Structure 49181 · Story County, IA

I 35 NB over South Skunk River

Carries I 35 NB over South Skunk River, 2.6 Miles S Of Jct US 30.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 8 of 9.

How ratings work
Decksets the rating8/9 · Very Good
Superstructuresets the rating8/9 · Very Good
Substructuresets the rating8/9 · Very Good
Channelnot part of overall9/9 · Excellent
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT378 FT OVERALL50 FT0ELEVATION · LENGTHS TO SCALE
Deck 8/9Superstructure 8/9Substructure 8/9

378 ft end to end, longest span 107 ft: about 5 semi-trucks nose to tail. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built20188 years old
Length377.6 ft115.1 m
Daily traffic24,150counted 2023
Last inspectedApril 2024every 24 months

Location

StateIowa
CountyStory
Location2.6 Miles S Of Jct US 30
CarriesI 35 NB
CrossesSouth Skunk River
Coordinates41.97033, -93.57016

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length377.6 ft (115.1 m)
Max Span106.6 ft (32.5 m)
Deck Width63.3 ft (19.3 m)
Deck Area2221.4 sq m
Main Spans4
Year Built2018

Traffic

Avg Daily Traffic24,150 (2023)
Truck Traffic18%
Lanes On Bridge2

Inspection & Ownership

Last InspectionApril 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number000000000049181

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges