Photo by Mariusz Pierog on Unsplash
If you’ve ridden a Divvy bike in Chicago at any point over the last five years, you’ve undoubtedly braved some type of construction. Orange construction barrels on Milwaukee, freshly painted sharrows (shared-lane markings) on residential side streets, those white plastic flex-posts on Dearborn that are supposed to make you feel separated from a turning SUV… you get the picture. Though all this construction might have felt random at times, the truth is that much of it was tied to a concerted effort to improve the city’s bike infrastructure. Over those five years the Divvy footprint more than doubled, the city laid down 100-plus miles of new bike lanes, and the investment was real by any honest measure. So a fair question: did any of it actually change how you ride, or how safely you get home?
To figure this out we pulled 32 million Divvy bike trips, every Chicago bicycle crash record since 2020, and the install date for nearly every new bike lane segment in the city. We tested whether the new infrastructure moved ridership as well as its impact on safety. With that grounding, we built a priority index that scores 4,473 Chicago street corridors on where the next bike lane should go.
The honest answer to “did it change anything?” turns out to depend on what you measure, where you look, and which kind of bike lane you’re talking about. Here’s what we found.
A quick note on scope. Every ridership number in this piece is Divvy bike trips only. Divvy’s reported 2024 total of around 6.7 million includes electric scooters; our 5.8 million is bikes only. Crash counts are bicycle crashes only and exclude fatalities. Methodology and sources are at the bottom.
Commuters and cruisers
Before any of that matters, you need to know who is actually on the bikes. Divvy is two systems sharing one fleet. Members buy annual subscriptions and ride almost daily — they’re the commuters. Casual riders pay per trip or buy a day pass — the tourists, the weekend experimenters, the people borrowing a bike once to see the lakefront.
The volume tells you the first part. Members have taken about 19.8 million bike trips since 2020, casual riders about 12.6 million. That’s a 61/39 split, and it has barely moved year over year. Members carry the system while casual riders fill in the warm months.
The seasonal swing is dramatic: a factor of 5.2 between January troughs and September peaks. But the two groups don’t swing equally. In summer, casual volume converges close to member levels, narrowing the gap to nearly even. In winter, that gap blows open — members keep pedaling at meaningful volume while casual ridership drops to a fraction of its summer peak.
The way each group rides within a week is different as well — members commute while casual riders explore more. Looking at a heatmap of when trips happen, one sees members light up Monday through Friday between 7 AM and 9 AM and again from 4 PM to 6 PM. Conversely, casual riders are seen most on Saturday and Sunday afternoons, with a long secondary smear into Friday evenings.
Additionally, what they’re riding has shifted out from under both of them. In early 2020, 16% of Divvy bike trips were on e-bikes. Today the share is closer to 70%. The crossover happened in mid-2022 for members and a few months later for casuals, and it has only accelerated since. The latest 12 months sit around 65% electric for members and 67% for casuals.
The trips themselves look different too: members’ rides cluster tight around a 9-minute median, while casuals take everything from quick cruises to 90-minute loops. But the more revealing cut is bike type crossed with rider type. A casual rider on an e-bike takes a median 10-minute trip — nearly identical to a member’s 9 minutes. Put that same casual on a classic bike, however, and the median jumps to 16 minutes, with a long tail stretching past an hour. E-bikes narrow the duration gap between the two groups, but the weekly and seasonal patterns stay distinct. Members still peak at weekday rush hour; casuals still own Saturday afternoons. The two groups ride at similar speeds now, but they still want different things from the network.
Which means the city’s infrastructure plan still needs to serve two jobs: efficient, separated routes from neighborhoods to the Loop for the weekday commuters, and safe lakefront and leisure access for the weekend crowd. E-bikes made the trips look more alike, but the infrastructure ask hasn’t converged. Lump the two groups together and you’ll build for an average rider who doesn’t exist.
Now, where do they ride? Map the routed Divvy bike volume onto Chicago’s actual street network and the answer is unambiguous. The brightest corridors are Clark, the Lakefront Trail, Broadway, Wells, and Lake Shore Drive. South of the Loop and west of Western Avenue, the network thins toward darkness. The system has stations on the South and West Sides, but the riding doesn’t follow.
That concentration is the part of the picture worth sitting with. Between 2020 and 2024, Chicago added more than 1,000 new Divvy stations outside the eight North Side and Near West neighborhoods that have always carried most of the system. Roughly 72% of new bike infrastructure miles also went to neighborhoods outside that core. Real investment, by any measure. What it produced: the core’s share of total Divvy bike trips went from 82% to 80%. Two percentage points after four years and 1,000 new stations. The map of where Chicago rides barely moved.
For context, even the core is undersized. Chicago logs about 2.2 Divvy bike trips per resident per year. DC’s Capital Bikeshare logs 8.9. The system has room to grow on every dimension that matters, and growth doesn’t follow a station map automatically.
What Chicago Built
Though the geographic patterns have remained broadly consistent, the investment in the infrastructure across Chicago has been undeniable. Between 2020 and 2026, the city added or upgraded more than 700 bike segments: protected lanes with concrete or plastic barriers, buffered lanes with painted margins, conventional painted lanes, neighborhood greenways with sharrows and traffic calming, and shared markings. Five types, covering nearly every approach a city can take.
Calling all of these “bike lanes” in the same sentence is a bit like calling a studio apartment and a four-bedroom house the same thing because they both have a front door. The differences matter, and they matter most when you start asking whether any of it worked. That question turns out to be three in disguise: did ridership grow, did crashes drop, and did the expansion reach the people the city said it would reach? Each one has a different answer.
Did it change how people ride?
To test whether each infrastructure type actually changed how much people rode, we compared every Divvy station to itself: how many trips did it see before the new infrastructure went in, and how many after? We controlled for everything else happening citywide in each month (weather, COVID recovery, e-bike adoption, the Bears playing well) so the only thing left to measure was the infrastructure’s own effect.
One type moved the needle:
Stations within four hundred meters of new protected bike lanes saw a nine percent increase in monthly Divvy bike trips after install, with a confidence interval from +2.8% to +15.5%. This means even on the conservative end of the estimate, it is still meaningfully above zero. For context, a similar analysis of New York’s Citi Bike system found an even larger +18% effect near new protected lanes, suggesting Chicago’s result is conservative but directionally consistent.
Buffered lanes, conventional painted lanes, neighborhood greenways, and shared markings all showed point estimates near zero, and none cleared statistical significance — meaning we can’t say with confidence that they moved ridership at all.
Did it impact rider safety?
9% more riders near protected lanes is real. But ask any cyclist what they actually want from a bike lane and the answer isn’t more company — it’s making it home safe. We ran the same type of analysis on crash data, comparing each corridor to itself before and after new infrastructure went in.
Neighborhood greenways — sharrows, speed humps, traffic calming on residential side streets — were the most consistent safety win in our data. Two-thirds of the 17 new greenway corridors saw per-cyclist crash rates fall after install. The median greenway’s rate dropped 41%. And when we applied the same causal method we used to measure ridership, this time on crash counts while controlling for everything else changing citywide, greenways showed a statistically significant 3.8% reduction in bicycle crashes.
Protected lanes, by contrast, show a murkier safety picture in our window. Only 10 of 24 protected corridors saw per-cyclist crash rates improve after install. The median protected corridor’s crash rate per rider actually ticked up 8%. Compare that to greenways, where two-thirds of corridors improved and the median dropped 41%. Read those numbers at face value and you’d conclude that the infrastructure proven to grow ridership doesn’t improve safety. You’d be wrong, but it takes a minute to see why.
Remember from the previous section that protected lanes grew ridership by 9%. That growth isn’t random. The new riders showing up are disproportionately the cautious ones who wouldn’t bike next to traffic but will bike behind a barrier, the group researchers call “interested but concerned” (Dill & McNeil, 2016). So after a protected lane goes in, the number of cyclists on the corridor jumps — and more riders means more total crash exposure. Crash counts rose, and the per-rider rate ticked upward with them — not because the street got more dangerous, but because the lane’s safety reputation put more people on it. Researchers call this the exposure paradox, and it’s a real problem for any city trying to grade its own bike-lane scorecard.
Longer studies with larger samples consistently resolve the paradox in favor of protection. A landmark Canadian study found 89% lower injury odds on cycle tracks compared to major streets (Teschke et al., 2012), and FHWA’s 2023 analysis of separated lanes across U.S. cities confirmed the pattern. Our twelve-month window is simply too short, and the ridership growth too strong, for the safety signal to outrun the new riders.
The takeaway: the safety wins our data captures most cleanly come from the cheapest infrastructure Chicago deploys. Sharrows, speed humps, paint and traffic calming on residential side streets.
Where Chicago should build next?
So protected lanes drive ridership and greenways drive safety. That’s what the data says about the last 100 miles built. The harder question is where to spend the next 100. We took everything we learned and built a priority index that scores 4,473 street corridors across Chicago on four dimensions:
- Safety need: bicycle crash density on the corridor, with serious injuries (hospitalizations and worse) counted double. More crashes and worse outcomes mean a higher safety score.
- Demand: observed Divvy trip volume at nearby stations (60%) blended with surrounding population density from Census data (40%). The population component ensures corridors with real residential density but few Divvy stations — mostly on the South and West Sides — don’t score zero just because the bike share hasn’t arrived yet.
- Network gap: would upgrading this corridor connect existing safe routes into a larger network? We classified every Chicago street by its Level of Traffic Stress (Mekuria, Furth & Nixon, 2012), mapped the existing low-stress cycling network, then simulated each candidate corridor as a new link and measured how many new station-to-station connections it would create. Corridors are scored sequentially: once the top-ranked corridor is “built,” the next one is evaluated against the updated network, so the index doesn’t stack redundant routes in the same area.
- Equity: share of low-income households in the surrounding community area, scored using the z-score methodology from the League of American Bicyclists’ Bicycle Equity Index (Prelog, 2015). Only neighborhoods meaningfully above the citywide average in economic need receive equity points — preventing the index from rewarding areas that are already well-resourced.
The weighting: Safety 30%, Demand 25%, Network gap 25%, Equity 20%. These weights are our analytical judgment — there is no universal formula — but the multi-factor structure follows corridor prioritization frameworks used in city bicycle plans nationally, including Seattle’s Bicycle Master Plan (2014). A corridor that scores high has to check multiple boxes: it needs to be dangerous, well-traveled, structurally important to the network, and in a community that could use the investment.
Milwaukee Avenue tops the list — here’s why the math checks out on all four dimensions.
Safety: 218 bicycle crashes on its corridor footprint since 2020, more than any other unprotected corridor in the city.
Demand: nearly a million Divvy bike trips at adjacent stations. Milwaukee is already one of the most-ridden cycling corridors in Chicago, which means the infrastructure wouldn’t be speculative: riders are already there, mixing with car traffic every day.
Network gap: this is where Milwaukee separates from the rest of the list. Right now, Chicago’s low-stress cycling network (the streets where you can ride without merging into fast-moving car traffic) is split into two large disconnected pieces. Upgrading roughly a mile and a half of conventional lane on Milwaukee to protected status would bridge them, joining more than 4,400 intersections into a single connected network. A cyclist on the north end could, for the first time, reach the south end without leaving the protected grid.
Equity: West Town and the surrounding neighborhoods score meaningfully on the income dimension, and Milwaukee serves as a primary commute corridor for residents across a range of income levels.
Chicago has been arguing about protecting Milwaukee Avenue for 15 years. The city finally started in 2025 — the data says finish the job.
The verdict
So did 100 miles of bike lanes change anything? In Pilsen, on Wrightwood, on the corridors where stations and demand and infrastructure converged: yes. Stations near new protected lanes are nine percent busier than they would have been. Two-thirds of new neighborhood greenways are measurably safer per cyclist, and on the strongest corridor in our data crashes fell 42%. That is real, and it is not random.
But many of us have the habit of grading projects on what got built rather than what changed — and not just at CDOT. It’s the easier thing to count, and counting it feels like accountability. CDOT publishes total crash counts and centerline miles installed. Neither metric captures what the data actually shows: that safer infrastructure attracts more riders, that the cheapest treatment delivers the most consistent safety gains, and that the expansion outside the core reached neighborhoods where the cycling ecosystem doesn’t yet exist to support it.
The data has been telling Chicago what to do. The next 100 miles are a chance to listen.
Thanks for reading! If you’d like more information about our methodology and sources, or if you’re interested in how we can apply analyses like these to your business, shoot us a note at info@southshore.llc or drop a comment below.
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