National Bridge Inventory: Wisconsin


  • The state has identified needed repairs on 1,746 bridges.
  • This compares to 1,815 bridges that needed work in 2021.
  • Over the life of the IIJA, Wisconsin will receive a total of $225.0 million in bridge formula funds, which will help make needed repairs.
  • Wisconsin currently has access to $180.0 million of that total, and has committed $165.8 million towards 455 projects as of June 2025.
  • Of the 14,498 bridges in the state, 976, or 6.7 percent, are classified as structurally deficient. This means one of the key elements is in poor or worse condition.
  • This is down from 987 bridges classified as structurally deficient in 2021.
  • The deck area of structurally deficient bridges accounts for 4.3 percent of total deck area on all structures.

Top Most Traveled Structurally Deficient Bridges in Wisconsin

CountyYear BuiltDaily CrossingsType of BridgeLocation
Milwaukee195979,000Urban InterstateIH 94 WB-E-W Freew over Lrd Mitchell Blvd
Milwaukee196758,500Urban InterstateIH 41/Ush 45/Sth 1 over Cth W Mill Rd (Cth S)
Milwaukee196758,500Urban InterstateIH 41/Ush 45/Sth 1 over Cth W Mill Rd (Cth S)
Dunn195935,500Rural InterstateIH 94 over E Br Wilson Creek
Milwaukee195833,971Urban other principal arterialLrd W Silver Sprin over Lincoln Creek
Marathon191528,144Urban other principal arterialLrd Stewart Ave over Wisconsin River 31
Douglas196128,098Urban InterstateI 535 over St Louis R; RR,Street
Milwaukee196326,700Urban other principal arterialLrd W Layton Ave over Sth 24-Forest Home Ave
Dane195622,500Urban other principal arterialCth M / Century Av over Pheasant Branch Creek
Milwaukee193621,845Urban minor arterialLrd N Teutonia Ave over Lincoln Creek
Dane196821,600Urban other principal arterialLrd John Nolen Dr over Lake Monona
Dane196821,600Urban other principal arterialLrd John Nolen Dr over Lake Monona
Dane196621,600Urban other principal arterialLrd John Nolen Dr over Lake Monona
Dane197521,600Urban other principal arterialLrd John Nolen Dr over Lake Monona
Dane196321,200Rural InterstateIH 94 WB over Sth 73
Eau Claire198820,800Urban other principal arterialUSH 12 over Otter Creek
Milwaukee193920,130Urban other principal arterialSth 38-Chase Ave over Cnw RR
Dane196319,150Rural InterstateIH 94 WB over Lrd Missouri Rd
Milwaukee198719,025Urban other principal arterialLrd S 43rd St over Kinnickinnick River
Milwaukee193318,735Urban minor arterialLrd 35th Street Vi over Lrd W Pierce St
Milwaukee193418,300Urban other principal arterialLrd North Ave East over Menomonee River
Milwaukee193418,300Urban other principal arterialLrd North Ave - We over Menomonee River
Milwaukee196618,200Urban InterstateIH 43 NB over Root River Marsh
Milwaukee196617,900Urban InterstateIH 43 SB-Hale Intr over Root River Marsh
St. Croix195817,800Rural InterstateIH 94 EB over Eau Galle River

Bridge Inventory: Wisconsin

Type of BridgeNumber of BridgesArea of All Bridges
(sq. meters)
Daily Crossings on All BridgesNumber of Structurally Deficient BridgesArea of Structurally Deficient Bridges
(sq. meters)
Daily Crossings on Structurally Deficient Bridges
Rural Interstate651534,67212,924,23083,239134,357
Rural arterial1,168870,9198,801,853155,24968,870
Rural minor arterial1,145545,0654,047,0693021,46876,573
Rural major collector1,811580,8382,834,00220254,300274,477
Rural minor collector735175,292646,23510418,10858,318
Rural local road5,927995,2682,053,17848856,60686,845
Urban Interstate6761,193,66023,782,978651,730260,198
Urban freeway/expressway213352,2594,843,417000
Urban other principal arterial793998,65211,879,4502823,921448,690
Urban minor arterial566621,4584,694,7703361,706232,309
Urban collector202126,671850,353205,78983,006
Urban local road611283,7792,077,5704213,44573,685
Total14,4987,278,53179,435,105976315,5611,797,328

Proposed Bridge Work

Type of WorkNumber of BridgesCost to Repair
(in millions)
Daily CrossingsArea of Bridges
(sq. meters)
Bridge replacement1,716$1,87112,075,1181,124,869
Widening & rehabilitation0$000
Rehabilitation7$5229,01247,837
Deck rehabilitation/replacement15$413,6803,049
Other structural work8$11,592880
Total1,746$1,92812,119,4021,176,634

About the data:

Data and cost estimates are from the Federal Highway Administration (FHWA) National Bridge Inventory (NBI), downloaded on June 24, 2025. Note that specific conditions on bridges may have changed as a result of recent work or updated inspections.

Effective January 1, 2018, FHWA changed the definition of structurally deficient as part of the final rule on highway and bridge performance measures, published May 20, 2017 pursuant to the 2012 federal aid highway bill Moving Ahead for Progress in the 21st Century Act (MAP-21). Two measures that were previously used to classify bridges as structurally deficient are no longer used. This includes bridges where the overall structural evaluation was rated in poor or worse condition, or where the adequacy of waterway openings was insufficient.

The new definition limits the classification to bridges where one of the key structural elements—the deck, superstructure, substructure or culverts, are rated in poor or worse condition. During inspection, the conditions of a variety of bridge elements are rated on a scale of 0 (failed condition) to 9 (excellent condition). A rating of 4 is considered “poor” condition.

Cost estimates have been derived by ARTBA, based on 2023 average bridge replacement costs for structures on and off the National Highway System, published by FHWA. Bridge rehabilitation costs are estimated to be 68 percent of replacement costs. A bridge is considered to need repair if the structure has identified repairs as part of the NBI, a repair cost estimate is supplied by the bridge owner or the bridge is classified as structurally deficient. Please note that for a few states, the number of bridges needing to be repaired can vary significantly from year to year, and reflects the data entered by the state.

Bridges are classified by FHWA into types based on the functional classification of the roadway on the bridge. Interstates comprise routes officially designated by the Secretary of Transportation. Other principal arterials serve major centers of urban areas or provide mobility through rural areas. Freeways and expressways have directional lanes generally separated by a physical barrier, and access/egress points generally limited to on- and off-ramps. Minor arterials serve smaller areas and are used for trips of moderate length. Collectors funnel traffic from local roads to the arterial network; major collectors have higher speed limits and traffic volumes and are longer in length and spaced at greater intervals, while minor collectors are shorter and provide service to smaller communities. Local roads do not carry through traffic and are intended for short distance travel.