US Bridges

Boyson RD over Tributary of Dry Creek

Fair

Linn County, Iowa · 084073500 · Structure no. 000000000505205

Built
1976
49 years old
Condition
Fair
inspected April 2022
Type
Culvert
Steel
Length
44 ft
3 main spans
Daily traffic
13,287
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

Boyson RD over Tributary of Dry Creek is a steel culvert carrying Boyson RD over Tributary of Dry Creek in Linn County, Iowa. It was built in 1976, so it is 49 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 13,287 vehicles a day, projected to reach 13,287 by 2043. The structure is 44 ft (13.4 m) long. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesBoyson RD
CrossesTributary of Dry Creek
Location084073500
RouteCity Street 0
CountyLinn County
StateIowa
Coordinates42.04383, -91.6229
Functional classUrban Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionApril 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.6 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans3
Design loadOther
Structure length44 ft (13.4 m)
Longest span12 ft (3.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic13,287 (2022)
Projected traffic13,287 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Boyson RD over Tributary of Dry Creek built?

It was built in 1976, making it 49 years old in 2025.

What condition is Boyson RD over Tributary of Dry Creek in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in April 2022.

How much traffic does Boyson RD over Tributary of Dry Creek carry?

About 13,287 vehicles per day (2022 count).

How long is Boyson RD over Tributary of Dry Creek?

The structure is 44 ft (13.4 m) long with a longest span of 12 ft (3.7 m).

Who owns Boyson RD over Tributary of Dry Creek?

It is owned by the City or Municipal Highway Agency.