Hwy 100
Carrying Hwy 100 over Horsetail Falls
2.5 MI E MULTNOMAH FALLS, Multnomah, Oregon
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: Hwy 100
The Hwy 100 bridge in Multnomah, Oregon carries Hwy 100 over Horsetail Falls. It was built in 1914, making it 112 years old today. The structure is built primarily of concrete continuous and spans 3 sections, stretching 18.3 meters (60 feet) end to end. Daily traffic averages 781 vehicles, placing it in the lower-traffic tier of Oregon bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 6/9, superstructure at 7/9, substructure at 5/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 19.8 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How Hwy 100 compares
Live comparison across Oregon.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1914
- Material
- Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 18.3 m (60 ft)
- Deck Width
- 7.3 m (24 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 781 vehicles/day
- Structure Number
- 04543 125 02221
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
- • At 5/9, the substructure (piers and abutments) shows fair condition, with minor wear flagged for upkeep.
How to read this record
This page shows what the last federal inspection recorded, not whether Hwy 100 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 Hwy 100 against other structures in Multnomah and across Oregon. Oregon 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 Hwy 100?
Hwy 100 in Multnomah, Oregon has a deck rating of 6/9, superstructure rating of 7/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is Hwy 100 inspected?
Hwy 100'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 781 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. Hwy 100 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 Hwy 100?
Hwy 100 has an NBI inventory load rating of 19.8 metric tons.
Who is responsible for maintaining Hwy 100?
Hwy 100 is owned and maintained by State Highway Agency.
How old is Hwy 100 and does age affect safety?
Hwy 100 was built in 1914, making it 112 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.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.