US Bridges

Il 173 over Nippersink Cr.

Fair

McHenry County, Illinois · 2M W of IL47 · Structure no. 056009100000000

Built
2011
14 years old
Condition
Fair
inspected April 2022
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
88 ft
1 main span
Daily traffic
3,200
2023 count
Owner
State
State Highway Agency

About this bridge

Il 173 over Nippersink Cr. is a prestressed concrete stringer/multi-beam or girder carrying Il 173 over Nippersink Cr. in McHenry County, Illinois. It was built in 2011, so it is 14 years old, younger 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 3,200 vehicles a day, roughly 9% of them trucks, projected to reach 4,560 by 2046. The structure is 88 ft (26.7 m) long and 41 ft wide.

Location

Open in Google Maps
CarriesIl 173
CrossesNippersink Cr.
Location2M W of IL47
RouteState Highway 173
CountyMcHenry County
StateIllinois
Coordinates42.46261, -88.46746
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionApril 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating98.2 US tons
Inventory rating55.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length88 ft (26.7 m)
Longest span88 ft (26.7 m)
Deck width41 ft (12.6 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,200 (2023)
Projected traffic4,560 by 2046
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 Il 173 over Nippersink Cr. built?

It was built in 2011, making it 14 years old in 2025.

What condition is Il 173 over Nippersink Cr. 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 2022.

How much traffic does Il 173 over Nippersink Cr. carry?

About 3,200 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is Il 173 over Nippersink Cr.?

The structure is 88 ft (26.7 m) long with a longest span of 88 ft (26.7 m) and a deck 41 ft wide.

Who owns Il 173 over Nippersink Cr.?

It is owned by the State Highway Agency.