US Bridges

186th Street over Foster Creek

PoorPosted for load

Spink County, South Dakota · 4N & 0.4W Bloomfield · Structure no. 000000058296380

Built
1915
110 years old
Condition
Poor
inspected September 2024
Type
Truss - Thru
Steel
Length
42 ft
1 main span
Daily traffic
31
2022 count
Owner
County
County Highway Agency

About this bridge

186th Street over Foster Creek is a steel truss - thru carrying 186th Street over Foster Creek in Spink County, South Dakota. It was built in 1915, so it is 110 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 3 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 31 vehicles a day, roughly 2% of them trucks, projected to reach 50 by 2032. The structure is 42 ft (12.8 m) long and 18 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Carries186th Street
CrossesFoster Creek
Location4N & 0.4W Bloomfield
RouteCounty Highway 0
Coordinates44.68993, -98.10702
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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating18 US tons
Inventory rating13.4 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length42 ft (12.8 m)
Longest span41 ft (12.5 m)
Deck width18 ft (5.5 m)
Roadway width18 ft (5.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic31 (2022)
Projected traffic50 by 2032
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.7 million (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 186th Street over Foster Creek built?

It was built in 1915, making it 110 years old in 2025.

What condition is 186th Street over Foster Creek 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 September 2024.

How much traffic does 186th Street over Foster Creek carry?

About 31 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 186th Street over Foster Creek?

The structure is 42 ft (12.8 m) long with a longest span of 41 ft (12.5 m) and a deck 18 ft wide.

Who owns 186th Street over Foster Creek?

It is owned by the County Highway Agency.