US Bridges

US 136 / Il 29 over Main Ditch

Fair

Mason County, Illinois · 1.82 MI E Il 29 · Structure no. 063200000000000

Built
1958
67 years old
Condition
Fair
inspected March 2023
Type
Culvert
Concrete
Length
31 ft
3 main spans
Daily traffic
2,500
2023 count
Owner
State
State Highway Agency

About this bridge

US 136 / Il 29 over Main Ditch is a concrete culvert carrying US 136 / Il 29 over Main Ditch in Mason County, Illinois. It was built in 1958, so it is 67 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 2,500 vehicles a day, roughly 31% of them trucks, projected to reach 2,929 by 2046. The structure is 31 ft (9.5 m) long and 45 ft wide.

Location

Open in Google Maps
CarriesUS 136 / Il 29
CrossesMain Ditch
Location1.82 MI E Il 29
RouteU.S. Route 136
CountyMason County
StateIllinois
Coordinates40.30498, -89.66244
Functional classRural Principal Arterial - Other

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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
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 adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.9 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length31 ft (9.5 m)
Longest span9 ft (2.8 m)
Deck width45 ft (13.8 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,500 (2023)
Projected traffic2,929 by 2046
Trucks31%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 US 136 / Il 29 over Main Ditch built?

It was built in 1958, making it 67 years old in 2025.

What condition is US 136 / Il 29 over Main Ditch 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 March 2023.

How much traffic does US 136 / Il 29 over Main Ditch carry?

About 2,500 vehicles per day (2023 count), of which roughly 31% are trucks.

How long is US 136 / Il 29 over Main Ditch?

The structure is 31 ft (9.5 m) long with a longest span of 9 ft (2.8 m) and a deck 45 ft wide.

Who owns US 136 / Il 29 over Main Ditch?

It is owned by the State Highway Agency.