US Bridges

305th ST over Unnamed Waterway

Good

Butler County, Iowa · 090161303 · Structure no. 000000000366075

Built
2014
11 years old
Condition
Good
inspected March 2021
Type
Tee Beam
Prestressed Concrete
Length
36 ft
1 main span
Daily traffic
35
2022 count
Owner
County
County Highway Agency

About this bridge

305th ST over Unnamed Waterway is a prestressed concrete tee beam carrying 305th ST over Unnamed Waterway in Butler County, Iowa. It was built in 2014, so it is 11 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 35 vehicles a day, projected to reach 35 by 2043. The structure is 36 ft (11 m) long and 28 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries305th ST
CrossesUnnamed Waterway
Location090161303
RouteCounty Highway 0
CountyButler County
StateIowa
Coordinates42.60645, -92.67318
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating46.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHL 93
Structure length36 ft (11 m)
Longest span35 ft (10.7 m)
Deck width28 ft (8.6 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic35 (2022)
Projected traffic35 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 Unnamed Waterway built?

It was built in 2014, making it 11 years old in 2025.

What condition is 305th ST over Unnamed Waterway in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in March 2021.

How much traffic does 305th ST over Unnamed Waterway carry?

About 35 vehicles per day (2022 count).

How long is 305th ST over Unnamed Waterway?

The structure is 36 ft (11 m) long with a longest span of 35 ft (10.7 m) and a deck 28 ft wide.

Who owns 305th ST over Unnamed Waterway?

It is owned by the County Highway Agency.