US Bridges

185th Lane over Allen Creek

Poor

Harrison County, Iowa · 080431705 · Structure no. 000000000178801

Built
1986
39 years old, rebuilt 2023
Condition
Poor
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
48 ft
2 main spans
Daily traffic
5
2016 count
Owner
County
County Highway Agency

About this bridge

185th Lane over Allen Creek is a steel stringer/multi-beam or girder carrying 185th Lane over Allen Creek in Harrison County, Iowa. It was built in 1986 and reconstructed in 2023, so it is 39 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 5 vehicles a day, projected to reach 5 by 2043. The structure is 48 ft (14.6 m) long and 21 ft wide. If it were closed, the detour would be 62.1 mi (100 km).

Location

Open in Google Maps
Carries185th Lane
CrossesAllen Creek
Location080431705
RouteCounty Highway 0
CountyHarrison County
StateIowa
Coordinates41.74015, -95.88432
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
Deck8 Very GoodNo problems noted.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating51 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckCorrugated steel
Main spans2
Design loadUnknown
Structure length48 ft (14.6 m)
Longest span31 ft (9.4 m)
Deck width21 ft (6.3 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5 (2016)
Projected traffic5 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed62.1 mi (100 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 185th Lane over Allen Creek built?

It was built in 1986, making it 39 years old in 2025. It was reconstructed in 2023.

What condition is 185th Lane over Allen 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 December 2023.

How much traffic does 185th Lane over Allen Creek carry?

About 5 vehicles per day (2016 count).

How long is 185th Lane over Allen Creek?

The structure is 48 ft (14.6 m) long with a longest span of 31 ft (9.4 m) and a deck 21 ft wide.

Who owns 185th Lane over Allen Creek?

It is owned by the County Highway Agency.