Mason County Bridge Report Card

Mason County scores 78 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

C78 / 100

Local infrastructure snapshot

Mason County, Michigan

Mason County has 66 bridges in the National Bridge Inventory, with 4 rated poor and 3 rated scour-critical. Its poor-condition share of 6.1% is at or below the 11.0% statewide average. Poor-condition bridges carry about 774 daily vehicle crossings.

66Total Bridges

4Poor (6.1%)

41Fair (62.1%)

3Scour-Critical

Quote-Ready Local Facts

6.1%of county bridges are in poor condition, compared with 11.0% statewide and 6.7% nationally.

774daily vehicle crossings are on poor-condition bridges in the county.

3bridges are rated scour-critical, or 4.5% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Mason County a Bridge Condition Exposure Score of 78/100 (C). The county has 66 bridges in the National Bridge Inventory, including 4 in poor condition and 3 rated scour-critical. Poor-condition bridges carry about 774 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	6.1%	12.1
Poor-condition traffic exposure	25	0.5% of measured traffic	0.4
Scour-critical bridge share	20	4.5%	9.1
Average age vs national baseline	10	49 years vs 48 nationally	0.3
Traffic-data completeness	5	149,490 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	6.1%
State Poor-Condition Share	11.0%
National Poor-Condition Share	6.7%
County Scour-Critical Share	4.5%
Average Bridge Age	49 years
Poor-Condition Traffic Exposure	774 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeCleveland ST over N Br Lincoln River — 425 vehicles/day Oldest Listed BridgeLakeshore Drive over Bass Lake Outlet — built in 1900 All County BridgesBrowse every bridge record in Mason County.

Top Bridges to Watch in Mason County

Bridge	Reason	Condition	Daily Traffic	Year Built
Younkers Road over Big Sauble River	Poor condition + traffic exposure	Poor	49	1960
Cleveland ST over N Br Lincoln River	Poor condition + traffic exposure	Poor	425	1960
Tyndall Road over Big Sable River	Poor condition + traffic exposure	Poor	200	1900
Wilson Road over S Br Pere Marquette Rivr	Poor condition + traffic exposure	Poor	100	1900
Us-31 over Big Sable River	Scour-critical foundation rating	Fair	6,578	1959
First Street over Black River	Scour-critical foundation rating	Fair	312	1998
Old Us-31 over Csx Rr	High traffic	Good	11,200	1935
Old Us-31 over Durham Creek	High traffic	Fair	8,600	1925
Old Us-31 over Pere Marquette River	High traffic	Fair	7,076	1925
Old Us-31 over Pere Marquette River	High traffic	Fair	6,828	1924

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.