US Bridges

170 ST over Mid Tarkio CR

Good

Atchison County, Missouri · S 31 T 66 N R 37 W · Structure no. 16541

Built
1996
29 years old
Condition
Good
inspected February 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
121 ft
3 main spans
Daily traffic
15
2024 count
Owner
County
County Highway Agency

About this bridge

170 ST over Mid Tarkio CR is a steel stringer/multi-beam or girder carrying 170 ST over Mid Tarkio CR in Atchison County, Missouri. It was built in 1996, so it is 29 years old, younger than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 15 vehicles a day, roughly 10% of them trucks, projected to reach 17 by 2044. The structure is 121 ft (36.9 m) long and 23 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
Carries170 ST
CrossesMid Tarkio CR
LocationS 31 T 66 N R 37 W
RouteCounty Highway 124
CountyAtchison County
StateMissouri
Coordinates40.48079, -95.36398
Functional classRural Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionFebruary 2024
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating24.8 US tons
Inventory rating14.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadOther
Structure length121 ft (36.9 m)
Longest span60 ft (18.3 m)
Deck width23 ft (6.9 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15 (2024)
Projected traffic17 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 170 ST over Mid Tarkio CR built?

It was built in 1996, making it 29 years old in 2025.

What condition is 170 ST over Mid Tarkio CR 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 February 2024.

How much traffic does 170 ST over Mid Tarkio CR carry?

About 15 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is 170 ST over Mid Tarkio CR?

The structure is 121 ft (36.9 m) long with a longest span of 60 ft (18.3 m) and a deck 23 ft wide.

Who owns 170 ST over Mid Tarkio CR?

It is owned by the County Highway Agency.