US Bridges

Il 29 (nb) over S Fk Sangamon River

Fair

Sangamon County, Illinois · 2.4M SE I-55 Intchg · Structure no. 084004200000000

Built
1963
62 years old, rebuilt 1999
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
353 ft
5 main spans
Daily traffic
13,500
2023 count
Owner
State
State Highway Agency

About this bridge

Il 29 (nb) over S Fk Sangamon River is a steel continuous stringer/multi-beam or girder carrying Il 29 (nb) over S Fk Sangamon River in Sangamon County, Illinois. It was built in 1963 and reconstructed in 1999, so it is 62 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 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 13,500 vehicles a day, roughly 9% of them trucks, projected to reach 6,161 by 2046. The structure is 353 ft (107.6 m) long and 37 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesIl 29 (nb)
CrossesS Fk Sangamon River
Location2.4M SE I-55 Intchg
RouteState Highway 29
CountySangamon County
StateIllinois
Coordinates39.76403, -89.56226
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating93.9 US tons
Inventory rating56.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length353 ft (107.6 m)
Longest span74 ft (22.7 m)
Deck width37 ft (11.3 m)
Roadway width34 ft (10.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic13,500 (2023)
Projected traffic6,161 by 2046
Trucks9%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$1.3 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Il 29 (nb) over S Fk Sangamon River built?

It was built in 1963, making it 62 years old in 2025. It was reconstructed in 1999.

What condition is Il 29 (nb) over S Fk Sangamon River 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 November 2024.

How much traffic does Il 29 (nb) over S Fk Sangamon River carry?

About 13,500 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is Il 29 (nb) over S Fk Sangamon River?

The structure is 353 ft (107.6 m) long with a longest span of 74 ft (22.7 m) and a deck 37 ft wide.

Who owns Il 29 (nb) over S Fk Sangamon River?

It is owned by the State Highway Agency.