US Bridges

FM 170th Ave over Small Waterway

Good

Clay County, Iowa · 094370802 · Structure no. 000000000115971

Built
1993
32 years old
Condition
Good
inspected March 2023
Type
Culvert
Concrete
Length
20 ft
2 main spans
Daily traffic
219
2022 count
Owner
County
County Highway Agency

About this bridge

FM 170th Ave over Small Waterway is a concrete culvert carrying FM 170th Ave over Small Waterway in Clay County, Iowa. It was built in 1993, so it is 32 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 219 vehicles a day, roughly 17% of them trucks, projected to reach 219 by 2043. The structure is 20 ft (6.1 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM 170th Ave
CrossesSmall Waterway
Location094370802
RouteCounty Highway 0
CountyClay County
StateIowa
Coordinates42.97418, -95.25024
Functional classRural Minor Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating45 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadH 20
Structure length20 ft (6.1 m)
Longest span8 ft (2.4 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic219 (2022)
Projected traffic219 by 2043
Trucks17%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 170th Ave over Small Waterway built?

It was built in 1993, making it 32 years old in 2025.

What condition is FM 170th Ave over Small Waterway 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 March 2023.

How much traffic does FM 170th Ave over Small Waterway carry?

About 219 vehicles per day (2022 count), of which roughly 17% are trucks.

How long is FM 170th Ave over Small Waterway?

The structure is 20 ft (6.1 m) long with a longest span of 8 ft (2.4 m).

Who owns FM 170th Ave over Small Waterway?

It is owned by the County Highway Agency.