US Bridges

TR 166 B over Diamond CR

Fair

LaSalle County, Illinois · E10th RD N075 · Structure no. 050501900000000

Built
1979
46 years old
Condition
Fair
inspected June 2024
Type
Culvert
Steel
Length
27 ft
2 main spans
Daily traffic
25
2016 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR 166 B over Diamond CR is a steel culvert carrying TR 166 B over Diamond CR in LaSalle 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 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 25 vehicles a day, projected to reach 25 by 2046. The structure is 27 ft (8.1 m) long and 26 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesTR 166 B
CrossesDiamond CR
LocationE10th RD N075
RouteCounty Highway 0
CountyLaSalle County
StateIllinois
Coordinates40.93798, -88.96974
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.3 US tons
Inventory rating36.8 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadH 20
Structure length27 ft (8.1 m)
Longest span12 ft (3.6 m)
Deck width26 ft (7.9 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25 (2016)
Projected traffic25 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 TR 166 B over Diamond CR built?

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

What condition is TR 166 B over Diamond CR 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 June 2024.

How much traffic does TR 166 B over Diamond CR carry?

About 25 vehicles per day (2016 count).

How long is TR 166 B over Diamond CR?

The structure is 27 ft (8.1 m) long with a longest span of 12 ft (3.6 m) and a deck 26 ft wide.

Who owns TR 166 B over Diamond CR?

It is owned by the Town or Township Highway Agency.