STATE ROUTE 91

over BNSF RY AMTRAK METROLINK

08-RIV-091-R1.14, Riverside County, California

Condition

Good

Year Built

1970

Daily Traffic

264,000

Length

53 ft

About This Bridge

STATE ROUTE 91 carries traffic over BNSF RY AMTRAK METROLINK in Riverside County, California. Built in 1970, this structure is 56 years old, placing it among the older bridges still in active service. The bridge features prestressed concrete continuous construction with a box beam - multiple design, a combination chosen by engineers to meet the specific requirements of this crossing.

Approximately 264,000 vehicles cross this bridge daily, making it a high-traffic corridor critical to regional transportation. Bridges carrying this volume require enhanced inspection schedules and proactive maintenance programs. Commercial trucks account for 8% 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 good 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 53 feet, this is a shorter span typical of local road crossings, often carrying traffic over small streams, drainage channels, or other roadways.

The construction materials used in this bridge were selected based on engineering requirements, cost considerations, and local conditions at the time of construction.

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

7

Deck Condition

Good

7

Superstructure

Good

7

Substructure

Good

Channel & Protection

N/A

7

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.

With a lowest rating of 7, this bridge demonstrates good condition meeting all safety standards.

For a structure built in 1970, maintaining good condition demonstrates effective maintenance practices.

Bridge Details

Prestressed Concrete Continuous is the primary structural material, which influences maintenance requirements and expected lifespan. The box beam - multiple design was selected based on span requirements, load capacity needs, and site conditions at the time of construction. Maintenance responsibility falls to State Highway Agency.

Construction

Year Built1970
Year Reconstructed2012
MaterialPrestressed Concrete Continuous
Design TypeBox Beam - Multiple
OwnerState Highway Agency

Dimensions

Total Length53 ft (16.1 m)
Max Span16 ft (4.8 m)
Deck Width25 ft
Deck Area12,196 sq ft

Span dimensions affect structural design choices and load distribution. The deck area of 12,196 sq ft determines surface maintenance scope.

Classification

Route TypeState Highway
Route Number91
Lanes On Bridge15
Lanes Under Bridge2

Status

Toll BridgeNo
Historical SignificanceNot eligible
Scour CriticalN
Detour Length1 mi (2 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.

264,000

Avg Daily Traffic (2019)

Vehicles per day crossing this bridge

8%

Truck Traffic

Commercial vehicle percentage

304,742

Projected Future ADT

Estimated future demand

This bridge carries approximately 264,000 vehicles per day, translating to roughly 96,360,000 crossings annually. This high volume places significant demands on the structure and necessitates frequent inspections.

Commercial trucks comprise 8% 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 304,742 vehicles daily, a 15% 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

10.0 tons

Maximum allowable load for special permits

Inventory Rating

6.4 tons

Load level for normal traffic

The operating rating of 10.0 tons represents the absolute maximum load this bridge can carry under controlled conditions with special permits. The inventory rating of 6.4 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

Stable

Condition has remained relatively stable since 2020

Data: 2020-2024 FHWA National Bridge Inventory

Location

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35.136111, -118.184444

Identification

Structure Number56 0634
NBI IDCA-56 0634
State FIPS06
County FIPS065

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.

STATE ROUTE 91 over BNSF RY AMTRAK METROLINK, California — Bridge Condition | BridgeReport.org | BridgeReport.org