US Bridges

Cth B over Round Lake Narrows

Fair

Sawyer County, Wisconsin · 1.0M E JCT Cth Nn · Structure no. P57092400000000

Built
1986
39 years old
Condition
Fair
inspected August 2024
Type
Slab
Wood or Timber
Length
30 ft
1 main span
Daily traffic
2,296
2024 count
Owner
County
County Highway Agency

About this bridge

Cth B over Round Lake Narrows is a wood or timber slab carrying Cth B over Round Lake Narrows in Sawyer County, Wisconsin. It was built in 1986, so it is 39 years old, younger than the Wisconsin average of 40.3 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 2,296 vehicles a day, projected to reach 2,505 by 2043. The structure is 30 ft (9.1 m) long and 36 ft wide. If it were closed, the detour would be 35.4 mi (57 km).

Location

Open in Google Maps
CarriesCth B
CrossesRound Lake Narrows
Location1.0M E JCT Cth Nn
RouteCounty Highway 0B
CountySawyer County
StateWisconsin
Coordinates45.98944, -91.31583
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
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 inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: 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 rating66.6 US tons
Inventory rating46.4 US tons

Structure

Structure typeSlab
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadHS 20
Structure length30 ft (9.1 m)
Longest span29 ft (8.8 m)
Deck width36 ft (11 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,296 (2024)
Projected traffic2,505 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed35.4 mi (57 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 Cth B over Round Lake Narrows built?

It was built in 1986, making it 39 years old in 2025.

What condition is Cth B over Round Lake Narrows 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 August 2024.

How much traffic does Cth B over Round Lake Narrows carry?

About 2,296 vehicles per day (2024 count).

How long is Cth B over Round Lake Narrows?

The structure is 30 ft (9.1 m) long with a longest span of 29 ft (8.8 m) and a deck 36 ft wide.

Who owns Cth B over Round Lake Narrows?

It is owned by the County Highway Agency.