Structure 289860 · Pottawattamie County, IA

400th Street over Drainage

Carries 400th Street over Drainage, 077401102.

Overall conditionFair

Set by its lowest-rated component: Deck and Substructure at 5 of 9.

How ratings work
Decksets the rating5/9 · Fair
Superstructure6/9 · Satisfactory
Substructuresets the rating5/9 · Fair
Channelnot part of overall5/9 · Fair
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
CAR · 15 FT54 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 5/9 · sets the ratingSuperstructure 6/9Substructure 5/9 · sets the rating

54 ft end to end, longest span 23 ft. 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.

Built1948rebuilt 1992
Length54.1 ft16.5 m
Daily traffic40counted 2021
Last inspectedMay 2023every 24 months

Location

StateIowa
CountyPottawattamie
Location077401102
Carries400th Street
CrossesDrainage
Coordinates41.47809, -95.42246

Physical Characteristics

MaterialWood or Timber
DesignStringer/Multi-beam
Total Length54.1 ft (16.5 m)
Max Span23.0 ft (7 m)
Deck Width19.0 ft (5.8 m)
Deck Area95.7 sq m
Main Spans3
Year Built1948 (reconstructed 1992)

Traffic

Avg Daily Traffic40 (2021)
Lanes On Bridge2

Inspection & Ownership

Last InspectionMay 2023
Inspection FrequencyEvery 24 months
OwnerCounty Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical3 — Scour critical
Structure Number000000000289860

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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