US Bridges

305th ST over Stream

PoorPosted for load

Scott County, Iowa · 080E31205 · Structure no. 000000000303451

Built
1976
49 years old
Condition
Poor
inspected April 2023
Type
Slab
Concrete
Length
32 ft
1 main span
Daily traffic
143
2021 count
Owner
County
County Highway Agency

About this bridge

305th ST over Stream is a concrete slab carrying 305th ST over Stream in Scott County, Iowa. It was built in 1976, so it is 49 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. Its operating status is: posted for load restriction.

It carries about 143 vehicles a day, projected to reach 143 by 2043. The structure is 32 ft (9.8 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries305th ST
CrossesStream
Location080E31205
RouteCounty Highway 0
CountyScott County
StateIowa
Coordinates41.74953, -90.55299
Functional classRural Local

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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating32.3 US tons
Inventory rating16.2 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length32 ft (9.8 m)
Longest span30 ft (9.1 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic143 (2021)
Projected traffic143 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 305th ST over Stream built?

It was built in 1976, making it 49 years old in 2025.

What condition is 305th ST over Stream 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 April 2023.

How much traffic does 305th ST over Stream carry?

About 143 vehicles per day (2021 count).

How long is 305th ST over Stream?

The structure is 32 ft (9.8 m) long with a longest span of 30 ft (9.1 m) and a deck 26 ft wide.

Who owns 305th ST over Stream?

It is owned by the County Highway Agency.