US Bridges

N Blue Mountain RD over Brnch of Plum River

Good

Carroll County, Illinois · 5.5 MI N Mt. Carroll · Structure no. 008311500000000

Built
2004
21 years old
Condition
Good
inspected May 2024
Type
Culvert
Concrete
Length
24 ft
4 main spans
Daily traffic
10
2021 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

N Blue Mountain RD over Brnch of Plum River is a concrete culvert carrying N Blue Mountain RD over Brnch of Plum River in Carroll County, Illinois. It was built in 2004, so it is 21 years old, younger than the Illinois average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 10 vehicles a day, projected to reach 10 by 2046. The structure is 24 ft (7.3 m) long. If it were closed, the detour would be 98.8 mi (159 km).

CarriesN Blue Mountain RD
CrossesBrnch of Plum River
Location5.5 MI N Mt. Carroll
RouteCounty Highway 0
Coordinates42.18469, -90.02308
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Culvert8 Very GoodNo problems noted.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans4
Design loadHS 20
Structure length24 ft (7.3 m)
Longest span5 ft (1.4 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 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 closed98.8 mi (159 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 Mountain RD over Brnch of Plum River built?

It was built in 2004, making it 21 years old in 2025.

What condition is N Blue Mountain RD over Brnch of Plum River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2024.

How much traffic does N Blue Mountain RD over Brnch of Plum River carry?

About 10 vehicles per day (2021 count).

How long is N Blue Mountain RD over Brnch of Plum River?

The structure is 24 ft (7.3 m) long with a longest span of 5 ft (1.4 m).

Who owns N Blue Mountain RD over Brnch of Plum River?

It is owned by the Town or Township Highway Agency.