US Bridges

300th over Calmus Creek

Fair

Cerro Gordo County, Iowa · 097212801 · Structure no. 000000000106900

Built
1968
57 years old
Condition
Fair
inspected January 2024
Type
Slab
Concrete Continuous
Length
75 ft
3 main spans
Daily traffic
2,701
2022 count
Owner
County
County Highway Agency

About this bridge

300th over Calmus Creek is a concrete continuous slab carrying 300th over Calmus Creek in Cerro Gordo County, Iowa. It was built in 1968, so it is 57 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 2,701 vehicles a day, roughly 16% of them trucks, projected to reach 2,701 by 2044. The structure is 75 ft (22.9 m) long and 32 ft wide. If it were closed, the detour would be 13 mi (21 km).

Location

Open in Google Maps
Carries300th
CrossesCalmus Creek
Location097212801
RouteCounty Highway 0
CountyCerro Gordo County
StateIowa
Coordinates43.19873, -93.33135
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 2024
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
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment9: Superior to present desirable criteria
Operating rating61.4 US tons
Inventory rating36.6 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length75 ft (22.9 m)
Longest span29 ft (8.8 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,701 (2022)
Projected traffic2,701 by 2044
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed13 mi (21 km)
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 over Calmus Creek built?

It was built in 1968, making it 57 years old in 2025.

What condition is 300th over Calmus 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 January 2024.

How much traffic does 300th over Calmus Creek carry?

About 2,701 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is 300th over Calmus Creek?

The structure is 75 ft (22.9 m) long with a longest span of 29 ft (8.8 m) and a deck 32 ft wide.

Who owns 300th over Calmus Creek?

It is owned by the County Highway Agency.