US Bridges

Ia 175 over Blue Lake Creek

Fair

Monona County, Iowa · 2.1 Mi. W of I-29 · Structure no. 000000000036820

Built
1955
70 years old
Condition
Fair
inspected July 2024
Type
Slab
Concrete
Length
32 ft
1 main span
Daily traffic
1,790
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 175 over Blue Lake Creek is a concrete slab carrying Ia 175 over Blue Lake Creek in Monona County, Iowa. It was built in 1955, so it is 70 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 6 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 1,790 vehicles a day, roughly 27% of them trucks, projected to reach 1,790 by 2044. The structure is 32 ft (9.8 m) long and 35 ft wide. If it were closed, the detour would be 75.2 mi (121 km).

Location

Open in Google Maps
CarriesIa 175
CrossesBlue Lake Creek
Location2.1 Mi. W of I-29
RouteState Highway 175
CountyMonona County
StateIowa
Coordinates42.02661, -96.17571
Functional classRural 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.5 US tons
Inventory rating35.7 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length32 ft (9.8 m)
Longest span29 ft (8.8 m)
Deck width35 ft (10.6 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,790 (2022)
Projected traffic1,790 by 2044
Trucks27%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed75.2 mi (121 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ia 175 over Blue Lake Creek built?

It was built in 1955, making it 70 years old in 2025.

What condition is Ia 175 over Blue Lake 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 July 2024.

How much traffic does Ia 175 over Blue Lake Creek carry?

About 1,790 vehicles per day (2022 count), of which roughly 27% are trucks.

How long is Ia 175 over Blue Lake Creek?

The structure is 32 ft (9.8 m) long with a longest span of 29 ft (8.8 m) and a deck 35 ft wide.

Who owns Ia 175 over Blue Lake Creek?

It is owned by the State Highway Agency.