US Bridges

Local over Drainage

PoorPosted for load

Mahaska County, Iowa · 077171604 · Structure no. 000000000238450

Built
1950
75 years old
Condition
Poor
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
23 ft
1 main span
Daily traffic
34
2022 count
Owner
County
County Highway Agency

About this bridge

Local over Drainage is a steel stringer/multi-beam or girder carrying Local over Drainage in Mahaska County, Iowa. It was built in 1950, so it is 75 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: posted for load restriction.

It carries about 34 vehicles a day, projected to reach 34 by 2043. The structure is 23 ft (7 m) long and 21 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesLocal
CrossesDrainage
Location077171604
RouteCounty Highway 0
CountyMahaska County
StateIowa
Coordinates41.46928, -92.81801
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.
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
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 alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating20.8 US tons
Inventory rating15.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length23 ft (7 m)
Longest span21 ft (6.4 m)
Deck width21 ft (6.5 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic34 (2022)
Projected traffic34 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 statusPossibly eligible for the National Register; requires further investigation
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Local over Drainage built?

It was built in 1950, making it 75 years old in 2025.

What condition is Local over Drainage 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 Local over Drainage carry?

About 34 vehicles per day (2022 count).

How long is Local over Drainage?

The structure is 23 ft (7 m) long with a longest span of 21 ft (6.4 m) and a deck 21 ft wide.

Who owns Local over Drainage?

It is owned by the County Highway Agency.