US Bridges

Shabbona Grove RD over Br Somonauk Creek

Fair

DeKalb County, Illinois · 700N 1205E · Structure no. 019541000000000

Built
1961
64 years old
Condition
Fair
inspected April 2023
Type
Slab
Concrete Continuous
Length
60 ft
2 main spans
Daily traffic
50
2021 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

Shabbona Grove RD over Br Somonauk Creek is a concrete continuous slab carrying Shabbona Grove RD over Br Somonauk Creek in DeKalb County, Illinois. It was built in 1961, so it is 64 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 50 vehicles a day, projected to reach 56 by 2046. The structure is 60 ft (18.3 m) long and 29 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesShabbona Grove RD
CrossesBr Somonauk Creek
Location700N 1205E
RouteCounty Highway 0
CountyDeKalb County
StateIllinois
Coordinates41.73302, -88.71436
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.9 US tons
Inventory rating34.6 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 15
Structure length60 ft (18.3 m)
Longest span28 ft (8.5 m)
Deck width29 ft (8.8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2021)
Projected traffic56 by 2046
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerTown or Township Highway Agency
Maintained byTown or Township 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 Shabbona Grove RD over Br Somonauk Creek built?

It was built in 1961, making it 64 years old in 2025.

What condition is Shabbona Grove RD over Br Somonauk 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 April 2023.

How much traffic does Shabbona Grove RD over Br Somonauk Creek carry?

About 50 vehicles per day (2021 count).

How long is Shabbona Grove RD over Br Somonauk Creek?

The structure is 60 ft (18.3 m) long with a longest span of 28 ft (8.5 m) and a deck 29 ft wide.

Who owns Shabbona Grove RD over Br Somonauk Creek?

It is owned by the Town or Township Highway Agency.