US Bridges

473 Avenue over South Fork Whetstone Rv

PoorPosted for load

Grant County, South Dakota · 5W & 0.2N Milbank · Structure no. 000000026240068

Built
1942
83 years old, rebuilt 1965
Condition
Poor
inspected August 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
35 ft
2 main spans
Daily traffic
25
2022 count
Owner
County
County Highway Agency

About this bridge

473 Avenue over South Fork Whetstone Rv is a wood or timber stringer/multi-beam or girder carrying 473 Avenue over South Fork Whetstone Rv in Grant County, South Dakota. It was built in 1942 and reconstructed in 1965, so it is 83 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 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. Its operating status is: posted for load restriction.

It carries about 25 vehicles a day, roughly 2% of them trucks, projected to reach 25 by 2032. The structure is 35 ft (10.7 m) long and 24 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Carries473 Avenue
CrossesSouth Fork Whetstone Rv
Location5W & 0.2N Milbank
RouteCounty Highway 0
Coordinates45.22589, -96.74172
Functional classRural Local

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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating13.9 US tons
Inventory rating8.7 US tons

Structure

MaterialWood or Timber
DeckWood or timber
Main spans2
Design loadUnknown
Structure length35 ft (10.7 m)
Longest span17 ft (5.2 m)
Deck width24 ft (7.4 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25 (2022)
Projected traffic25 by 2032
Trucks2%
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$600,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 473 Avenue over South Fork Whetstone Rv built?

It was built in 1942, making it 83 years old in 2025. It was reconstructed in 1965.

What condition is 473 Avenue over South Fork Whetstone Rv 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 August 2024.

How much traffic does 473 Avenue over South Fork Whetstone Rv carry?

About 25 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 473 Avenue over South Fork Whetstone Rv?

The structure is 35 ft (10.7 m) long with a longest span of 17 ft (5.2 m) and a deck 24 ft wide.

Who owns 473 Avenue over South Fork Whetstone Rv?

It is owned by the County Highway Agency.