US Bridges

ST Marys Road over Unnamed Creek

Good

Whiteside County, Illinois · 0.1 M W of Il Rt 40 · Structure no. 098555600000000

Built
1979
46 years old
Condition
Good
inspected December 2022
Type
Culvert
Concrete
Length
22 ft
2 main spans
Daily traffic
1,550
2021 count
Owner
City
City or Municipal Highway Agency

About this bridge

ST Marys Road over Unnamed Creek is a concrete culvert carrying ST Marys Road over Unnamed Creek in Whiteside County, Illinois. It was built in 1979, so it is 46 years old, older 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,550 vehicles a day, roughly 4% of them trucks, projected to reach 1,566 by 2046. The structure is 22 ft (6.6 m) long and 50 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesST Marys Road
CrossesUnnamed Creek
Location0.1 M W of Il Rt 40
RouteCity Street 0
CountyWhiteside County
StateIllinois
Coordinates41.80878, -89.69996
Functional classUrban Local

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 protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert7 GoodSome minor problems.
Last inspectionDecember 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.9 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadHS 20
Structure length22 ft (6.6 m)
Longest span10 ft (3.2 m)
Deck width50 ft (15.3 m)
Roadway width49 ft (14.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,550 (2021)
Projected traffic1,566 by 2046
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 ST Marys Road over Unnamed Creek built?

It was built in 1979, making it 46 years old in 2025.

What condition is ST Marys Road over Unnamed 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 December 2022.

How much traffic does ST Marys Road over Unnamed Creek carry?

About 1,550 vehicles per day (2021 count), of which roughly 4% are trucks.

How long is ST Marys Road over Unnamed Creek?

The structure is 22 ft (6.6 m) long with a longest span of 10 ft (3.2 m) and a deck 50 ft wide.

Who owns ST Marys Road over Unnamed Creek?

It is owned by the City or Municipal Highway Agency.