US Bridges

350 Avenue over Coon Ck

FairPosted for load

Gregory County, South Dakota · 3N & 6E Burke · Structure no. 000000027180190

Built
1949
76 years old
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
201 ft
5 main spans
Daily traffic
10
2022 count
Owner
County
County Highway Agency

About this bridge

350 Avenue over Coon Ck is a steel stringer/multi-beam or girder carrying 350 Avenue over Coon Ck in Gregory County, South Dakota. It was built in 1949, so it is 76 years old, older than the South Dakota average of 48.9 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. Its operating status is: posted for load restriction.

It carries about 10 vehicles a day, roughly 2% of them trucks, projected to reach 39 by 2032. The structure is 201 ft (61.3 m) long and 22 ft wide. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
Carries350 Avenue
CrossesCoon Ck
Location3N & 6E Burke
RouteCounty Highway 0
CountyGregory County
StateSouth Dakota
Coordinates43.2261, -99.17927
Functional classRural Local

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating32.2 US tons
Inventory rating19.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length201 ft (61.3 m)
Longest span40 ft (12.1 m)
Deck width22 ft (6.8 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2022)
Projected traffic39 by 2032
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed21.7 mi (35 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost$16,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 350 Avenue over Coon Ck built?

It was built in 1949, making it 76 years old in 2025.

What condition is 350 Avenue over Coon Ck 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 350 Avenue over Coon Ck carry?

About 10 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 350 Avenue over Coon Ck?

The structure is 201 ft (61.3 m) long with a longest span of 40 ft (12.1 m) and a deck 22 ft wide.

Who owns 350 Avenue over Coon Ck?

It is owned by the County Highway Agency.