US Bridges

Keyser RD - TR 310 over Little Mackinaw R.

Fair

Tazewell County, Illinois · SW-34-T24NR2W · Structure no. 090316800000000

Built
1972
53 years old
Condition
Fair
inspected January 2025
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
47 ft
1 main span
Daily traffic
100
2023 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

Keyser RD - TR 310 over Little Mackinaw R. is a prestressed concrete box beam or girders - multiple carrying Keyser RD - TR 310 over Little Mackinaw R. in Tazewell County, Illinois. It was built in 1972, so it is 53 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 100 vehicles a day, roughly 7% of them trucks, projected to reach 101 by 2046. The structure is 47 ft (14.3 m) long and 32 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesKeyser RD - TR 310
CrossesLittle Mackinaw R.
LocationSW-34-T24NR2W
RouteCounty Highway 0
CountyTazewell County
StateIllinois
Coordinates40.49153, -89.31899
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
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 inspectionJanuary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating74 US tons
Inventory rating46.1 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadH 15
Structure length47 ft (14.3 m)
Longest span46 ft (14 m)
Deck width32 ft (9.8 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2023)
Projected traffic101 by 2046
Trucks7%
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 Keyser RD - TR 310 over Little Mackinaw R. built?

It was built in 1972, making it 53 years old in 2025.

What condition is Keyser RD - TR 310 over Little Mackinaw R. 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 January 2025.

How much traffic does Keyser RD - TR 310 over Little Mackinaw R. carry?

About 100 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is Keyser RD - TR 310 over Little Mackinaw R.?

The structure is 47 ft (14.3 m) long with a longest span of 46 ft (14 m) and a deck 32 ft wide.

Who owns Keyser RD - TR 310 over Little Mackinaw R.?

It is owned by the Town or Township Highway Agency.