Custer County Bridge Report Card

Custer County scores 86 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

B86 / 100

Local infrastructure snapshot

Custer County, South Dakota

Custer County has 94 bridges in the National Bridge Inventory, with 5 rated poor and 1 rated scour-critical. Its poor-condition share of 5.3% is at or below the 16.1% statewide average. Poor-condition bridges carry about 1,313 daily vehicle crossings.

94Total Bridges

5Poor (5.3%)

42Fair (44.7%)

1Scour-Critical

Quote-Ready Local Facts

5.3%of county bridges are in poor condition, compared with 16.1% statewide and 6.7% nationally.

1,313daily vehicle crossings are on poor-condition bridges in the county.

1bridges are rated scour-critical, or 1.1% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Custer County a Bridge Condition Exposure Score of 86/100 (B). The county has 94 bridges in the National Bridge Inventory, including 5 in poor condition and 1 rated scour-critical. Poor-condition bridges carry about 1,313 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	5.3%	10.6
Poor-condition traffic exposure	25	1.1% of measured traffic	0.9
Scour-critical bridge share	20	1.1%	2.1
Average age vs national baseline	10	48 years vs 48 nationally	0.1
Traffic-data completeness	5	114,959 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	5.3%
State Poor-Condition Share	16.1%
National Poor-Condition Share	6.7%
County Scour-Critical Share	1.1%
Average Bridge Age	48 years
Poor-Condition Traffic Exposure	1,313 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeState Park RD over Center Lake Inlet — 1,000 vehicles/day Oldest Listed BridgeUs016a over Grace Coolidge Ck — built in 1927 All County BridgesBrowse every bridge record in Custer County.

Top Bridges to Watch in Custer County

Bridge	Reason	Condition	Daily Traffic	Year Built
State Park RD over Center Lake Inlet	Poor condition + traffic exposure	Poor	1,000	1950
E Main ST Fas 6488 over Beaver Ck	Poor condition + traffic exposure	Poor	108	1971
State Park RD over Grace Coolidge Creek	Poor condition + traffic exposure	Poor	100	1950
State Park RD over Grace Coolidge Creek	Poor condition + traffic exposure	Poor	100	1950
State Park RD over Ck	Poor condition + traffic exposure	Poor	5	1950
Us016a over Grace Coolidge Ck	Scour-critical foundation rating	Fair	1,562	1977
Us016 over French Ck	High traffic	Fair	10,052	1966
Us016 over Ck	High traffic	Good	10,052	1966
Us016a over Laughing Water Ck	High traffic	Good	6,829	1964
Sd079 over Battle Ck	High traffic	Good	6,610	1997

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.