US Bridges

US20B West Bound L over Silver Creek

Fair

Stephenson County, Illinois · .5 MI E Springfld RD · Structure no. 089006000000000

Built
1987
38 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
115 ft
3 main spans
Daily traffic
6,900
2023 count
Owner
State
State Highway Agency

About this bridge

US20B West Bound L over Silver Creek is a steel continuous stringer/multi-beam or girder carrying US20B West Bound L over Silver Creek in Stephenson County, Illinois. It was built in 1987, so it is 38 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 6,900 vehicles a day, roughly 9% of them trucks, projected to reach 3,611 by 2046. The structure is 115 ft (35.2 m) long and 29 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesUS20B West Bound L
CrossesSilver Creek
Location.5 MI E Springfld RD
RouteU.S. Route 20
CountyStephenson County
StateIllinois
Coordinates42.27619, -89.53679
Functional classRural Principal Arterial - Other

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating67.5 US tons
Inventory rating40.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length115 ft (35.2 m)
Longest span45 ft (13.7 m)
Deck width29 ft (8.9 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,900 (2023)
Projected traffic3,611 by 2046
Trucks9%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was US20B West Bound L over Silver Creek built?

It was built in 1987, making it 38 years old in 2025.

What condition is US20B West Bound L over Silver Creek 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 August 2023.

How much traffic does US20B West Bound L over Silver Creek carry?

About 6,900 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is US20B West Bound L over Silver Creek?

The structure is 115 ft (35.2 m) long with a longest span of 45 ft (13.7 m) and a deck 29 ft wide.

Who owns US20B West Bound L over Silver Creek?

It is owned by the State Highway Agency.