US Bridges

TR 84A over So Br Lt Missouri

Poor

Brown County, Illinois · 4.5 MI NW Mt Sterlin · Structure no. 005371400000000

Built
1900
125 years old
Condition
Poor
inspected March 2024
Type
Truss - Thru
Steel
Length
82 ft
1 main span
Daily traffic
75
2023 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

TR 84A over So Br Lt Missouri is a steel truss - thru carrying TR 84A over So Br Lt Missouri in Brown County, Illinois. It was built in 1900, so it is 125 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 4 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 75 vehicles a day, roughly 9% of them trucks, projected to reach 51 by 2046. The structure is 82 ft (25 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesTR 84A
CrossesSo Br Lt Missouri
Location4.5 MI NW Mt Sterlin
RouteCounty Highway 0
CountyBrown County
StateIllinois
Coordinates40.05051, -90.80717
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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating36.8 US tons
Inventory rating26.8 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length82 ft (25 m)
Longest span80 ft (24.4 m)
Deck width26 ft (7.8 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic75 (2023)
Projected traffic51 by 2046
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 84A over So Br Lt Missouri built?

It was built in 1900, making it 125 years old in 2025.

What condition is TR 84A over So Br Lt Missouri 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 March 2024.

How much traffic does TR 84A over So Br Lt Missouri carry?

About 75 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is TR 84A over So Br Lt Missouri?

The structure is 82 ft (25 m) long with a longest span of 80 ft (24.4 m) and a deck 26 ft wide.

Who owns TR 84A over So Br Lt Missouri?

It is owned by the Town or Township Highway Agency.