US Bridges

N Blue Mt Road over E Fork of Plum River

Fair

Carroll County, Illinois · 4 MI N Mt.Carroll · Structure no. 008310500000000

Built
1958
67 years old
Condition
Fair
inspected May 2024
Type
Channel Beam
Concrete
Length
30 ft
1 main span
Daily traffic
10
2021 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

N Blue Mt Road over E Fork of Plum River is a concrete channel beam carrying N Blue Mt Road over E Fork of Plum River in Carroll 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 10 vehicles a day, projected to reach 10 by 2046. The structure is 30 ft (9.1 m) long and 26 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

CarriesN Blue Mt Road
CrossesE Fork of Plum River
Location4 MI N Mt.Carroll
RouteCounty Highway 0
Coordinates42.15904, -89.98999
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
Deck8 Very GoodNo problems noted.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
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 rating53.2 US tons
Inventory rating31.7 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHS 15
Structure length30 ft (9.1 m)
Longest span27 ft (8.3 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2021)
Projected traffic10 by 2046
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 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 N Blue Mt Road over E Fork of Plum River built?

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

What condition is N Blue Mt Road over E Fork of Plum River 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 May 2024.

How much traffic does N Blue Mt Road over E Fork of Plum River carry?

About 10 vehicles per day (2021 count).

How long is N Blue Mt Road over E Fork of Plum River?

The structure is 30 ft (9.1 m) long with a longest span of 27 ft (8.3 m) and a deck 26 ft wide.

Who owns N Blue Mt Road over E Fork of Plum River?

It is owned by the Town or Township Highway Agency.