US Bridges

I 90 over City County Drain Ditch

Fair

Yellowstone County, Montana · Billings · Structure no. I00090448+04001

Built
1966
59 years old
Condition
Fair
inspected January 2025
Type
Culvert
Steel
Length
23 ft
2 main spans
Daily traffic
27,985
2023 count
Owner
State
State Highway Agency

About this bridge

I 90 over City County Drain Ditch is a steel culvert carrying I 90 over City County Drain Ditch in Yellowstone County, Montana. It was built in 1966, so it is 59 years old, older than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 27,985 vehicles a day, roughly 14% of them trucks, projected to reach 29,804 by 2043. The structure is 23 ft (7 m) long.

Location

Open in Google Maps
CarriesI 90
CrossesCity County Drain Ditch
LocationBillings
RouteInterstate 90
CountyYellowstone County
StateMontana
Coordinates45.7522, -108.50988
Functional classUrban Principal Arterial - Interstate

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.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJanuary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadHS 20
Structure length23 ft (7 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic27,985 (2023)
Projected traffic29,804 by 2043
Trucks14%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$380,000
NavigationNo navigation control on waterway

Frequently asked questions

When was I 90 over City County Drain Ditch built?

It was built in 1966, making it 59 years old in 2025.

What condition is I 90 over City County Drain Ditch 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 January 2025.

How much traffic does I 90 over City County Drain Ditch carry?

About 27,985 vehicles per day (2023 count), of which roughly 14% are trucks.

How long is I 90 over City County Drain Ditch?

The structure is 23 ft (7 m) long with a longest span of 10 ft (3 m).

Who owns I 90 over City County Drain Ditch?

It is owned by the State Highway Agency.