US Bridges

Il 121 over Fork Deer Creek

Good

Logan County, Illinois · 2.7M S Il 10 · Structure no. 054203400000000

Built
1998
27 years old
Condition
Good
inspected May 2024
Type
Culvert
Concrete Continuous
Length
39 ft
3 main spans
Daily traffic
3,650
2023 count
Owner
State
State Highway Agency

About this bridge

Il 121 over Fork Deer Creek is a concrete continuous culvert carrying Il 121 over Fork Deer Creek in Logan County, Illinois. It was built in 1998, so it is 27 years old, younger than the Illinois average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 3,650 vehicles a day, roughly 16% of them trucks, projected to reach 3,833 by 2046. The structure is 39 ft (11.8 m) long. If it were closed, the detour would be 19.3 mi (31 km).

CarriesIl 121
CrossesFork Deer Creek
Location2.7M S Il 10
RouteState Highway 121
Coordinates40.1147, -89.33099
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert8 Very GoodNo problems noted.
Last inspectionMay 2024
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.2 US tons
Inventory rating37.8 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadHS 20
Structure length39 ft (11.8 m)
Longest span12 ft (3.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,650 (2023)
Projected traffic3,833 by 2046
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.3 mi (31 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 Il 121 over Fork Deer Creek built?

It was built in 1998, making it 27 years old in 2025.

What condition is Il 121 over Fork Deer Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2024.

How much traffic does Il 121 over Fork Deer Creek carry?

About 3,650 vehicles per day (2023 count), of which roughly 16% are trucks.

How long is Il 121 over Fork Deer Creek?

The structure is 39 ft (11.8 m) long with a longest span of 12 ft (3.7 m).

Who owns Il 121 over Fork Deer Creek?

It is owned by the State Highway Agency.