US Bridges

597th Ave over Small Stream

PoorClosed to traffic

Story County, Iowa · 082232206 · Structure no. 000000000314190

Built
1974
51 years old
Condition
Poor
inspected January 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
49 ft
2 main spans
Daily traffic
30
2022 count
Owner
County
County Highway Agency

About this bridge

597th Ave over Small Stream is a steel stringer/multi-beam or girder carrying 597th Ave over Small Stream in Story County, Iowa. It was built in 1974, so it is 51 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: closed to all traffic.

It carries about 30 vehicles a day, projected to reach 30 by 2043. The structure is 49 ft (14.9 m) long and 18 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries597th Ave
CrossesSmall Stream
Location082232206
RouteCounty Highway 0
CountyStory County
StateIowa
Coordinates41.89753, -93.50855
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 inspectionJanuary 2023
Inspection intervalevery 24 months
Operating statusClosed to all traffic
ScourFoundations stable; scour above top of footing
Structural evaluation0: Immediate repair necessary to put back in service
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating0 US tons
Inventory rating0 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans2
Design loadUnknown
Structure length49 ft (14.9 m)
Longest span31 ft (9.4 m)
Deck width18 ft (5.5 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30 (2022)
Projected traffic30 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 597th Ave over Small Stream built?

It was built in 1974, making it 51 years old in 2025.

What condition is 597th Ave over Small 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 January 2023.

How much traffic does 597th Ave over Small Stream carry?

About 30 vehicles per day (2022 count).

How long is 597th Ave over Small Stream?

The structure is 49 ft (14.9 m) long with a longest span of 31 ft (9.4 m) and a deck 18 ft wide.

Who owns 597th Ave over Small Stream?

It is owned by the County Highway Agency.