HWY 40 CAPITOL HWY

over B-139 X BARBUR BLVD

CAPITOL HWY AT BARBUR BVD, Multnomah County, Oregon

Condition

Fair

Year Built

1959

Daily Traffic

11,908

Length

55 ft

About This Bridge

HWY 40 CAPITOL HWY carries traffic over B-139 X BARBUR BLVD in Multnomah County, Oregon. Built in 1959, this structure is 67 years old, placing it among the older bridges still in active service. The bridge features steel construction with a stringer/multi-beam or girder design, a combination chosen by engineers to meet the specific requirements of this crossing.

Approximately 11,908 vehicles cross this bridge daily, representing moderate traffic volumes typical of important regional connectors. This level of usage requires regular monitoring to ensure continued safe operation. Commercial trucks account for 1% of all crossings. This proportion of commercial traffic is typical for this roadway classification and is factored into the bridge's design load ratings.

The bridge is currently rated in fair condition based on federal inspection criteria established by the Federal Highway Administration. The structure meets current safety standards for its designated use and load capacity. With a total length of 55 feet, this is a shorter span typical of local road crossings, often carrying traffic over small streams, drainage channels, or other roadways.

Steel bridges provide high strength-to-weight ratios, making them suitable for longer spans. However, they require ongoing protection against corrosion through painting or weathering steel designs. Inspectors pay close attention to connection points, fatigue cracking, and coating condition.

Federal law requires that all highway bridges be inspected at least every 24 months by qualified inspectors following the National Bridge Inspection Standards (NBIS). Some bridges with known issues or unusual characteristics may be inspected more frequently. Inspection data is reported to the National Bridge Inventory, a database maintained by the Federal Highway Administration that tracks the condition of all public highway bridges in the United States. This bridge data is sourced from that federal database and reflects the most recent available inspection results.

Condition Ratings

6

Deck Condition

Satisfactory

6

Superstructure

Satisfactory

6

Substructure

Satisfactory

Channel & Protection

N/A

6

Lowest Rating

Determines condition category

NBI condition ratings range from 0 (failed) to 9 (excellent). Ratings of 4 or below are considered poor. The overall condition category is determined by the lowest individual component rating.

The fair condition rating of 6 indicates satisfactory condition with minor section loss or deterioration.

For a structure built in 1959, this condition level is expected given the bridge's age and usage patterns.

Bridge Details

Steel is the primary structural material, which influences maintenance requirements and expected lifespan. The stringer/multi-beam or girder design was selected based on span requirements, load capacity needs, and site conditions at the time of construction. Maintenance responsibility falls to City/Municipal.

Construction

Year Built1959
MaterialSteel
Design TypeStringer/Multi-beam or Girder
OwnerCity/Municipal

Dimensions

Total Length55 ft (16.9 m)
Max Span11 ft (3.2 m)
Deck Width3 ft
Deck Area1,334 sq ft

Span dimensions affect structural design choices and load distribution. The deck area of 1,334 sq ft determines surface maintenance scope.

Classification

Route TypeCity Street
Route Number1
Lanes On Bridge1
Lanes Under Bridge4

Status

Toll BridgeNo
Historical SignificanceNot eligible
Scour CriticalN
Detour Length2 mi (3 km)

Traffic Data

Traffic volume data helps engineers assess bridge wear patterns and plan maintenance schedules. Average Daily Traffic (ADT) counts are updated periodically and represent typical weekday usage.

11,908

Avg Daily Traffic (2020)

Vehicles per day crossing this bridge

1%

Truck Traffic

Commercial vehicle percentage

13,133

Projected Future ADT

Estimated future demand

This bridge carries approximately 11,908 vehicles per day, translating to roughly 4,346,420 crossings annually. This moderate traffic level is typical for regional connectors.

Commercial trucks comprise 1% of traffic. Heavy vehicles cause disproportionate wear—a single fully loaded truck can have the impact of thousands of passenger cars on bridge deck surfaces.

Traffic projections estimate future volumes of 13,133 vehicles daily, a 10% increase from current levels. These projections inform capacity planning and potential upgrade requirements.

Load Ratings

Load ratings determine what weight this bridge can safely support. These values are critical for routing heavy vehicles and issuing overweight permits.

Operating Rating

3.6 tons

Maximum allowable load for special permits

Inventory Rating

2.8 tons

Load level for normal traffic

The operating rating of 3.6 tons represents the absolute maximum load this bridge can carry under controlled conditions with special permits. The inventory rating of 2.8 tons is the safe load limit for everyday traffic without restrictions. These relatively low ratings may result in posted weight limits or route restrictions for heavy vehicles.

5-Year Condition Trend

Declining

Condition has declined by 1.0 rating points since 2020

Data: 2020-2024 FHWA National Bridge Inventory

Location

Loading map...

46.841667, -124.016944

Identification

Structure Number08551 040 00672
NBI IDOR-08551 040 00672
State FIPS41
County FIPS051

Explore More

Data Source: Federal Highway Administration (FHWA) National Bridge Inventory 2024

Bridge inspection data is typically updated every 24 months. Conditions may have changed since the last inspection.

“Structurally deficient” does not mean a bridge is unsafe or likely to collapse. It indicates that one or more key structural elements are in poor or worse condition. Bridges are inspected regularly and may have load restrictions in place.

This data is for informational purposes only and should not be used for route clearance or vehicle weight decisions.

HWY 40 CAPITOL HWY over B-139 X BARBUR BLVD | Oregon