US Bridges

Bastian Road over Somonauk Creek

Fair

DeKalb County, Illinois · 800N 1320E · Structure no. 019540800000000

Built
1969
56 years old
Condition
Fair
inspected March 2023
Type
Channel Beam
Concrete
Length
63 ft
2 main spans
Daily traffic
100
2021 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

Bastian Road over Somonauk Creek is a concrete channel beam carrying Bastian Road over Somonauk Creek in DeKalb County, Illinois. It was built in 1969, so it is 56 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 100 vehicles a day, roughly 55% of them trucks, projected to reach 112 by 2046. The structure is 63 ft (19.3 m) long and 30 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesBastian Road
CrossesSomonauk Creek
Location800N 1320E
RouteCounty Highway 0
CountyDeKalb County
StateIllinois
Coordinates41.74762, -88.69548
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
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 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 geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.3 US tons
Inventory rating35.7 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans2
Design loadHS 20
Structure length63 ft (19.3 m)
Longest span31 ft (9.4 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2021)
Projected traffic112 by 2046
Trucks55%
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 Bastian Road over Somonauk Creek built?

It was built in 1969, making it 56 years old in 2025.

What condition is Bastian Road over 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 March 2023.

How much traffic does Bastian Road over Somonauk Creek carry?

About 100 vehicles per day (2021 count), of which roughly 55% are trucks.

How long is Bastian Road over Somonauk Creek?

The structure is 63 ft (19.3 m) long with a longest span of 31 ft (9.4 m) and a deck 30 ft wide.

Who owns Bastian Road over Somonauk Creek?

It is owned by the Town or Township Highway Agency.