US Bridges

308th Ave. over Sugar Creek

Poor

Clinton County, Iowa · 083E40404 · Structure no. 000000000125251

Built
1985
40 years old
Condition
Poor
inspected January 2024
Type
Tee Beam
Prestressed Concrete
Length
49 ft
1 main span
Daily traffic
70
2022 count
Owner
County
County Highway Agency

About this bridge

308th Ave. over Sugar Creek is a prestressed concrete tee beam carrying 308th Ave. over Sugar Creek in Clinton County, Iowa. It was built in 1985, so it is 40 years old, younger 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 70 vehicles a day, projected to reach 70 by 2044. The structure is 49 ft (14.9 m) long and 20 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
Carries308th Ave.
CrossesSugar Creek
Location083E40404
RouteCounty Highway 0
CountyClinton County
StateIowa
Coordinates42.02943, -90.49736
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 2024
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating66.2 US tons
Inventory rating39.7 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length49 ft (14.9 m)
Longest span48 ft (14.6 m)
Deck width20 ft (6.1 m)
Roadway width19 ft (5.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic70 (2022)
Projected traffic70 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 308th Ave. over Sugar Creek built?

It was built in 1985, making it 40 years old in 2025.

What condition is 308th Ave. over Sugar 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 January 2024.

How much traffic does 308th Ave. over Sugar Creek carry?

About 70 vehicles per day (2022 count).

How long is 308th Ave. over Sugar Creek?

The structure is 49 ft (14.9 m) long with a longest span of 48 ft (14.6 m) and a deck 20 ft wide.

Who owns 308th Ave. over Sugar Creek?

It is owned by the County Highway Agency.