US Bridges

FAU-1560 (91st St) over Flag Creek

Fair

Cook County, Illinois · 0.3 M E Dupage P10 · Structure no. 016306500000000

Built
1932
93 years old, rebuilt 1981
Condition
Fair
inspected September 2024
Type
Slab
Concrete
Length
67 ft
2 main spans
Daily traffic
1,200
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

FAU-1560 (91st St) over Flag Creek is a concrete slab carrying FAU-1560 (91st St) over Flag Creek in Cook County, Illinois. It was built in 1932 and reconstructed in 1981, so it is 93 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 1,200 vehicles a day, roughly 8% of them trucks, projected to reach 1,364 by 2046. The structure is 67 ft (20.4 m) long and 56 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesFAU-1560 (91st St)
CrossesFlag Creek
Location0.3 M E Dupage P10
CountyCook County
StateIllinois
Coordinates41.72401, -87.90804
Functional classRural Minor Collector

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry8: Equal to present desirable criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating76.4 US tons
Inventory rating45.7 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans2
Design loadUnknown
Structure length67 ft (20.4 m)
Longest span32 ft (9.8 m)
Deck width56 ft (17.2 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,200 (2022)
Projected traffic1,364 by 2046
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 FAU-1560 (91st St) over Flag Creek built?

It was built in 1932, making it 93 years old in 2025. It was reconstructed in 1981.

What condition is FAU-1560 (91st St) over Flag 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 September 2024.

How much traffic does FAU-1560 (91st St) over Flag Creek carry?

About 1,200 vehicles per day (2022 count), of which roughly 8% are trucks.

How long is FAU-1560 (91st St) over Flag Creek?

The structure is 67 ft (20.4 m) long with a longest span of 32 ft (9.8 m) and a deck 56 ft wide.

Who owns FAU-1560 (91st St) over Flag Creek?

It is owned by the City or Municipal Highway Agency.