Structure 121932 · Clinton County, IA

278th ST over Rock Creek

Carries 278th ST over Rock Creek, 081e13506.

Overall conditionGood

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

How ratings work
Decksets the rating9/9 · Excellent
Superstructuresets the rating9/9 · Excellent
Substructuresets the rating9/9 · Excellent
Channelnot part of overall9/9 · Excellent
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
CAR · 15 FT80 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 9/9Superstructure 9/9Substructure 9/9

80 ft end to end. Lengths and the car 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.

Built201511 years old
Length80.1 ft24.4 m
Daily traffic26counted 2022
Last inspectedDecember 2023every 48 months

Location

StateIowa
CountyClinton
Location081e13506
Carries278th ST
CrossesRock Creek
Coordinates41.77903, -90.81170

Physical Characteristics

MaterialSteel
DesignStringer/Multi-beam
Total Length80.1 ft (24.4 m)
Max Span38.1 ft (11.6 m)
Deck Width30.8 ft (9.4 m)
Deck Area229.4 sq m
Main Spans1
Year Built2015

Traffic

Avg Daily Traffic26 (2022)
Lanes On Bridge2

Inspection & Ownership

Last InspectionDecember 2023
Inspection FrequencyEvery 48 months
OwnerCounty Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number000000000121932

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