Alternative Fuel Corridors

Wisconsin’s Alternative Fuel Corridors promote the availability of charging and fueling stations and create eligibility for federal funding to expand charging and fueling infrastructure along those corridors.

Federal Highway Administration (FHWA) Alternative Fuel Corridor (AFC) Designation Program

The Alternative Fuel Corridor (AFC​) Designation Program was established in 2015 by 23 U.S. Code § 151 to create a national network of alternative fueling and charging infrastructure along National Highway System (NHS) corridors. This program is designed to support changes in the transportation sector that will help reduce in greenhouse gas emissions and improve the mobility of passenger and commercial vehicles that employ electric, hydrogen fuel cell, propane, and natural gas fueling technologies. Additionally, the Bipartisan Infrastructure Law (BIL), enacted as the Infrastructure Investment and Jobs Act (Public Law No: 117-58, Nov. 15, 2021), updated the requirements related to the designation of national alternative fueling corridors.

The BIL created the Discretionary Grant Program for Charging and Fueling Infrastructure, which calls for the strategic deployment of publicly accessible electric vehicle (EV) charging infrastructure, hydrogen fueling infrastructure, propane fueling infrastructure, and natural gas fueling infrastructure along designated alternative fuel corridors or in certain other locations that will be accessible to all drivers of electric vehicles, hydrogen vehicles, propane vehicles, and natural gas vehicles.

The BIL also establishes the National Electric Vehicle Infrastructure (NEVI) Formula Program to strategically deploy electric vehicle (EV) charging infrastructure along designated alternative fuel corridors. For more information on the NEVI program, please see FHWA’s NEVI Fact Sheet​. For more information on the implementation of the NEVI program in Wisconsin, visit the Wisconsin Electrification ​Initiative webpage.  

​Designations and Fuel Types

There are two designation types available for a given corridor:

  1. “Corridor-Ready”: the route has enough facilities to warrant signage indicating locations of alternative fueling stations
  2. “Corridor-Pending”: the route does not yet have enough facilities to warrant signage. FHWA coordinates with state and local entities to bring corridor-pending routes up to corridor-ready.

Designation status is based on a maximum distance between fuel stations of the same type along the corridor:

  • EV charging: EV charging facilities at 50-mile intervals along designated EV corridors.
  • Hydrogen: Hydrogen fueling facilities at 100-mile intervals along designated hydrogen corridors.
  • Propane: Propane fueling facilities at 150-mile intervals along designated propane corridors.
  • Natural gas: Compressed natural gas (CNG) and liquefied natural gas (LNG) facilities at 150-mile intervals and at 200-mile intervals respectively, along designated corridors.
There are criteria that the fueling stations need to meet to contribute towards designation status. Station criteria has changed between designation rounds, especially for EV charging. For EV stations in Round 1 Level 2 chargers were eligible to include toward corridor-ready status. Later rounds did not allow Level 2 chargers and specified the number and type of connectors at DC fast chargers. The BIL and the establishment of the NEVI program revised the criteria for distance from the corridors for EV charging stations from 5 miles to one mile and specified minimum port and power capabilities beginning in Round 6 of AFC designations. The station requirements for the three fuel types designated in Round 6 in Wisconsin are listed below.

​​Fuel Type​
​Corridor-Ready
​Corridor-Pending
​Electric Vehicle (EV)
​Public DC Fast Charging no greater than 50 miles between one station/site and the next on corridor, and no more than 1 mile from Interstate exits or highway intersections along the corridor. 

Stations should include four Combined Charging System (CCS) connectors - Type 1 ports (simultaneously charging four electric vehicles). Site power capability should be no less than 600 kW (supporting at least 150 kW per port simultaneously across 4 ports). Maximum charge power per DC port should not be below 150 kW. 
​A strategy/plan and timeline for public DC Fast Charging stations separated by more than 50 miles. 

Location of station/site- no more than 1 mile from Interstate exits or highway intersections along the corridor. 



​Liquid Propane Gas (LPG)
​Public, primary propane stations no greater than 150 miles between one station and the next on the corridor, and no more than 5 miles from Interstate exits or highway intersections along the corridor.
​Public, primary propane stations separated by more than 150 miles. 

Location of station - no more than 5 miles from Interstate exits or highway intersections along the corridor.
Compressed Natural Gas (CNG)
​Public fast fill, 3,600 psi CNG stations no greater than 150 miles between one station and the next on the corridor, and no more than 5 miles from Interstate exits or highway intersections along the corridor.
​Public fast fill, 3,600 psi CNG stations separated by more than 150 miles. 

Location of station - no more than 5 miles from Interstate exits or highway intersections along the corridor.


Designation Process

The Federal Highway Administration (FHWA) established four phases to organize designation of corridors. Rounds 1-6 (2016-2022) are completed, with the redesignation of all corridors ongoing.

  • ​Round 1: FHWA designated 55 routes across 35 states.
  • Round 2: FHWA solicited nominations from state and local officials for additional routes, expansion of originally designated routes, or additional fuel types/fuel stations along Round 1 designated routes. FHWA designated 27 routes across 8 states.
  • Round 3: FHWA designated 33 routes across 46 states.
  • Round 4: FHWA designated 24 routes across 3 states.
  • Round 5: FHWA designation 101 routes across 25 states.
  • Round 6: FHWA designated 177 EV corridor-pending and six EV corridor-ready routes across 29 states. Other alternative fuel corridor nominations resulted in the designation of nine CNG, nine LNG, 11 propane, and 30 hydrogen corridor-pending corridors, along with the designation of three CNG and four propane corridor-ready highways.

A list of all designated corridors in the United States are listed on FHWA’s website.

Wisconsin’s AFC Designations

In previous rounds FHWA has designated portions of I-90, I-94, I-39, I-41, I-43, I-535, US 151, and US 53 as Alternative Fuel Corridors. The I-94 corridor was signed in fall 2020 for electric vehicle charging between the Illinois state line and the city of Madison. See FHWA's interactive GIS maps​ for additional information on previous rounds of corridor nominations, and the U.S. Department of Energy’s Alternative Fuels Data Center for corridor and station information.

In 2022 during the sixth request for corridor nominations FHWA approved WisDOT’s nomination of parts of US 51, WIS 29, US 2, and US 141, and all of US 8 and US 41 to be designated as AFCs. Nomination of these corridors highlights WisDOT’s commitment to providing e​quit​able access to Alternative Fuel Corridors and in turn, alternative fueling and charging infrastructure, across all of Wisconsin. The map below shows corridors that are designated as pending or ready Alternative Fuel Corridors for at least one fuel type in Wisconsin.

Wisconsin Alternative Fuel Corridor Map

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