US Bridges

Ideal Road over Rock Creek

Fair

Carroll County, Illinois · 3 MI W Milledgeville · Structure no. 008421800000000

Built
1974
51 years old
Condition
Fair
inspected April 2023
Type
Channel Beam
Concrete
Length
86 ft
3 main spans
Daily traffic
450
2021 count
Owner
County
County Highway Agency

About this bridge

Ideal Road over Rock Creek is a concrete channel beam carrying Ideal Road over Rock Creek in Carroll County, Illinois. It was built in 1974, so it is 51 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 450 vehicles a day, roughly 7% of them trucks, projected to reach 455 by 2046. The structure is 86 ft (26.2 m) long and 30 ft wide. If it were closed, the detour would be 13 mi (21 km).

Location

Open in Google Maps
CarriesIdeal Road
CrossesRock Creek
Location3 MI W Milledgeville
RouteCounty Highway 0
CountyCarroll County
StateIllinois
Coordinates41.9737, -89.84231
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2023
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66.8 US tons
Inventory rating40 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length86 ft (26.2 m)
Longest span27 ft (8.3 m)
Deck width30 ft (9.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic450 (2021)
Projected traffic455 by 2046
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed13 mi (21 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Ideal Road over Rock Creek built?

It was built in 1974, making it 51 years old in 2025.

What condition is Ideal Road over Rock Creek 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 April 2023.

How much traffic does Ideal Road over Rock Creek carry?

About 450 vehicles per day (2021 count), of which roughly 7% are trucks.

How long is Ideal Road over Rock Creek?

The structure is 86 ft (26.2 m) long with a longest span of 27 ft (8.3 m) and a deck 30 ft wide.

Who owns Ideal Road over Rock Creek?

It is owned by the County Highway Agency.