I-75 NC

over 11TH-12TH-LEWIS IN CVNGT

SBL-.3M N-JEFFERSON ST OP, Kenton County, Kentucky

Condition

Fair

Year Built

1960

Daily Traffic

79,675

Length

68 ft

About This Bridge

I-75 NC carries traffic over 11TH-12TH-LEWIS IN CVNGT in Kenton County, Kentucky. Built in 1960, this structure is 66 years old, placing it among the older bridges still in active service. The bridge features concrete continuous construction with a tee beam design, a combination chosen by engineers to meet the specific requirements of this crossing.

Approximately 79,675 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 14% 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 68 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

5

Deck Condition

Fair

5

Superstructure

Fair

5

Substructure

Fair

Channel & Protection

N/A

5

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 5 indicates some deterioration that warrants monitoring but doesn't affect structural integrity.

For a structure built in 1960, this condition level is expected given the bridge's age and usage patterns. High traffic volumes on a bridge in fair or poor condition typically elevate its priority for rehabilitation or replacement in state transportation planning.

Bridge Details

Concrete Continuous is the primary structural material, which influences maintenance requirements and expected lifespan. The tee beam 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 Built1960
MaterialConcrete Continuous
Design TypeTee Beam
OwnerState Highway Agency

Dimensions

Total Length68 ft (20.9 m)
Max Span8 ft (2.4 m)
Deck Width9 ft
Deck Area5,650 sq ft

Span dimensions affect structural design choices and load distribution. The deck area of 5,650 sq ft determines surface maintenance scope.

Classification

Route TypeInterstate
Route Number75
Lanes On Bridge4
Lanes Under Bridge6

Status

Toll BridgeNo
Historical SignificancePossibly eligible
Scour CriticalN
Detour Length

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.

79,675

Avg Daily Traffic (2017)

Vehicles per day crossing this bridge

14%

Truck Traffic

Commercial vehicle percentage

87,643

Projected Future ADT

Estimated future demand

This bridge carries approximately 79,675 vehicles per day, translating to roughly 29,081,375 crossings annually. This high volume places significant demands on the structure and necessitates frequent inspections.

Commercial trucks comprise 14% 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 87,643 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

7.1 tons

Maximum allowable load for special permits

Inventory Rating

4.2 tons

Load level for normal traffic

The operating rating of 7.1 tons represents the absolute maximum load this bridge can carry under controlled conditions with special permits. The inventory rating of 4.2 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

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40.066667, -84.850000

Identification

Structure Number059B00044L
NBI IDKY-059B00044L
State FIPS21
County FIPS117

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.

I-75 NC over 11TH-12TH-LEWIS IN CVNGT | Kentucky