US Bridges

300th ST over Branch Nagel Creek

Poor

Clayton County, Iowa · 092060913 · Structure no. 000000000362600

Built
1935
90 years old
Condition
Poor
inspected November 2022
Type
Truss - Thru
Steel
Length
52 ft
1 main span
Daily traffic
11
2022 count
Owner
County
County Highway Agency

About this bridge

300th ST over Branch Nagel Creek is a steel truss - thru carrying 300th ST over Branch Nagel Creek in Clayton County, Iowa. It was built in 1935, so it is 90 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 11 vehicles a day, projected to reach 11 by 2043. The structure is 52 ft (15.9 m) long and 18 ft wide.

Location

Open in Google Maps
Carries300th ST
CrossesBranch Nagel Creek
Location092060913
RouteCounty Highway 0
CountyClayton County
StateIowa
Coordinates42.79052, -91.56482
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating33.8 US tons
Inventory rating23 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length52 ft (15.9 m)
Longest span50 ft (15.2 m)
Deck width18 ft (5.5 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic11 (2022)
Projected traffic11 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 300th ST over Branch Nagel Creek built?

It was built in 1935, making it 90 years old in 2025.

What condition is 300th ST over Branch Nagel Creek in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in November 2022.

How much traffic does 300th ST over Branch Nagel Creek carry?

About 11 vehicles per day (2022 count).

How long is 300th ST over Branch Nagel Creek?

The structure is 52 ft (15.9 m) long with a longest span of 50 ft (15.2 m) and a deck 18 ft wide.

Who owns 300th ST over Branch Nagel Creek?

It is owned by the County Highway Agency.