US Bridges

305th ST over Creek

Fair

Scott County, Iowa · 080E30907 · Structure no. 000000000303425

Built
1971
54 years old
Condition
Fair
inspected April 2023
Type
Slab
Concrete Continuous
Length
72 ft
3 main spans
Daily traffic
90
2022 count
Owner
County
County Highway Agency

About this bridge

305th ST over Creek is a concrete continuous slab carrying 305th ST over Creek in Scott County, Iowa. It was built in 1971, so it is 54 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 6 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 90 vehicles a day, projected to reach 90 by 2043. The structure is 72 ft (21.9 m) long and 25 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Carries305th ST
CrossesCreek
Location080E30907
RouteCounty Highway 0
StateIowa
Coordinates41.74958, -90.62427
Functional classRural 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating40.8 US tons
Inventory rating24.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length72 ft (21.9 m)
Longest span29 ft (8.8 m)
Deck width25 ft (7.6 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic90 (2022)
Projected traffic90 by 2043
Trucks0%
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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 305th ST over Creek built?

It was built in 1971, making it 54 years old in 2025.

What condition is 305th 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 April 2023.

How much traffic does 305th ST over Creek carry?

About 90 vehicles per day (2022 count).

How long is 305th ST over Creek?

The structure is 72 ft (21.9 m) long with a longest span of 29 ft (8.8 m) and a deck 25 ft wide.

Who owns 305th ST over Creek?

It is owned by the County Highway Agency.