii and across Hawaii. Hawaii 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 OLD MAMALAHOA HWY?
OLD MAMALAHOA HWY in Hawaii, Hawaii has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.
How often is OLD MAMALAHOA HWY inspected?
OLD MAMALAHOA HWY'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 300 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. OLD MAMALAHOA HWY 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 OLD MAMALAHOA HWY?
OLD MAMALAHOA HWY has an NBI inventory load rating of 15.2 metric tons.
Who is responsible for maintaining OLD MAMALAHOA HWY?
OLD MAMALAHOA HWY is owned and maintained by County Highway Agency.
How old is OLD MAMALAHOA HWY and does age affect safety?
OLD MAMALAHOA HWY was built in 1928, making it 98 years old and last reconstructed in 2009.
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.