Structure 1020 · Adair County, IA

Antique Co.dr over Middle River

Carries Antique Co.dr over Middle River, 77320352.

Overall conditionFair

Set by its lowest-rated component: Substructure at 6 of 9.

How ratings work
Deck7/9 · Good
Superstructure7/9 · Good
Substructuresets the rating6/9 · Satisfactory
Channelnot part of overall7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT158 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9Superstructure 7/9Substructure 6/9 · sets the rating

158 ft end to end, longest span 52 ft: about 2 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.

Built1958rebuilt 2001
Length158.1 ft48.2 m
Daily traffic969counted 2022
Last inspectedMay 2024every 24 months

Location

StateIowa
CountyAdair
Location77320352
CarriesAntique Co.dr
CrossesMiddle River
Coordinates41.50166, -94.51990

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length158.1 ft (48.2 m)
Max Span52.2 ft (15.9 m)
Deck Width33.1 ft (10.1 m)
Deck Area486.8 sq m
Main Spans3
Year Built1958 (reconstructed 2001)

Traffic

Avg Daily Traffic969 (2022)
Truck Traffic20%
Lanes On Bridge2

Inspection & Ownership

Last InspectionMay 2024
Inspection FrequencyEvery 24 months
OwnerCounty Highway Agency
Historical SignificanceBridge is possibly eligible (requires evaluation)
Scour Critical8 — Stable, low risk
Structure Number000000000001020

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.

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