US Bridges

460th Avenue over Boswell Diversion Ditch

Fair

Hamlin County, South Dakota · 5.9S & 1E of Castlewood · Structure no. 000000029240109

Built
1929
96 years old
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
118 ft
5 main spans
Daily traffic
129
2022 count
Owner
County
County Highway Agency

About this bridge

460th Avenue over Boswell Diversion Ditch is a steel stringer/multi-beam or girder carrying 460th Avenue over Boswell Diversion Ditch in Hamlin County, South Dakota. It was built in 1929, so it is 96 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.

It carries about 129 vehicles a day, roughly 2% of them trucks, projected to reach 129 by 2032. The structure is 118 ft (36 m) long and 21 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries460th Avenue
CrossesBoswell Diversion Ditch
Location5.9S & 1E of Castlewood
CountyHamlin County
StateSouth Dakota
Coordinates44.64528, -97.0066
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.
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
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 alignment7: Better than present minimum criteria
Operating rating85.4 US tons
Inventory rating51.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans5
Design loadUnknown
Structure length118 ft (36 m)
Longest span23 ft (7 m)
Deck width21 ft (6.4 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic129 (2022)
Projected traffic129 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 statusEligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 460th Avenue over Boswell Diversion Ditch built?

It was built in 1929, making it 96 years old in 2025.

What condition is 460th Avenue over Boswell Diversion Ditch 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 July 2024.

How much traffic does 460th Avenue over Boswell Diversion Ditch carry?

About 129 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 460th Avenue over Boswell Diversion Ditch?

The structure is 118 ft (36 m) long with a longest span of 23 ft (7 m) and a deck 21 ft wide.

Who owns 460th Avenue over Boswell Diversion Ditch?

It is owned by the County Highway Agency.