US Bridges

SB I-29 over Over UP RR

Fair

Harrison County, Iowa · 0.4 Mi. N of Jct. U.S. 30 · Structure no. 000000000028130

Built
1967
58 years old
Condition
Fair
inspected March 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
141 ft
3 main spans
Daily traffic
7,750
2022 count
Owner
State
State Highway Agency

About this bridge

SB I-29 over Over UP RR is a prestressed concrete stringer/multi-beam or girder carrying SB I-29 over Over UP RR in Harrison County, Iowa. It was built in 1967, so it is 58 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 7,750 vehicles a day, roughly 31% of them trucks, projected to reach 7,750 by 2044. The structure is 141 ft (43 m) long and 43 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesSB I-29
CrossesOver UP RR
Location0.4 Mi. N of Jct. U.S. 30
RouteInterstate 29
StateIowa
Coordinates41.55583, -95.9175
Functional classRural Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating66.8 US tons
Inventory rating38.7 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length141 ft (43 m)
Longest span52 ft (15.9 m)
Deck width43 ft (13.2 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,750 (2022)
Projected traffic7,750 by 2044
Trucks31%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was SB I-29 over Over UP RR built?

It was built in 1967, making it 58 years old in 2025.

What condition is SB I-29 over Over UP RR in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in March 2024.

How much traffic does SB I-29 over Over UP RR carry?

About 7,750 vehicles per day (2022 count), of which roughly 31% are trucks.

How long is SB I-29 over Over UP RR?

The structure is 141 ft (43 m) long with a longest span of 52 ft (15.9 m) and a deck 43 ft wide.

Who owns SB I-29 over Over UP RR?

It is owned by the State Highway Agency.