US Bridges

Preserve RD over Somonauk Creek

Fair

DeKalb County, Illinois · 900N 1165E · Structure no. 019530200000000

Built
1951
74 years old
Condition
Fair
inspected February 2023
Type
Tee Beam
Concrete
Length
32 ft
1 main span
Daily traffic
50
2021 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

Preserve RD over Somonauk Creek is a concrete tee beam carrying Preserve RD over Somonauk Creek in DeKalb County, Illinois. It was built in 1951, so it is 74 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 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 50 vehicles a day, projected to reach 56 by 2046. The structure is 32 ft (9.8 m) long and 27 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesPreserve RD
CrossesSomonauk Creek
Location900N 1165E
RouteCounty Highway 0
CountyDeKalb County
StateIllinois
Coordinates41.76184, -88.72422
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 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 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 rating56.8 US tons
Inventory rating30.3 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length32 ft (9.8 m)
Longest span31 ft (9.4 m)
Deck width27 ft (8.2 m)
Roadway width22 ft (6.6 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 closed3.1 mi (5 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 Preserve RD over Somonauk Creek built?

It was built in 1951, making it 74 years old in 2025.

What condition is Preserve RD 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 February 2023.

How much traffic does Preserve RD over Somonauk Creek carry?

About 50 vehicles per day (2021 count).

How long is Preserve RD over Somonauk Creek?

The structure is 32 ft (9.8 m) long with a longest span of 31 ft (9.4 m) and a deck 27 ft wide.

Who owns Preserve RD over Somonauk Creek?

It is owned by the Town or Township Highway Agency.