US Bridges

Cth N over Green Bay Tributary

Poor

Door County, Wisconsin · 0.8M N JCT Sth 57 · Structure no. P15090400000000

Built
1965
60 years old
Condition
Poor
inspected September 2024
Type
Culvert
Steel
Length
21 ft
2 main spans
Daily traffic
235
2022 count
Owner
County
County Highway Agency

About this bridge

Cth N over Green Bay Tributary is a steel culvert carrying Cth N over Green Bay Tributary in Door County, Wisconsin. It was built in 1965, so it is 60 years old, older than the Wisconsin average of 40.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 235 vehicles a day, projected to reach 258 by 2043. The structure is 21 ft (6.3 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesCth N
CrossesGreen Bay Tributary
Location0.8M N JCT Sth 57
RouteCounty Highway 0N
CountyDoor County
StateWisconsin
Coordinates44.74611, -87.67153
Functional classRural Minor Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36.4 US tons
Inventory rating21.4 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckCorrugated steel
Main spans2
Design loadH 15
Structure length21 ft (6.3 m)
Longest span8 ft (2.4 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic235 (2022)
Projected traffic258 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$154,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Cth N over Green Bay Tributary built?

It was built in 1965, making it 60 years old in 2025.

What condition is Cth N over Green Bay Tributary in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in September 2024.

How much traffic does Cth N over Green Bay Tributary carry?

About 235 vehicles per day (2022 count).

How long is Cth N over Green Bay Tributary?

The structure is 21 ft (6.3 m) long with a longest span of 8 ft (2.4 m).

Who owns Cth N over Green Bay Tributary?

It is owned by the County Highway Agency.