US Bridges

FM 450th ST over Grey Creek

Poor

Cherokee County, Iowa · 093402201 · Structure no. 000000000109630

Built
1970
55 years old
Condition
Poor
inspected August 2023
Type
Slab
Concrete Continuous
Length
77 ft
3 main spans
Daily traffic
319
2022 count
Owner
County
County Highway Agency

About this bridge

FM 450th ST over Grey Creek is a concrete continuous slab carrying FM 450th ST over Grey Creek in Cherokee County, Iowa. It was built in 1970, so it is 55 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 319 vehicles a day, roughly 28% of them trucks, projected to reach 319 by 2043. The structure is 77 ft (23.5 m) long and 30 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM 450th ST
CrossesGrey Creek
Location093402201
RouteCounty Highway 0
CountyCherokee County
StateIowa
Coordinates42.86566, -95.54795
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50.9 US tons
Inventory rating29.3 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length77 ft (23.5 m)
Longest span29 ft (8.8 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic319 (2022)
Projected traffic319 by 2043
Trucks28%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.1 million (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 450th ST over Grey Creek built?

It was built in 1970, making it 55 years old in 2025.

What condition is FM 450th ST over Grey Creek in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2023.

How much traffic does FM 450th ST over Grey Creek carry?

About 319 vehicles per day (2022 count), of which roughly 28% are trucks.

How long is FM 450th ST over Grey Creek?

The structure is 77 ft (23.5 m) long with a longest span of 29 ft (8.8 m) and a deck 30 ft wide.

Who owns FM 450th ST over Grey Creek?

It is owned by the County Highway Agency.