Brookings County Bridge Report Card
Brookings County scores 50 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Brookings County, South Dakota
Brookings County has 232 bridges in the National Bridge Inventory, with 53 rated poor and 6 rated scour-critical. Its poor-condition share of 22.8% is above the 16.1% statewide average. Poor-condition bridges carry about 12,637 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Brookings County a Bridge Condition Exposure Score of 50/100 (F). The county has 232 bridges in the National Bridge Inventory, including 53 in poor condition and 6 rated scour-critical. Poor-condition bridges carry about 12,637 daily vehicle crossings. Poor condition does not mean unsafe; bridges judged unsafe are closed or restricted by transportation agencies.
How the Score Breaks Down
| Factor | Weight | County Value | Penalty |
|---|---|---|---|
| Poor-condition bridge share | 40 | 22.8% | 40.0 |
| Poor-condition traffic exposure | 25 | 4.0% of measured traffic | 3.0 |
| Scour-critical bridge share | 20 | 2.6% | 5.2 |
| Average age vs national baseline | 10 | 52 years vs 48 nationally | 1.6 |
| Traffic-data completeness | 5 | 317,957 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 | 22.8% |
| State Poor-Condition Share | 16.1% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 2.6% |
| Average Bridge Age | 52 years |
| Poor-Condition Traffic Exposure | 12,637 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Brookings County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| 471st Avenue over Br North Deer Ck | Poor condition + traffic exposure | Poor | 1,163 | 1925 |
| 471st Street over North Deer Ck | Poor condition + traffic exposure | Poor | 462 | 1925 |
| 486th Avenue over Spring Creek | Poor condition + traffic exposure | Poor | 361 | 1950 |
| 470th Avenue over Big Sioux Rv | Poor condition + traffic exposure | Poor | 1,330 | 1930 |
| 471st Avenue over Ck | Poor condition + traffic exposure | Poor | 1,305 | 1925 |
| Sd013 over Medary Ck | Poor condition + traffic exposure | Poor | 1,275 | 1938 |
| 478th Avenue over Ck | Poor condition + traffic exposure | Poor | 1,159 | 1950 |
| 478th Avenue over Deer Ck | Poor condition + traffic exposure | Poor | 712 | 1950 |
| 216th Street over Ck | Poor condition + traffic exposure | Poor | 597 | 1935 |
| 197th Street over Ck | Poor condition + traffic exposure | Poor | 345 | 1974 |
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.