US Bridges

150th ST over Keigley Branch

Good

Story County, Iowa · 085243501 · Structure no. 000000000316461

Built
1977
48 years old
Condition
Good
inspected November 2022
Type
Culvert
Concrete Continuous
Length
44 ft
3 main spans
Daily traffic
100
2022 count
Owner
County
County Highway Agency

About this bridge

150th ST over Keigley Branch is a concrete continuous culvert carrying 150th ST over Keigley Branch in Story County, Iowa. It was built in 1977, so it is 48 years old, older 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 100 vehicles a day, projected to reach 100 by 2043. The structure is 44 ft (13.4 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries150th ST
CrossesKeigley Branch
Location085243501
RouteCounty Highway 0
CountyStory County
StateIowa
Coordinates42.13723, -93.60652
Functional classRural Minor Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert7 GoodSome minor problems.
Last inspectionNovember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating30.1 US tons
Inventory rating18 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadHS 20
Structure length44 ft (13.4 m)
Longest span12 ft (3.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2022)
Projected traffic100 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 150th ST over Keigley Branch built?

It was built in 1977, making it 48 years old in 2025.

What condition is 150th ST over Keigley Branch 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 November 2022.

How much traffic does 150th ST over Keigley Branch carry?

About 100 vehicles per day (2022 count).

How long is 150th ST over Keigley Branch?

The structure is 44 ft (13.4 m) long with a longest span of 12 ft (3.7 m).

Who owns 150th ST over Keigley Branch?

It is owned by the County Highway Agency.