In late May 2024, a blue-and-silver Amtrak trainset eased out of St. Paul's Union Depot bound for Chicago, retracing a route that trains have run, in one form or another, since the 1850s. There was ribbon-cutting. There were speeches. And then, quietly, the Borealis did something that transit planners talk about but rarely get to witness in real time: it doubled a corridor's daily service and watched the ridership curve go nearly vertical.
Two years later, the numbers are in, and they are striking enough that they've become a live exhibit in the fight over what comes after the Bipartisan Infrastructure Law. More than 416,000 people have ridden the Borealis in its first two years. The full Chicago–Milwaukee–Twin Cities corridor — Borealis, Empire Builder, and Hiawatha combined — is up 27% to roughly 1.8 million riders. And in a stat that has been widely cited in Congressional hearings and FRA planning documents, corridor ridership jumped 227% year-over-year in the first full year of Borealis service — a comparison of FY25's full-year ridership to the partial-launch FY24 baseline — against the pre-Borealis single-train numbers.
All of that from adding one daily round trip.
The Frequency Effect, Explained
Transit economists have a name for what just happened between St. Paul and Chicago: the frequency effect. The short version is that ridership doesn't scale linearly with service. It scales super-linearly. Double the trains, and you don't just get double the riders — you get more, sometimes much more, because a second departure transforms the kind of trip the service can serve.
Before Borealis, the corridor had exactly one daily train: the Empire Builder, a long-distance service that rolls through Milwaukee and La Crosse on its way from Chicago to Seattle. If the Empire Builder's schedule didn't fit your trip — and for most business travelers, weekend visitors, or anyone with a same-day return in mind, it didn't — Amtrak simply wasn't an option. You drove.
Adding a second daily frequency didn't just give people another train. It gave them a choice of trains. You can now leave St. Paul in the morning and be in Chicago in time for dinner, or leave Chicago after work and be home in Milwaukee before the news. That's not a marginal improvement; it's a different product.
Amtrak EVP Jennifer Mitchell put it plainly at the two-year anniversary: "People want another choice besides driving, and offering service multiple times daily supercharges the number of customers who choose Amtrak because our schedules fit their needs. We look forward to adding more seating capacity and more service in this corridor in the months and years to come."
That "more seating capacity" line is worth flagging. The Borealis currently runs on Amtrak's legacy Superliner and Horizon equipment. The next-generation Amtrak Airo trainsets from Siemens Mobility — already in service on the Cascades and headed to the Northeast Regional and a dozen-plus other routes — have not been officially announced for the Borealis. Midwest rail advocates have interpreted Mitchell's phrasing as a signal that Airo equipment could eventually come to this corridor, though that remains speculative.
Where the Riders Are Coming From
The station-level data tells you which parts of the frequency effect are working hardest. In the first 11 months of service (May 2024 through April 2025), Chicago Union Station handled 128,797 Borealis boardings and alightings — more than double the 56,445 total Amtrak passengers who used Chicago on the corridor's previous, single-train year. St. Paul went from 44,553 to 106,581. Milwaukee, the corridor's largest intermediate stop, drew 70,607 Borealis riders on top of its existing Hiawatha traffic to Chicago.
The most interesting numbers, though, are the small ones. Milwaukee Airport — a brand-new Amtrak station that didn't exist as a stop before Borealis — pulled in 11,333 riders. Sturtevant, another first-time Amtrak community, joined the network the same day. La Crosse hit 20,716; Wisconsin Dells, 11,311. These are the numbers that back up WisDOT Secretary Kristina Boardman's assessment: "It provides a transportation alternative for people living in smaller Wisconsin communities and a new way for Wisconsinites to explore big cities like Milwaukee, Chicago, and the Twin Cities."
That's the part of the intercity rail story that gets underweighted in coverage focused on the Northeast Corridor. Trains are one of the few modes that can serve a metropolis and a town of 10,000 with the same vehicle, on the same schedule, at the same price point. It's a rare form of genuine rural and small-city access.
How State-Supported Corridors Actually Work
The Borealis isn't a federal project in the way people sometimes imagine Amtrak. It's a state-supported route, which is a specific and increasingly important animal in the American passenger-rail ecosystem. Amtrak now operates 29 state-supported routes in partnership with 18 states.
The model splits the bill three ways. States — in this case Minnesota, Wisconsin, and Illinois, through MnDOT, WisDOT, and IDOT — cover the operating costs. The Federal Railroad Administration, through IIJA-funded grant programs, pays for the capital side: track upgrades, station work, equipment. Amtrak actually runs the trains and, critically, negotiates with the host freight railroad — here CPKC, the merged Canadian Pacific Kansas City network that owns the former Milwaukee Road main line the Borealis uses.
That three-way structure is why the Borealis matters beyond the Midwest. It's a working template. FRA's Corridor Identification Program is currently evaluating dozens of prospective new corridors around the country, and the Borealis is the case study everyone points to when the question comes up: does this model actually produce ridership?
The answer, so far, is yes — emphatically. All three partner states have voiced their enthusiasm. MnDOT Commissioner Nancy Daubenberger noted, "We are so pleased the Borealis continues to operate at capacity… We look forward to continuing the positive partnerships with WisDOT, IDOT and Amtrak, to potentially grow and expand on this much-needed service." Illinois Transportation Secretary Gia Biagi echoed that sentiment, calling the Borealis a model for how state-federal partnerships can deliver real transportation options for travelers across the Midwest. And WisDOT's Boardman has already been quoted above on what it means for smaller Wisconsin communities.
Small Stations, Real Money
The federal side of the partnership is visible in places you wouldn't expect. In Columbus, Wisconsin, a $6.3 million project delivered two new 350-foot concrete ADA-compliant platforms and LED lighting at a station originally built in 1906. In Tomah, another $5 million produced a 330-foot heated concrete platform with full ADA compliance at a station dating to 1903 and eligible for the National Register of Historic Places. Both towns have had continuous passenger rail service since the 1850s. They've never had platforms this good.
Those Columbus and Tomah upgrades are part of a much larger federal push: Amtrak invested $182 million in ADA compliance across its national network in FY25 alone, on the way to a target of 100% ADA-compliant stations by 2029. The Borealis corridor is both a beneficiary of and an argument for that investment.
The Bigger Amtrak Story
The Borealis is riding a broader wave. In fiscal year 2025, Amtrak set an all-time record with 34.5 million passenger trips (up 5.1% year-over-year), cracked $2.7 billion in adjusted ticket revenue for the first time in its history, and logged 6.9 billion passenger-miles. Total operating revenue hit $3.9 billion, up 9.1%. Capital investment climbed approximately 25% to $5.5 billion. The railroad is now, credibly, on track for train operational profitability by FY28 — a phrase that would have sounded like fantasy a decade ago.
State-supported routes are doing a lot of the work. Amtrak specifically called out Borealis, the Pacific Surfliner, Amtrak Cascades, and Empire Service as posting "record gains" in FY25.
Cars Off the Road, Dollars Off the Ledger
The environmental and fiscal case for the Borealis is more concrete than the usual rail advocacy talking points. A Rail Passengers Association analysis, extrapolated from earlier corridor studies, estimates that about 60% of Borealis passengers are diverting from car trips — roughly 90,000 fewer car trips per year on I-94 and its parallel state routes, translating to an estimated $32 million per year in avoided highway maintenance costs. That aligns neatly with what we know about the true cost of road maintenance versus transit: highways are expensive to keep flat, and every trip diverted is money the state doesn't have to spend on asphalt.
Rail Passengers Association CEO Jim Mathews framed it in bigger terms: "Passenger trains mean trips that are taken off of highways and out of the sky, saving lives, limiting pollution, and opening up new possibilities."
It's worth naming this for what it is: a genuinely positive story in a transit landscape that's mostly been grim news lately. That doesn't mean the tradeoffs vanish — the Borealis still depends on CPKC dispatching, still runs on aging equipment, and still needs state general funds every year to stay on the rails. But on the merits, the ledger is unusually clean.
The Reauthorization Fight
Which brings us to the political context nobody in the rail world can stop thinking about. The Bipartisan Infrastructure Law — the source of the FRA grants that made Borealis station upgrades and the Corridor ID program possible — expires on September 30, 2026. The House Transportation and Infrastructure Committee has advanced the BUILD America 250 Act, a five-year surface transportation reauthorization bill. The Senate has its own ideas. And the clock is ticking toward a very real transit fiscal cliff if agreement isn't reached.
But the details matter — and they're alarming for rail advocates. Critics in the rail community note that the BUILD America 250 Act zeroes out guaranteed rail funding entirely, cutting rail investment approximately 43% versus IIJA's dedicated rail grant programs. That's a direct threat to the very FRA corridor model the Borealis exemplifies: no dedicated capital grants means no Columbus platform upgrades, no Tomah station rehabs, and no Corridor ID Program funding for the next generation of Borealis-style expansions.
FRA Administrator David Fink was direct at the two-year mark: "The Borealis line is a testament to what happens when we prioritize the American traveler. FRA is working with Amtrak and our state partners to usher in the Golden Age of Rail with world-class connectivity and economic growth."
Whether you buy the "Golden Age" framing or not, the argument writes itself. One additional daily train, funded through a three-state partnership and federal capital grants, produced a 227% corridor ridership surge, took 90,000 cars off the highway, and gave a dozen small Wisconsin towns a real transportation alternative for the first time in a generation. If a reauthorized law can replicate that outcome across even a handful of the corridors FRA is currently studying, the return on federal dollars will be extraordinary. The question is whether Congress will preserve the funding mechanism that made it possible.
That's the Borealis effect. Two years in, it's not a theory anymore. It's a train schedule.