Experts on Camera

Dr. Kari Watkins: What’s next for public transit?

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For many public transit systems, ridership is much lower today than pre-pandemic levels.

On Tuesday, October 11, 2022, SciLine interviewed: Dr. Kari Watkins, an associate professor of civil and environmental engineering at the University of California, Davis. She discussed topics including: public transit ridership trends, and why they matter to communities; why some transit agencies are facing a “fiscal cliff” when pandemic-related aid expires; how cities are trying to increase ridership amid the widespread shift away from in-office work–and what seems to be working; how public transit affects climate change, public health, and traffic congestion; and her research on ways to make transportation more equitable and environmentally friendly.

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KARI WATKINS: My name is Dr. Kari Watkins. I’m an associate professor in civil and environmental engineering at the University of California at Davis, and I study ways to make our transportation system easier to use, more sustainable, healthier and more efficient.


Interview with SciLine

Why is transit a sustainable mode of transportation?


KARI WATKINS: Economically, it’s easier on people’s pocketbooks. It’s easier to afford taking transit. Environmentally, transit has less emissions per trip. And so, it’s going to be more sustainable in that way. And in equity—from an equity point of view, transit is more sustainable than other modes because you’re more able to serve all people. This service is out there—you don’t have to afford a vehicle in order to be able to take it.

But part of my job is to make sure that transit is as sustainable as it can be. And this means from an environmental perspective that we’re looking at alternative fuels, that we’re trying to fill the vehicles as much as possible, that we’re encouraging more people to ride. These are going to help transit be more environmentally sustainable. Economically sustainable—we need to do things to make sure that transit is going to be around into the future, that we’re funding it in ways that we know these services are going to be available, that people are going to have something they can rely on for transportation because we’re providing good transit services. And then from an equity perspective, we need to make sure that we’re providing transit services that are not favoring certain kinds of riders, that all people who are trying to use transit are getting the best possible trip that we can give them.

How does transit help our transportation system be more environmentally friendly?


KARI WATKINS: The great thing about transit is that it gets our steps in. We—in accessing transit, we’re often more active than we would be if we’re driving from place to place. And transit is also a big part of being multimodal. So, it encourages us to use walk trips and bike trips as part of our overall program. Whereas if we’re just driving everywhere and that’s sort of the default mode and the habit that we have, then we’re going to use less of all of these other modes and be less healthy people because that automobile trip is the one that is always taking the greatest toll on our health in terms of not getting physical activity in.

What has research shown us about transit’s safety?


KARI WATKINS: Transit is the safest mode of transportation because of the professional drivers, because of the nature of how the services are provided, because they’re often in their own corridors with really, really high factors of safety in how those corridors are designed. Transit is the safest way that we can get around, and we see this play out in different statistics. When we look at cities where more people take transit as opposed to driving themselves, we always have lower crash rates, both internationally and across the U.S.

How does public transit affect traffic congestion?


KARI WATKINS: There’s been studies done by agency—well, organizations such as the Texas Transportation Institute, where they look at what the impacts of congestion are in different ways. And just in our largest few cities, we’re saving about 15% of our congestion levels by having transit in those cities. And the relationship between traffic flow and the available space to be using is such that it’s not linear. And so, 15% makes a very big difference in the amount of congestion that we would see in those cities if those transit systems didn’t exist. And so, as we try to make more efficient transportation systems, try to get us out of congestion and give us more choices, transit is a big part of that. Cycling or using other smaller vehicles is a big part of that as well.

What are some trends of ridership on public transit systems in recent years?


KARI WATKINS: Over the past approximately five years, just before COVID, we were seeing declines in both bus and rail in ways that we had not seen before and could not be attributed to things like population decreases or lower employment rates or things like that. So, we collected a whole bunch of data in order to try to understand this better. And there are reports that can be shared through the national—well, it’s actually the Transit Cooperative Research Program. It’s an arm of the Transportation Research Board. And these reports are freely available so anybody can look at their particular transit agency and see what the trends were and look at the results of what we were seeing. But we saw declines that could be largely attributed to the rideshare companies. So, Uber, Lyft were taking a pretty heavy toll on transit ridership. In addition to this, gas prices were hitting it. When our gas prices go down, transit ridership is going to go down. And a little bit of increases in fares on transit systems was also hitting transit ridership. In addition to that, although population and employment were up, density was not. We—our cities were already becoming less dense.

And so, between all of those things, we were seeing some pretty major declines in transit ridership. And then COVID hit. So, those declines got even bigger, especially on the rail side. What happened during COVID was a lot of the people who rely on transit on a day-to-day basis, those critical workers, folks who were keeping our society going during the early parts of COVID—they still had to get to work. And many of those folks are bus riders as opposed to rail riders, because of the way we’ve set up these systems. And so, we saw bus ridership decline, but it was still at significant portions of what it was before COVID. So, even at the worst points, most bus systems were still at 50% of the ridership that they had pre-COVID. Rail, on the other hand, was decimated, especially commuter rail. Most commuter rail agencies are even still today nowhere close to what they were pre-COVID. And in sort of the early days of everything, they were at 10% of the ridership levels that they once were. We’re seeing some agencies where they’re predicting that in the next year or two, they’re going to be back up to the levels that they were pre-COVID. But there’s a lot of agencies that have been permanently hit.

Why are some transit agencies facing a “fiscal cliff?”


KARI WATKINS: What happened during COVID was that many of these agencies were rescued through government programs where they got extra operating funds because the federal government and state governments knew that these agencies were going to be facing such dramatic declines in ridership that they wouldn’t be able to provide their services without some sort of extra support. But all of that extra operating funding is disappearing over time. And with some agencies, they expect it’ll last another year, maybe two, but they’re not sure if their ridership is projected to be back at the same levels that it once was.

Can you discuss your research on ways to make public transit more equitable?


KARI WATKINS: Some of the more recent research that we’ve done on equity has been around how routes are planned. Oftentimes, pre-COVID, we were chasing after what we called the choice riders. So, we were very, very worried about attracting more people to transit, which is a great thing because it can help make our cities more sustainable. It can help people lead healthier lifestyles by choosing transit. So, it’s great to go after these people who have a choice, who can afford a vehicle and maybe would be driving, but we’re all going to benefit by them choosing transit instead. But in the process, we often forget about the people who need transit, who are relying on it on a day-to-day basis. They can’t afford a vehicle, or they can, but making the choice to own a vehicle would substantially hurt their financial outlook. And so, they’re choosing a cheaper mode of transportation and taking transit. And in the process of doing so, they’re treated like a second-class citizen.

So, a lot of the work that we’re doing is looking at how do we actually assess routes based on who is taking them and assess service plans and future transit provision like the routes that we’re putting out there, how we’re going to provide service to people, how do we come up with metrics to understand who is being served? Are we actually serving people in ways that those who need transit the most are the ones who are getting the most service and the most options?

How could transit become more environmentally friendly?


KARI WATKINS: There’s actually a lot that can be done to our system if we electrify transit further. For decades, we’ve had transit lines that had overhead systems where it would power it and things like that. But those are expensive to build. Or a third rail system—so, where it’s powered from underneath, like our subway systems and such. All of those are really expensive to build. But battery technology that is coming around for our cars, for our passenger vehicles, is also coming around and improving greatly for larger-scale vehicles, so trucks and buses and such. And so, this gives us the ability to start to electrify routes that are running in—on pavement in general streets. And the hang-up there is simply that we have to have the ability to run these routes often for an entire day. And the window to charge them is just a small window overnight.