Structure 33791 · Linn County, IA

US 151 over Drainage Ditch

Carries US 151 over Drainage Ditch, 2.5 Mi. S Of Jct. U.s. 30.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure at 7 of 9.

How ratings work
Decksets the rating7/9 · Good
Superstructuresets the rating7/9 · Good
Substructure8/9 · Very Good
Channelnot part of overall9/9 · Excellent
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT141 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9 · sets the ratingSuperstructure 7/9 · sets the ratingSubstructure 8/9

141 ft end to end, longest span 55 ft. 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 slab bridge.

Built20206 years old
Length140.7 ft42.9 m
Daily traffic7,800counted 2022
Last inspectedJuly 2024every 24 months

Location

StateIowa
CountyLinn
Location2.5 Mi. S Of Jct. U.s. 30
CarriesUS 151
CrossesDrainage Ditch
Coordinates41.92669, -91.78294

Physical Characteristics

MaterialConcrete Continuous
DesignSlab
Total Length140.7 ft (42.9 m)
Max Span55.1 ft (16.8 m)
Deck Width76.1 ft (23.2 m)
Deck Area995.3 sq m
Main Spans3
Year Built2020

Traffic

Avg Daily Traffic7,800 (2022)
Truck Traffic7%
Lanes On Bridge3

Inspection & Ownership

Last InspectionJuly 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number000000000033791

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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