Corson County Bridge Report Card

Corson County scores 69 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

D69 / 100

Local infrastructure snapshot

Corson County, South Dakota

Corson County has 49 bridges in the National Bridge Inventory, with 4 rated poor and 2 rated scour-critical. Its poor-condition share of 8.2% is at or below the 16.1% statewide average. Poor-condition bridges carry about 1,458 daily vehicle crossings.

49Total Bridges

4Poor (8.2%)

26Fair (53.1%)

2Scour-Critical

Quote-Ready Local Facts

8.2%of county bridges are in poor condition, compared with 16.1% statewide and 6.7% nationally.

1,458daily vehicle crossings are on poor-condition bridges in the county.

2bridges are rated scour-critical, or 4.1% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Corson County a Bridge Condition Exposure Score of 69/100 (D). The county has 49 bridges in the National Bridge Inventory, including 4 in poor condition and 2 rated scour-critical. Poor-condition bridges carry about 1,458 daily vehicle crossings. Poor condition does not mean unsafe; bridges judged unsafe are closed or restricted by transportation agencies.

Download all county report-card scores as CSV.

How the Score Breaks Down

Factor	Weight	County Value	Penalty
Poor-condition bridge share	40	8.2%	16.3
Poor-condition traffic exposure	25	8.4% of measured traffic	6.3
Scour-critical bridge share	20	4.1%	8.2
Average age vs national baseline	10	47 years vs 48 nationally	0.0
Traffic-data completeness	5	17,272 measured daily crossings	0.0

Score = 100 minus weighted penalties. The score is a comparative research signal, not an official safety rating. Read the full methodology.

County Comparisons

County Poor-Condition Share	8.2%
State Poor-Condition Share	16.1%
National Poor-Condition Share	6.7%
County Scour-Critical Share	4.1%
Average Bridge Age	47 years
Poor-Condition Traffic Exposure	1,458 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeIRR Us012 over Claymore Ck — 1,378 vehicles/day Oldest Listed Bridge104th Street over Hump Creek — built in 1930 All County BridgesBrowse every bridge record in Corson County.

Top Bridges to Watch in Corson County

Bridge	Reason	Condition	Daily Traffic	Year Built
IRR Us012 over Claymore Ck	Poor condition + traffic exposure	Poor	1,378	1958
104th Street over Hump Creek	Poor condition + traffic exposure	Poor	30	1930
Township Road over Dirt Lodge Creek	Poor condition + traffic exposure	Poor	30	1932
Corson County 35 over Grand River	Poor condition + traffic exposure	Poor	20	1990
IRR Us012 over Hay Ck	Scour-critical foundation rating	Fair	424	1962
Kenel Road over Oak Creek	Scour-critical foundation rating	Fair	156	1968
IRR Us012 over Deep Bank Ck	High traffic	Fair	1,091	1965
IRR Us012 over Br Snake Ck	High traffic	Fair	1,091	1965
IRR Us012 over Snake Ck	High traffic	Fair	1,091	1966
IRR Sd020 over Ck	High traffic	Good	956	2000

Important safety note

Poor condition does not mean a bridge is unsafe. It means at least one major component has significant deterioration and the bridge is a priority for maintenance, repair, or replacement. Bridges judged unsafe are closed or restricted by transportation agencies.