IS 35 S

over CST W 20TH ST CST AVE

S 7 T 49 N R 34 W, Jackson County, Missouri

Condition

Fair

Year Built

1946

Daily Traffic

146,933

Length

295 ft

About This Bridge

IS 35 S carries traffic over CST W 20TH ST CST AVE in Jackson County, Missouri. Built in 1946, this structure is 80 years old, making it a historic structure that has served the community for generations. The bridge features steel continuous construction with a girder and floorbeam design, a combination chosen by engineers to meet the specific requirements of this crossing.

Approximately 146,933 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 18% of all crossings. This heavy commercial usage significantly impacts structural wear, as a single fully-loaded truck can cause as much deck wear as thousands of passenger vehicles. Transportation planners factor this into maintenance scheduling and budget allocation.

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 295 feet, this structure falls within the typical range requiring standard inspection procedures conducted by certified bridge inspectors.

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

5

Superstructure

Fair

7

Substructure

Good

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 1946, 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

Steel Continuous is the primary structural material, which influences maintenance requirements and expected lifespan. The girder and floorbeam 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 Built1946
Year Reconstructed2013
MaterialSteel Continuous
Design TypeGirder and Floorbeam
OwnerState Highway Agency

Dimensions

Total Length295 ft (90.0 m)
Max Span19 ft (5.8 m)
Deck Width11 ft
Deck Area31,223 sq ft

Span dimensions affect structural design choices and load distribution. The deck area of 31,223 sq ft determines surface maintenance scope.

Classification

Route TypeInterstate
Route Number35
Lanes On Bridge8
Lanes Under Bridge12

Status

Toll BridgeNo
Historical SignificanceNot eligible
Scour CriticalN
Detour Length1 mi (1 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.

146,933

Avg Daily Traffic (2023)

Vehicles per day crossing this bridge

18%

Truck Traffic

Commercial vehicle percentage

198,360

Projected Future ADT

Estimated future demand

This bridge carries approximately 146,933 vehicles per day, translating to roughly 53,630,545 crossings annually. This high volume places significant demands on the structure and necessitates frequent inspections.

Commercial trucks comprise 18% 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. This high percentage of truck traffic may accelerate deterioration of deck surfaces and structural components.

Traffic projections estimate future volumes of 198,360 vehicles daily, a 35% 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

4.4 tons

Maximum allowable load for special permits

Inventory Rating

2.6 tons

Load level for normal traffic

The operating rating of 4.4 tons represents the absolute maximum load this bridge can carry under controlled conditions with special permits. The inventory rating of 2.6 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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39.345278, -95.485833

Identification

Structure Number6657
NBI IDMO-6657
State FIPS29
County FIPS095

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.

IS 35 S over CST W 20TH ST CST AVE | Missouri