US Bridges

Kolb Road over Drainageway

Fair

Pima County, Arizona · 0.2 MI S of I 10 · Structure no. 08893

Built
1985
40 years old
Condition
Fair
inspected November 2023
Type
Culvert
Steel
Length
21 ft
4 main spans
Daily traffic
7,191
2023 count
Owner
County
County Highway Agency

About this bridge

Kolb Road over Drainageway is a steel culvert carrying Kolb Road over Drainageway in Pima County, Arizona. It was built in 1985, so it is 40 years old, younger than the Arizona average of 47.8 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 7,191 vehicles a day, roughly 1% of them trucks, projected to reach 7,201 by 2042. The structure is 21 ft (6.4 m) long and 40 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

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CarriesKolb Road
CrossesDrainageway
Location0.2 MI S of I 10
RouteCounty Highway 0
CountyPima County
StateArizona
Coordinates32.09873, -110.84112
Functional classUrban Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
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 rating54 US tons
Inventory rating32 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans4
Design loadHS 20
Structure length21 ft (6.4 m)
Longest span4 ft (1.2 m)
Deck width40 ft (12.2 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,191 (2023)
Projected traffic7,201 by 2042
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemYes

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 Kolb Road over Drainageway built?

It was built in 1985, making it 40 years old in 2025.

What condition is Kolb Road over Drainageway 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 November 2023.

How much traffic does Kolb Road over Drainageway carry?

About 7,191 vehicles per day (2023 count), of which roughly 1% are trucks.

How long is Kolb Road over Drainageway?

The structure is 21 ft (6.4 m) long with a longest span of 4 ft (1.2 m) and a deck 40 ft wide.

Who owns Kolb Road over Drainageway?

It is owned by the County Highway Agency.