Total Bridges
20,753
Public highway bridges in Iowa
State profile · Above median Poor share
Iowa bridge safety
Condition ratings, load ratings, and Poor-condition data for every public highway bridge in Iowa, based on the FHWA National Bridge Inventory.
- 20,753
- Public bridges
- 36.5%
- Good condition
- 20.0%
- Poor condition
Data updated May 2026
Good Condition
36.5%
7,582 bridges rated 7-9
-13.5pp vs 50% benchmark
Poor Condition
20.0%
4,153 bridges whose lowest applicable component is rated 0-4
13.0pp vs national avg 7.0%
Iowa vs national bridge condition
Iowa - Good condition share 36.5%
National avg
Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).
Iowa - Poor-condition share 66.7%
National avg
Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.
Condition Distribution
Counties (99)
Adair 208 Adams 147 Allamakee 170 Appanoose 159 Audubon 161 Benton 327 Black Hawk 411 Boone 119 Bremer 220 Buchanan 281 Buena Vista 140 Butler 261 Calhoun 171 Carroll 223 Cass 237 Cedar 265 Cerro Gordo 210 Cherokee 223 Chickasaw 268 Clarke 150 Clay 138 Clayton 214 Clinton 325 Crawford 242 Dallas 154 Davis 156 Decatur 178 Delaware 254 Des Moines 156 Dickinson 73 Dubuque 304 Emmet 70 Fayette 288 Floyd 195 Franklin 214 Fremont 133 Greene 150 Grundy 270 Guthrie 236 Hamilton 134 Hancock 128 Hardin 211 Harrison 162 Henry 144 Howard 193 Humboldt 70 Ida 164 Iowa 189 Jackson 209 Jasper 321 Jefferson 142 Johnson 317 Jones 215 Keokuk 152 Kossuth 256 Lee 185 Linn 428 Louisa 134 Lucas 186 Lyon 241 Madison 221 Mahaska 219 Marion 204 Marshall 283 Mills 170 Mitchell 160 Monona 125 Monroe 126 Montgomery 184 Muscatine 127 O'Brien 229 Osceola 176 Page 185 Palo Alto 114 Plymouth 407 Pocahontas 186 Polk 415 Pottawattamie 469 Poweshiek 221 Ringgold 206 Sac 188 Scott 212 Shelby 194 Sioux 429 Story 262 Tama 307 Taylor 220 Union 153 Van Buren 142 Wapello 160 Warren 231 Washington 203 Wayne 163 Webster 179 Winnebago 48 Winneshiek 317 Woodbury 379 Worth 89 Wright 168
Iowa vs nearby ranks
Adjacent states by Poor-condition share (lower share = better)
States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Iowa on the same metric.
WV
West Virginia
16.02% top marginal rate
SD
South Dakota
16.24% top marginal rate
IA
Iowa
20.01% top marginal rate
VI
Virgin Islands
29.17% top marginal rate
Bridges Needing Most Attention in Iowa
Six lowest-condition bridges in Iowa, ranked by the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.
270TH STREET
PoorOver: ROSE BRANCH
071343401, Adams, IA
Built 1976 Load: 2.7 t ADT: 79
LOCAL
PoorOver: CREEK
078342601, Audubon, IA
Built 1935 Load: 2.7 t ADT: 21
KLINE RD
PoorOver: MUD CREEK
87-12-15-02-10, Black Hawk, IA
Built 1948 Load: 2.7 t ADT: 11
LOCAL - 700TH
PoorOver: TRIB TROUBLESOME CREEK
077351402, Cass, IA
Built 1983 Load: 2.7 t ADT: 11
LOCAL - DAYTONA
PoorOver: BUCK CREEK
077361903, Cass, IA
Built 1980 Load: 2.7 t ADT: 35
100TH ST.
PoorOver: UNION CREEK
083E20101, Clinton, IA
Built 1900 Load: 2.7 t ADT: 78
All Bridges in Iowa
NB US 218
UnknownOver: IA 3
At the Jct. of Iowa #3, Bremer, IA
Built 1996 ADT: 3,350
SB US 218
UnknownOver: IA 3
AT THE JCT. OF IA. 3, Bremer, IA
Built 1996 ADT: 3,350
IA 188
UnknownOver: US 218
At jct. US 218, Bremer, IA
Built 2002 ADT: 7,200
US 218 IA 27 NB
UnknownOver: 150TH ST
1.1 mi. S of IA 188, Bremer, IA
Built 2001 ADT: 45
US 218 IA 27 SB
UnknownOver: 150TH ST
1.1 mi. south of IA 188, Bremer, IA
Built 2001 ADT: 45
IA 3
UnknownOver: US 63
IOWA 3 OVER US 63, Bremer, IA
Built 2011 ADT: 6,400
IA 187
UnknownOver: US 20
AT JCT. OF US 20, Buchanan, IA
Built 1970 ADT: 5,700
YORK AVE
UnknownOver: US 20
1.5 MI E OF JCT. IA 187, Buchanan, IA
Built 1970 ADT: 6,500
FM V-71
UnknownOver: I 380
2.0 mi. N of S.R. D48, Buchanan, IA
Built 1983 ADT: 17,300
EB US 20
UnknownOver: IA 150
AT JCT.150, Buchanan, IA
Built 1978 ADT: 3,450
WB US 20
UnknownOver: IA 150
AT JCT. 150, Buchanan, IA
Built 1978 ADT: 3,450
W 35
UnknownOver: US 20
2.5 MI. E OF JCT. 150, Buchanan, IA
Built 1978 ADT: 8,400
SR W-40
UnknownOver: US 20
At Jct. SR W40, Buchanan, IA
Built 1978 ADT: 5,600
FM W-45
UnknownOver: US 20
3.4 mi. W of Jct. IA 187, Buchanan, IA
Built 1978 ADT: 7,000
FM V-65
UnknownOver: US 20
At Jct. US 20 & SR V65, Buchanan, IA
Built 1980 ADT: 9,100
V71
UnknownOver: US 20
6.0 MI. W OF JCT. 150, Buchanan, IA
Built 1980 ADT: 10,100
HENLEY AVE
UnknownOver: US 20
2.5 MI. W OF JCT. IA 150, Buchanan, IA
Built 1980 ADT: 10,100
IOWA AVE (MHI)
UnknownOver: US 20
1.5 MI. W OF JCT. IA 150, Buchanan, IA
Built 1980 ADT: 8,700
NB I-380
UnknownOver: SR D48
At Jct. of SR D48, Buchanan, IA
Built 1984 ADT: 575
I 380 SB
UnknownOver: D48
At jct. SR D48, Buchanan, IA
Built 1984 ADT: 575
FM W-17
UnknownOver: I-380
0.9 mi. N of Jct. SR D48, Buchanan, IA
Built 1984 ADT: 17,300
FM V-65
UnknownOver: I-380
At Jct. I-380 & S.R. V65, Buchanan, IA
Built 1984 ADT: 16,400
US 20 EB
UnknownOver: IA 4
US 20 over IA 4, Calhoun, IA
Built 2012 ADT: 1,160
US 20 WB
UnknownOver: IA 4
U.S. 20 Over IA 4, Calhoun, IA
Built 2012 ADT: 1,160
US 71
UnknownOver: UP RR & RD
0.2 mi. S of Jct. U.S. 30, Carroll, IA
Built 1988 ADT: 100
I 80 EB
UnknownOver: US 71 & BIKE TRAIL
AT JCT. U.S. 71, Cass, IA
Built 2009 ADT: 1,355
EB I-80
UnknownOver: SR N-28
AT JCT. SR N-28, Cass, IA
Built 1959 ADT: 95
740TH ST
UnknownOver: I-80
1.0 MI. W OF IA 148, Cass, IA
Built 1958 ADT: 22,500
EB I-80
UnknownOver: 770TH STREET
1.7 MI. E OF IA 148, Cass, IA
Built 1958 ADT: 8
X 30 BAKER AVE
UnknownOver: I-80
At Jct. SR X30, Cedar, IA
Built 2011 ADT: 36,200
FM
UnknownOver: I-80
3 mi. W of Jct. SR X40, Cedar, IA
Built 1960 ADT: 38,500
FM
UnknownOver: I-80
2.3 mi. E of Jct. SR X40, Cedar, IA
Built 1960 ADT: 36,900
FM Y-14
UnknownOver: I-80
2.1 mi. E of E jct. IA 38, Cedar, IA
Built 1959 ADT: 35,100
ADAMS AVE
UnknownOver: US 30
MOUNT VERNON BYPASS, Cedar, IA
Built 2020 ADT: 4,780
CO B-20
UnknownOver: I-35
3.9 MI. N OF JCT. US 18, Cerro Gordo, IA
Built 1970 ADT: 19,700
19TH STREET SW
UnknownOver: UP RR & ARMORY RD
000000000, Cerro Gordo, IA
Built 2008
JONQUIL AVE
UnknownOver: US 18 RELOC.
1.4 MI. E OF JCT. I-35, Cerro Gordo, IA
Built 1998 ADT: 8,400
US 65
UnknownOver: US 18
At Jct. US 18, Cerro Gordo, IA
Built 1996 ADT: 7,600
US 18 EB
UnknownOver: I-35
AT THE JCT. OF I-35, Cerro Gordo, IA
Built 1998 ADT: 7,800
US 18 WB
UnknownOver: I-35
AT THE JCT. OF I-35, Cerro Gordo, IA
Built 1998 ADT: 7,800
LARK AVE
UnknownOver: US 18
3.4 MI. E OF JCT. I-35, Cerro Gordo, IA
Built 1998 ADT: 8,400
CO RD B-65
UnknownOver: I-35
3.6 MI. N OF S.R. C13, Cerro Gordo, IA
Built 1972 ADT: 17,700
CO B-60
UnknownOver: I-35
AT JCT. S.R. B60, Cerro Gordo, IA
Built 1972 ADT: 17,900
FM
UnknownOver: I-35
2.0 mi. N of Jct. SR B60, Cerro Gordo, IA
Built 1972 ADT: 18,100
I 35 NB
UnknownOver: 190TH ST
4.0 mi. N of Jct. SR B60, Cerro Gordo, IA
Built 1972 ADT: 13
SB I-35
UnknownOver: 190TH ST
4.0 mi. N of Jct. SR B60, Cerro Gordo, IA
Built 1972 ADT: 13
SR B-43
UnknownOver: I-35
At Jct. of SR B43, Cerro Gordo, IA
Built 1972 ADT: 17,800
NB I-35
UnknownOver: CO RD (B-35)
2.4 MI. S OF N JCT. US 18, Cerro Gordo, IA
Built 1972 ADT: 535
I 35 SB
UnknownOver: B 35 (240TH ST)
2.4 MI. S OF N JCT. US 18, Cerro Gordo, IA
Built 1972 ADT: 535
US 18 EB
UnknownOver: WINNEBAGO RIVER & ROAD
0.6 mi. E of Jct. SR S56, Cerro Gordo, IA
Built 1998 ADT: 70
Showing 101-150 of 20,753 bridges
Related
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.
Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.
Understanding Bridge Conditions
How FHWA rates bridge condition on a 0-9 scale.
Check Your Daily Bridges
How to look up bridge condition data for bridges on your route.
Read our methodology — how this data is sourced, computed, and verified.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.