US Bridges

Ch 6 N21st over Covel Creek

Good

LaSalle County, Illinois · 3 Mi. E. of Gr Ridge · Structure no. 050361300000000

Built
2015
10 years old
Condition
Good
inspected June 2021
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
66 ft
1 main span
Daily traffic
1,100
2023 count
Owner
County
County Highway Agency

About this bridge

Ch 6 N21st over Covel Creek is a prestressed concrete stringer/multi-beam or girder carrying Ch 6 N21st over Covel Creek in LaSalle County, Illinois. It was built in 2015, so it is 10 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 1,100 vehicles a day, roughly 12% of them trucks, projected to reach 1,616 by 2046. The structure is 66 ft (20.1 m) long and 35 ft wide. If it were closed, the detour would be 18 mi (29 km).

Location

Open in Google Maps
CarriesCh 6 N21st
CrossesCovel Creek
Location3 Mi. E. of Gr Ridge
RouteCounty Highway 0
CountyLaSalle County
StateIllinois
Coordinates41.23738, -88.77317
Functional classRural Major Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length66 ft (20.1 m)
Longest span62 ft (19 m)
Deck width35 ft (10.7 m)
Roadway width34 ft (10.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,100 (2023)
Projected traffic1,616 by 2046
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed18 mi (29 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 Ch 6 N21st over Covel Creek built?

It was built in 2015, making it 10 years old in 2025.

What condition is Ch 6 N21st over Covel Creek 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 June 2021.

How much traffic does Ch 6 N21st over Covel Creek carry?

About 1,100 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is Ch 6 N21st over Covel Creek?

The structure is 66 ft (20.1 m) long with a longest span of 62 ft (19 m) and a deck 35 ft wide.

Who owns Ch 6 N21st over Covel Creek?

It is owned by the County Highway Agency.