Rock County Bridge Report Card

Rock County scores 93 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

A93 / 100

Local infrastructure snapshot

Rock County, Minnesota

Rock County has 266 bridges in the National Bridge Inventory, with 5 rated poor and 3 rated scour-critical. Its poor-condition share of 1.9% is at or below the 4.5% statewide average. Poor-condition bridges carry about 3,393 daily vehicle crossings.

266Total Bridges

5Poor (1.9%)

44Fair (16.5%)

3Scour-Critical

Quote-Ready Local Facts

1.9%of county bridges are in poor condition, compared with 4.5% statewide and 6.7% nationally.

3,393daily vehicle crossings are on poor-condition bridges in the county.

3bridges are rated scour-critical, or 1.1% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Rock County a Bridge Condition Exposure Score of 93/100 (A). The county has 266 bridges in the National Bridge Inventory, including 5 in poor condition and 3 rated scour-critical. Poor-condition bridges carry about 3,393 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	1.9%	3.8
Poor-condition traffic exposure	25	1.6% of measured traffic	1.2
Scour-critical bridge share	20	1.1%	2.3
Average age vs national baseline	10	34 years vs 48 nationally	0.0
Traffic-data completeness	5	206,262 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	1.9%
State Poor-Condition Share	4.5%
National Poor-Condition Share	6.7%
County Scour-Critical Share	1.1%
Average Bridge Age	34 years
Poor-Condition Traffic Exposure	3,393 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeCsah 6 over I 90 — 1,006 vehicles/day Oldest Listed BridgeM 75 over Stream — built in 1910 All County BridgesBrowse every bridge record in Rock County.

Top Bridges to Watch in Rock County

Bridge	Reason	Condition	Daily Traffic	Year Built
Csah 6 over I 90	Poor condition + traffic exposure	Poor	1,006	1964
Csah 6 over Spring Brook	Poor condition + traffic exposure	Poor	920	1957
Csah 3 over I 90	Poor condition + traffic exposure	Poor	910	1965
Csah 8 over Mound Creek	Poor condition + traffic exposure	Poor	454	1960
Csah 19 over Stream	Poor condition + traffic exposure	Poor	103	1960
I 90 over Rock River	Scour-critical foundation rating	Fair	5,696	1965
I 90 over Rock River	Scour-critical foundation rating	Fair	5,696	1965
Csah 7 over Split Rock Creek	Scour-critical foundation rating	Fair	105	1973
I 90 over Spring Water Creek	High traffic	Fair	15,110	1960
I 90 over Elk Creek	High traffic	Fair	11,392	1964

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.