US Bridges

Local 320th St. over Small Stream

Fair

Delaware County, Iowa · 087052501 · Structure no. 000000000139931

Built
1995
30 years old
Condition
Fair
inspected May 2023
Type
Tee Beam
Prestressed Concrete
Length
41 ft
1 main span
Daily traffic
15
2022 count
Owner
County
County Highway Agency

About this bridge

Local 320th St. over Small Stream is a prestressed concrete tee beam carrying Local 320th St. over Small Stream in Delaware County, Iowa. It was built in 1995, so it is 30 years old, younger 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 15 vehicles a day, projected to reach 15 by 2043. The structure is 41 ft (12.5 m) long and 28 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesLocal 320th St.
CrossesSmall Stream
Location087052501
RouteCounty Highway 0
CountyDelaware County
StateIowa
Coordinates42.32548, -91.38206
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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 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 alignment8: Equal to present desirable criteria
Operating rating35.4 US tons
Inventory rating27.4 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length41 ft (12.5 m)
Longest span37 ft (11.3 m)
Deck width28 ft (8.5 m)
Roadway width27 ft (8.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15 (2022)
Projected traffic15 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 Local 320th St. over Small Stream built?

It was built in 1995, making it 30 years old in 2025.

What condition is Local 320th St. over Small Stream 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 Local 320th St. over Small Stream carry?

About 15 vehicles per day (2022 count).

How long is Local 320th St. over Small Stream?

The structure is 41 ft (12.5 m) long with a longest span of 37 ft (11.3 m) and a deck 28 ft wide.

Who owns Local 320th St. over Small Stream?

It is owned by the County Highway Agency.