US Bridges

Swanson RD over I-90

Fair

Winnebago County, Illinois · 1.5 MI N Ill 173 · Structure no. 101992100000000

Built
1958
67 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
232 ft
4 main spans
Daily traffic
1,950
2022 count
Owner
Toll Authority
State Toll Authority

About this bridge

Swanson RD over I-90 is a prestressed concrete stringer/multi-beam or girder carrying Swanson RD over I-90 in Winnebago County, Illinois. It was built in 1958, so it is 67 years old, older 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 1,950 vehicles a day, roughly 3% of them trucks, projected to reach 2,273 by 2046. The structure is 232 ft (70.7 m) long and 30 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

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CarriesSwanson RD
CrossesI-90
Location1.5 MI N Ill 173
CountyWinnebago County
StateIllinois
Coordinates42.3889, -88.97464
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating76.4 US tons
Inventory rating45.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans4
Design loadHS 15
Structure length232 ft (70.7 m)
Longest span66 ft (20.1 m)
Deck width30 ft (9.2 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,950 (2022)
Projected traffic2,273 by 2046
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Toll Authority
Maintained byState Toll Authority
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 Swanson RD over I-90 built?

It was built in 1958, making it 67 years old in 2025.

What condition is Swanson RD over 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 2023.

How much traffic does Swanson RD over I-90 carry?

About 1,950 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is Swanson RD over I-90?

The structure is 232 ft (70.7 m) long with a longest span of 66 ft (20.1 m) and a deck 30 ft wide.

Who owns Swanson RD over I-90?

It is owned by the State Toll Authority.