US Bridges

Local over D.D. No 20

PoorPosted for load

Calhoun County, Iowa · 087322701 · Structure no. 000000000091290

Built
1900
125 years old
Condition
Poor
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
42 ft
1 main span
Daily traffic
40
2022 count
Owner
County
County Highway Agency

About this bridge

Local over D.D. No 20 is a steel stringer/multi-beam or girder carrying Local over D.D. No 20 in Calhoun County, Iowa. It was built in 1900, so it is 125 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 40 vehicles a day, projected to reach 40 by 2043. The structure is 42 ft (12.8 m) long and 26 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesLocal
CrossesD.D. No 20
Location087322701
RouteCounty Highway 0
CountyCalhoun County
StateIowa
Coordinates42.32508, -94.55996
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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 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 geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating28.7 US tons
Inventory rating15.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length42 ft (12.8 m)
Longest span41 ft (12.5 m)
Deck width26 ft (7.9 m)
Roadway width26 ft (7.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2022)
Projected traffic40 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 D.D. No 20 built?

It was built in 1900, making it 125 years old in 2025.

What condition is Local over D.D. No 20 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 July 2023.

How much traffic does Local over D.D. No 20 carry?

About 40 vehicles per day (2022 count).

How long is Local over D.D. No 20?

The structure is 42 ft (12.8 m) long with a longest span of 41 ft (12.5 m) and a deck 26 ft wide.

Who owns Local over D.D. No 20?

It is owned by the County Highway Agency.