US Bridges

SD073 over East Flat Ck

Good

Perkins County, South Dakota · 7.3 S JCT US 12 · Structure no. 000000053380083

Built
2018
7 years old
Condition
Good
inspected September 2024
Type
Culvert
Concrete Continuous
Length
34 ft
3 main spans
Daily traffic
663
2024 count
Owner
State
State Highway Agency

About this bridge

SD073 over East Flat Ck is a concrete continuous culvert carrying SD073 over East Flat Ck in Perkins County, South Dakota. It was built in 2018, so it is 7 years old, younger than the South Dakota average of 48.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 663 vehicles a day, roughly 23% of them trucks, projected to reach 991 by 2044. The structure is 34 ft (10.4 m) long. If it were closed, the detour would be 90.1 mi (145 km).

CarriesSD073
CrossesEast Flat Ck
Location7.3 S JCT US 12
RouteState Highway 73
Coordinates45.82864, -102.17682
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment9: Superior to present desirable criteria
Operating rating59.3 US tons
Inventory rating45.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadHL 93
Structure length34 ft (10.4 m)
Longest span11 ft (3.4 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic663 (2024)
Projected traffic991 by 2044
Trucks23%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed90.1 mi (145 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 SD073 over East Flat Ck built?

It was built in 2018, making it 7 years old in 2025.

What condition is SD073 over East Flat Ck in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in September 2024.

How much traffic does SD073 over East Flat Ck carry?

About 663 vehicles per day (2024 count), of which roughly 23% are trucks.

How long is SD073 over East Flat Ck?

The structure is 34 ft (10.4 m) long with a longest span of 11 ft (3.4 m).

Who owns SD073 over East Flat Ck?

It is owned by the State Highway Agency.