US Bridges

C16 450th ST over Mill Creek

Good

Cherokee County, Iowa · 093412403 · Structure no. 000000000109821

Built
2019
6 years old
Condition
Good
inspected August 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
274 ft
3 main spans
Daily traffic
319
2022 count
Owner
County
County Highway Agency

About this bridge

C16 450th ST over Mill Creek is a prestressed concrete stringer/multi-beam or girder carrying C16 450th ST over Mill Creek in Cherokee County, Iowa. It was built in 2019, so it is 6 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 319 vehicles a day, roughly 28% of them trucks, projected to reach 319 by 2043. The structure is 274 ft (83.5 m) long and 33 ft wide. If it were closed, the detour would be 11.8 mi (19 km).

Location

Open in Google Maps
CarriesC16 450th ST
CrossesMill Creek
Location093412403
RouteCounty Highway 0
CountyCherokee County
StateIowa
Coordinates42.86658, -95.62544
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length274 ft (83.5 m)
Longest span102 ft (31.1 m)
Deck width33 ft (10 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic319 (2022)
Projected traffic319 by 2043
Trucks28%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.8 mi (19 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost$30,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was C16 450th ST over Mill Creek built?

It was built in 2019, making it 6 years old in 2025.

What condition is C16 450th ST over Mill Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2023.

How much traffic does C16 450th ST over Mill Creek carry?

About 319 vehicles per day (2022 count), of which roughly 28% are trucks.

How long is C16 450th ST over Mill Creek?

The structure is 274 ft (83.5 m) long with a longest span of 102 ft (31.1 m) and a deck 33 ft wide.

Who owns C16 450th ST over Mill Creek?

It is owned by the County Highway Agency.