US Bridges

US 150 over Spoon River Trib.

Fair

Knox County, Illinois · 3.8 MI W JCT 180/150 · Structure no. 048008400000000

Built
2003
22 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
95 ft
1 main span
Daily traffic
1,100
2023 count
Owner
State
State Highway Agency

About this bridge

US 150 over Spoon River Trib. is a prestressed concrete stringer/multi-beam or girder carrying US 150 over Spoon River Trib. in Knox County, Illinois. It was built in 2003, so it is 22 years old, younger than the Illinois average of 45.3 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 1,100 vehicles a day, roughly 6% of them trucks, projected to reach 1,212 by 2046. The structure is 95 ft (29 m) long and 36 ft wide. If it were closed, the detour would be 19.9 mi (32 km).

Location

Open in Google Maps
CarriesUS 150
CrossesSpoon River Trib.
Location3.8 MI W JCT 180/150
RouteU.S. Route 150
CountyKnox County
StateIllinois
Coordinates40.90869, -90.08297
Functional classRural Major 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating96.5 US tons
Inventory rating53.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length95 ft (29 m)
Longest span93 ft (28.2 m)
Deck width36 ft (11 m)
Roadway width33 ft (10 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,100 (2023)
Projected traffic1,212 by 2046
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.9 mi (32 km)
TollOn a free road
National Highway SystemNo

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—
NavigationNo navigation control on waterway

Frequently asked questions

When was US 150 over Spoon River Trib. built?

It was built in 2003, making it 22 years old in 2025.

What condition is US 150 over Spoon River Trib. 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 2023.

How much traffic does US 150 over Spoon River Trib. carry?

About 1,100 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is US 150 over Spoon River Trib.?

The structure is 95 ft (29 m) long with a longest span of 93 ft (28.2 m) and a deck 36 ft wide.

Who owns US 150 over Spoon River Trib.?

It is owned by the State Highway Agency.