Sanborn County Bridge Report Card

Sanborn County scores 70 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

C70 / 100

Local infrastructure snapshot

Sanborn County, South Dakota

Sanborn County has 54 bridges in the National Bridge Inventory, with 7 rated poor and 0 rated scour-critical. Its poor-condition share of 13.0% is at or below the 16.1% statewide average. Poor-condition bridges carry about 578 daily vehicle crossings.

54Total Bridges

7Poor (13.0%)

29Fair (53.7%)

0Scour-Critical

Quote-Ready Local Facts

13.0%of county bridges are in poor condition, compared with 16.1% statewide and 6.7% nationally.

578daily vehicle crossings are on poor-condition bridges in the county.

0bridges are rated scour-critical, or 0.0% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Sanborn County a Bridge Condition Exposure Score of 70/100 (C). The county has 54 bridges in the National Bridge Inventory, including 7 in poor condition and 0 rated scour-critical. Poor-condition bridges carry about 578 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	13.0%	25.9
Poor-condition traffic exposure	25	3.9% of measured traffic	2.9
Scour-critical bridge share	20	0.0%	0.0
Average age vs national baseline	10	51 years vs 48 nationally	1.3
Traffic-data completeness	5	14,714 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	13.0%
State Poor-Condition Share	16.1%
National Poor-Condition Share	6.7%
County Scour-Critical Share	0.0%
Average Bridge Age	51 years
Poor-Condition Traffic Exposure	578 vehicles/day

Bridges to Watch

Busiest Poor-Condition Bridge397th Ave. over Morris Ck — 225 vehicles/day Oldest Listed Bridge225th St. over Ck — built in 1905 All County BridgesBrowse every bridge record in Sanborn County.

Top Bridges to Watch in Sanborn County

Bridge	Reason	Condition	Daily Traffic	Year Built
397th Ave. over Morris Ck	Poor condition + traffic exposure	Poor	225	1930
414th Ave. over Jim Ck	Poor condition + traffic exposure	Poor	120	1930
County RD over Sand Ck	Poor condition + traffic exposure	Poor	70	1940
220 St. over Ck	Poor condition + traffic exposure	Poor	56	1920
416th Ave. over Ck	Poor condition + traffic exposure	Poor	56	1920
397th Ave. over Sand Ck	Poor condition + traffic exposure	Poor	35	1920
241 ST over James Rv	Poor condition + traffic exposure	Poor	16	1973
Sd034 over Drainage Ditch	High traffic	Fair	1,738	1936
Sd034 W over James Rv	High traffic	Fair	1,484	2003
Sd034 E over James Rv	High traffic	Fair	1,484	2004

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.