US Bridges

257th ST over Creek

Fair

Scott County, Iowa · 079E50507 · Structure no. 000000000302900

Built
1956
69 years old, rebuilt 1990
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
152 ft
3 main spans
Daily traffic
940
2022 count
Owner
County
County Highway Agency

About this bridge

257th ST over Creek is a steel continuous stringer/multi-beam or girder carrying 257th ST over Creek in Scott County, Iowa. It was built in 1956 and reconstructed in 1990, so it is 69 years old, older than the Iowa average of 45.5 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.

It carries about 940 vehicles a day, roughly 10% of them trucks, projected to reach 940 by 2043. The structure is 152 ft (46.3 m) long and 32 ft wide. If it were closed, the detour would be 13 mi (21 km).

Location

Open in Google Maps
Carries257th ST
CrossesCreek
Location079E50507
RouteCounty Highway 0
CountyScott County
StateIowa
Coordinates41.68211, -90.39706
Functional classRural Minor Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating56.4 US tons
Inventory rating33.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length152 ft (46.3 m)
Longest span59 ft (18 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic940 (2022)
Projected traffic940 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed13 mi (21 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was 257th ST over Creek built?

It was built in 1956, making it 69 years old in 2025. It was reconstructed in 1990.

What condition is 257th ST over Creek 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 May 2023.

How much traffic does 257th ST over Creek carry?

About 940 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is 257th ST over Creek?

The structure is 152 ft (46.3 m) long with a longest span of 59 ft (18 m) and a deck 32 ft wide.

Who owns 257th ST over Creek?

It is owned by the County Highway Agency.