US Bridges

Koch Field RD over Rio De Flag

Good

Coconino County, Arizona · 0.4 MI N JCT T-Winona RD · Structure no. 10469

Built
1997
28 years old
Condition
Good
inspected July 2022
Type
Culvert
Steel
Length
20 ft
1 main span
Daily traffic
500
2022 count
Owner
County
County Highway Agency

About this bridge

Koch Field RD over Rio De Flag is a steel culvert carrying Koch Field RD over Rio De Flag in Coconino County, Arizona. It was built in 1997, so it is 28 years old, younger than the Arizona average of 47.8 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 500 vehicles a day, roughly 2% of them trucks, projected to reach 510 by 2042. The structure is 20 ft (6.1 m) long. If it were closed, the detour would be 29.8 mi (48 km).

Location

Open in Google Maps
CarriesKoch Field RD
CrossesRio De Flag
Location0.4 MI N JCT T-Winona RD
RouteCounty Highway 0
CountyCoconino County
StateArizona
Coordinates35.2569, -111.5248
Functional classUrban 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 inspectionJuly 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66 US tons
Inventory rating40 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadHS 20
Structure length20 ft (6.1 m)
Longest span20 ft (6.1 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic500 (2022)
Projected traffic510 by 2042
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed29.8 mi (48 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 Koch Field RD over Rio De Flag built?

It was built in 1997, making it 28 years old in 2025.

What condition is Koch Field RD over Rio De Flag 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 July 2022.

How much traffic does Koch Field RD over Rio De Flag carry?

About 500 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is Koch Field RD over Rio De Flag?

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

Who owns Koch Field RD over Rio De Flag?

It is owned by the County Highway Agency.