Total Bridges
20,753
Public highway bridges in Iowa
State profile · Above national median SD
Iowa bridge safety
Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Iowa — drawn straight from the FHWA National Bridge Inventory.
- 20,753
- Public bridges
- 36.5%
- Good condition
- 20.0%
- Poor condition
- 20.0%
- Structurally deficient
Good Condition
36.5%
7,582 bridges rated 7-9
-13.5pp vs 50% benchmark
Poor Condition
20.0%
4,153 bridges rated 0-4
Structurally Deficient
20.0%
4,153 bridges flagged for repair priority
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 — Structurally deficient share 66.7%
National avg
Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.
Condition Distribution
Bridge inventory deck-condition mix — Iowa (FHWA NBI)
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 on the structurally deficient leaderboard (lower share = better)
States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below Iowa on the same metric.
54
West Virginia
16.02% top marginal rate
46
South Dakota
16.24% top marginal rate
19
Iowa
20.01% top marginal rate
78
Virgin Islands
29.17% top marginal rate
Bridges Needing Most Attention in Iowa
Six lowest-condition bridges in Iowa, ranked by composite NBI rating. Each is inspected at least every 24 months.
270TH STREET
Structurally DeficientOver: 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
Structurally DeficientOver: MUD CREEK
87-12-15-02-10, Black Hawk, IA
Built 1948 Load: 2.7 t ADT: 11
LOCAL - 700TH
Structurally DeficientOver: TRIB TROUBLESOME CREEK
077351402, Cass, IA
Built 1983 Load: 2.7 t ADT: 11
LOCAL - DAYTONA
Structurally DeficientOver: BUCK CREEK
077361903, Cass, IA
Built 1980 Load: 2.7 t ADT: 35
100TH ST.
Structurally DeficientOver: UNION CREEK
083E20101, Clinton, IA
Built 1900 Load: 2.7 t ADT: 78
All Bridges in Iowa
LOCAL (LWC)
FairOver: SMALL STREAM
085123504, Benton, IA
Built 1992 Load: 99.9 t ADT: 11
US 30
FairOver: HONEY CREEK
0.7 mi. W of Jct. SR R23, Boone, IA
Built 1962 Load: 99.9 t ADT: 8,800
US 59
FairOver: COONLEY CREEK
2.3 mi. N of SR C44, Cherokee, IA
Built 1972 Load: 99.9 t ADT: 2,460
FM
FairOver: OTTER CREEK
072241702, Clarke, IA
Built 1974 Load: 99.9 t ADT: 319
FM
FairOver: OTTER CREEK
072241702, Clarke, IA
Built 1974 Load: 99.9 t ADT: 319
LOCAL
FairOver: SMALL
072273501, Clarke, IA
Built 1977 Load: 99.9 t ADT: 26
FM
FairOver: SMALL
073260902, Clarke, IA
Built 1977 Load: 99.9 t ADT: 29
FM
FairOver: SMALL STREAM
000000000, Crawford, IA
Built 1959 Load: 99.9 t ADT: 593
FM
FairOver: STREAM
078260803, Dallas, IA
Built 1963 Load: 99.9 t ADT: 2,281
COUNTY ROAD
FairOver: CREEK
081282004, Dallas, IA
Built 1909 Load: 99.9 t ADT: 103
FM
FairOver: STREAM
068151104, Davis, IA
Built 1963 Load: 99.9 t ADT: 100
US 20
FairOver: N BRANCH CATFISH CREEK
1.7 mi. E of Jct. IA 32, Dubuque, IA
Built 1939 Load: 99.9 t ADT: 33,600
FM
FairOver: DRAINAGE
095173601, Floyd, IA
Built 1979 Load: 99.9 t ADT: 34
LOCAL
FairOver: STEWART CREEK
096162806, Floyd, IA
Built 1973 Load: 99.9 t ADT: 383
LOCAL
FairOver: DRAINAGE DITCH
087240703, Hamilton, IA
Built 1971 Load: 99.9 t ADT: 20
FM
FairOver: DRAINAGE DITCH
087253601, Hamilton, IA
Built 1976 Load: 99.9 t ADT: 509
FM
FairOver: BUCK CREEK
089252206, Hamilton, IA
Built 1975 Load: 99.9 t ADT: 199
IOWA HWY 438
FairOver: HEATHS CREEK
071061506, Henry, IA
Built 1963 Load: 99.9 t ADT: 2,290
FM
FairOver: SMALL CREEK
080170703, Jasper, IA
Built 1966 Load: 99.9 t ADT: 360
FM
FairOver: CREEK
072081502, Jefferson, IA
Built 1971 Load: 99.9 t ADT: 330
LOCAL
FairOver: STREAM
077133601, Keokuk, IA
Built 1964 Load: 99.9 t ADT: 45
2ND ST
FairOver: SMALL NATURAL STREAM
067040308, Lee, IA
Built 1959 Load: 99.9 t ADT: 3,720
FM
FairOver: CREEK
069062305, Lee, IA
Built 1958 Load: 99.9 t ADT: 150
NO MARION RD
FairOver: JUSTINS CREEK
086063004, Linn, IA
Built 1997 Load: 99.9 t ADT: 29
BLUE CREEK RD
FairOver: TRIBUTE WEST BLUE CREEK
086083110, Linn, IA
Built 2007 Load: 99.9 t ADT: 39
US 30,151,& 218
FairOver: CREEK
0.1 MI. W OF E JCT. 218, Linn, IA
Built 1975 Load: 99.9 t ADT: 28,500
HWY 99
FairOver: DRAINAGE DITCH
073020505, Louisa, IA
Built 1954 Load: 99.9 t ADT: 490
FM
FairOver: NORTH SKUNK RIVER
083202106, Marshall, IA
Built 1965 Load: 99.9 t ADT: 628
FM
FairOver: CREEK
085173402, Marshall, IA
Built 1963 Load: 99.9 t ADT: 1,483
LOCAL
FairOver: DUTCH CREEK
085431103, Monona, IA
Built 1976 Load: 99.9 t ADT: 11
LOCAL RD
FairOver: SMALL STREAM
085431403, Monona, IA
Built 1979 Load: 99.9 t ADT: 26
LOCAL ROAD
FairOver: LOCAL STREAM
071380406, Montgomery, IA
Built 1996 Load: 99.9 t ADT: 20
FM
FairOver: STREAM
071383201, Montgomery, IA
Built 1970 Load: 99.9 t ADT: 170
FM
FairOver: WALNUT CREEK TRIB
071390404, Montgomery, IA
Built 1966 Load: 99.9 t ADT: 150
FM
FairOver: SMITH RUN
076040105, Muscatine, IA
Built 1949 Load: 99.9 t ADT: 560
FM
FairOver: D.D.#125
090313602, Pocahontas, IA
Built 1987 Load: 99.9 t ADT: 240
630TH ST
FairOver: DRAINAGE DITCH 125
090313501, Pocahontas, IA
Built 1900 Load: 99.9 t ADT: 11
US 6
FairOver: LITTLE MOSQUITO CREEK
0.9 MI. E OF JCT. I-80, Pottawattamie, IA
Built 1968 Load: 99.9 t ADT: 6,500
IA 92
FairOver: STREAM
1.6 MI. E OF SR L-35, Pottawattamie, IA
Built 1953 Load: 99.9 t ADT: 5,700
E 53RD ST
FairOver: DEERE CREEK
000000000, Scott, IA
Built 1977 Load: 99.9 t ADT: 14,100
CHERRY AVE
FairOver: SMALL STREAM
094471902, Sioux, IA
Built 2000 Load: 99.9 t ADT: 20
LOCAL
FairOver: SMALL STREAM
094473602, Sioux, IA
Built 1984 Load: 99.9 t ADT: 11
LOCAL
FairOver: SMALL STREAM
095430501, Sioux, IA
Built 1999 Load: 99.9 t ADT: 15
LOCAL
FairOver: SMALL
095430502, Sioux, IA
Built 1993 Load: 99.9 t ADT: 26
LOCAL
FairOver: SMALL STREAM
095470202, Sioux, IA
Built 1934 Load: 99.9 t ADT: 11
LOCAL
FairOver: STREAM
096432102, Sioux, IA
Built 1993 Load: 99.9 t ADT: 20
LOCAL
FairOver: NO NAME CREEK
096433301, Sioux, IA
Built 1992 Load: 99.9 t ADT: 20
360TH ST
FairOver: SMALL STREAM
096452101, Sioux, IA
Built 2000 Load: 99.9 t ADT: 80
LOCAL
FairOver: SMALL STREAM
096452202, Sioux, IA
Built 2001 Load: 99.9 t ADT: 34
LOCAL
FairOver: SMALL
097431702, Sioux, IA
Built 1985 Load: 99.9 t ADT: 30
Showing 8,951-9,000 of 20,753 bridges
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.
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). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.
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.