US Bridges

TR-20A over Spring Creek

Poor

LaSalle County, Illinois · E 1st N 3660 · Structure no. 050344800000000

Built
1977
48 years old
Condition
Poor
inspected August 2023
Type
Channel Beam
Concrete
Length
34 ft
1 main span
Daily traffic
100
2016 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR-20A over Spring Creek is a concrete channel beam carrying TR-20A over Spring Creek in LaSalle County, Illinois. It was built in 1977, so it is 48 years old, older than the Illinois average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 3 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 100 vehicles a day, projected to reach 101 by 2046. The structure is 34 ft (10.4 m) long and 27 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesTR-20A
CrossesSpring Creek
LocationE 1st N 3660
RouteCounty Highway 0
CountyLaSalle County
StateIllinois
Coordinates41.46297, -89.14601
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.4 US tons
Inventory rating36.8 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length34 ft (10.4 m)
Longest span33 ft (10.1 m)
Deck width27 ft (8.1 m)
Roadway width25 ft (7.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2016)
Projected traffic101 by 2046
Trucks0%
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

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-20A over Spring Creek built?

It was built in 1977, making it 48 years old in 2025.

What condition is TR-20A over Spring Creek in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2023.

How much traffic does TR-20A over Spring Creek carry?

About 100 vehicles per day (2016 count).

How long is TR-20A over Spring Creek?

The structure is 34 ft (10.4 m) long with a longest span of 33 ft (10.1 m) and a deck 27 ft wide.

Who owns TR-20A over Spring Creek?

It is owned by the Town or Township Highway Agency.