US Bridges

S 200 over Int Bonner I 90

Fair

Missoula County, Montana · 1M W Bonner · Structure no. P00024000+00001

Built
1965
60 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
244 ft
4 main spans
Daily traffic
8,302
2023 count
Owner
State
State Highway Agency

About this bridge

S 200 over Int Bonner I 90 is a prestressed concrete stringer/multi-beam or girder carrying S 200 over Int Bonner I 90 in Missoula County, Montana. It was built in 1965, so it is 60 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 8,302 vehicles a day, roughly 3% of them trucks, projected to reach 8,717 by 2043. The structure is 244 ft (74.3 m) long and 31 ft wide.

Location

Open in Google Maps
CarriesS 200
CrossesInt Bonner I 90
Location1M W Bonner
RouteState Highway 200
CountyMissoula County
StateMontana
Coordinates46.87668, -113.89341
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Approach roadway alignment7: Better than present minimum criteria
Operating rating47 US tons
Inventory rating24 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length244 ft (74.3 m)
Longest span70 ft (21.3 m)
Deck width31 ft (9.4 m)
Roadway width28 ft (8.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,302 (2023)
Projected traffic8,717 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was S 200 over Int Bonner I 90 built?

It was built in 1965, making it 60 years old in 2025.

What condition is S 200 over Int Bonner I 90 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 June 2024.

How much traffic does S 200 over Int Bonner I 90 carry?

About 8,302 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is S 200 over Int Bonner I 90?

The structure is 244 ft (74.3 m) long with a longest span of 70 ft (21.3 m) and a deck 31 ft wide.

Who owns S 200 over Int Bonner I 90?

It is owned by the State Highway Agency.