Polk County Bridge Report Card

Polk County scores 85 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

B85 / 100

Local infrastructure snapshot

Polk County, Iowa

Polk County has 548 bridges in the National Bridge Inventory, with 34 rated poor and 5 rated scour-critical. Its poor-condition share of 6.2% is at or below the 18.6% statewide average. Poor-condition bridges carry about 80,825 daily vehicle crossings.

548Total Bridges

34Poor (6.2%)

195Fair (35.6%)

5Scour-Critical

Quote-Ready Local Facts

6.2%of county bridges are in poor condition, compared with 18.6% statewide and 6.7% nationally.

80,825daily vehicle crossings are on poor-condition bridges in the county.

5bridges are rated scour-critical, or 0.9% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Polk County a Bridge Condition Exposure Score of 85/100 (B). The county has 548 bridges in the National Bridge Inventory, including 34 in poor condition and 5 rated scour-critical. Poor-condition bridges carry about 80,825 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	6.2%	12.4
Poor-condition traffic exposure	25	1.2% of measured traffic	0.9
Scour-critical bridge share	20	0.9%	1.8
Average age vs national baseline	10	39 years vs 48 nationally	0.0
Traffic-data completeness	5	6,595,352 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	6.2%
State Poor-Condition Share	18.6%
National Poor-Condition Share	6.7%
County Scour-Critical Share	0.9%
Average Bridge Age	39 years
Poor-Condition Traffic Exposure	80,825 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeFleur DR over Old Up Rr & SW 22nd — 15,634 vehicles/day Oldest Listed BridgeST Johns RD over Drainage — built in 1900 All County BridgesBrowse every bridge record in Polk County.

Top Bridges to Watch in Polk County

Bridge	Reason	Condition	Daily Traffic	Year Built
NE 38th ST over Drainage Ditch	Poor condition + traffic exposure	Poor	459	1914
Fleur DR over Old Up Rr & SW 22nd	Poor condition + traffic exposure	Poor	15,634	1936
SW 9th ST over Cherry Rr Mlk PKWY	Poor condition + traffic exposure	Poor	14,108	1967
SW 9th ST over Raccoon River & Trail	Poor condition + traffic exposure	Poor	12,809	1967
SE 6th ST over Des Moines River	Poor condition + traffic exposure	Poor	7,911	1976
SW 8th ST over Rr Cherry Mlk Jr PKWY	Poor condition + traffic exposure	Poor	6,875	1967
SE 5th ST over Yeader Creek	Poor condition + traffic exposure	Poor	4,717	1976
Williams ST over Four Mile Creek	Poor condition + traffic exposure	Poor	3,908	1978
Walnut ST over Des Moines River	Poor condition + traffic exposure	Poor	3,844	1911
Grant ST South over Mud Creek	Poor condition + traffic exposure	Poor	2,902	1927

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.