US Bridges

Thornton RD over Shady Grove CR

FairPosted for load

St. Louis County, Missouri · S 1953 T 45 N R 6 E · Structure no. 24015

Built
1965
60 years old
Condition
Fair
inspected January 2024
Type
Culvert
Steel
Length
35 ft
1 main span
Daily traffic
500
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Thornton RD over Shady Grove CR is a steel culvert carrying Thornton RD over Shady Grove CR in St. Louis County, Missouri. It was built in 1965, so it is 60 years old, older than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 500 vehicles a day, roughly 10% of them trucks, projected to reach 675 by 2043. The structure is 35 ft (10.7 m) long. If it were closed, the detour would be 0.6 mi (1 km).

Location

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CarriesThornton RD
CrossesShady Grove CR
LocationS 1953 T 45 N R 6 E
RouteCity Street 0
CountySt. Louis County
StateMissouri
Coordinates38.60437, -90.3519
Functional classUrban Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating55.6 US tons
Inventory rating24.8 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadOther
Structure length35 ft (10.7 m)
Longest span24 ft (7.3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic500 (2023)
Projected traffic675 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Thornton RD over Shady Grove CR built?

It was built in 1965, making it 60 years old in 2025.

What condition is Thornton RD over Shady Grove CR in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in January 2024.

How much traffic does Thornton RD over Shady Grove CR carry?

About 500 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Thornton RD over Shady Grove CR?

The structure is 35 ft (10.7 m) long with a longest span of 24 ft (7.3 m).

Who owns Thornton RD over Shady Grove CR?

It is owned by the City or Municipal Highway Agency.