Link to the study exactly. https://advances.sciencemag.org/content/5/5/eaau2670 Having just read the study the results make sense. The authors look at car ownership reduction. They find that Uber and Lyft are not actually helping with that. We do not observe a meaningful change in car ownership, with an average of 1.08 cars per household in 2010 and 1.10 cars per household in 2016 (36).

This is because as people move towards dense urban centers they are now sometimes electing to use Uber and Lyft instead of transit. The thing is because parking and driving is so expensive as is living in a dense prolific city, you probably wouldn't have wanted a car anyway.

The findings clearly show Uber and Lyft create traffic. The speed data used in this study confirm this trend, showing that the average speed decreases from 25.6 miles per hour (mph) in 2010 to 22.2 mph in 2016 and that the vehicle hours of delay (VHD) increase by 63% over the same period.

In addition to the 20% of TNC VMT that is out-of-service, 70% of San Francisco TNC drivers live outside the city

It makes sense that Uber and Lyft actually worsen traffic. They bring cars and congestion into the city and create public transit competitors.

I have the one for NYC here also http://www.schallerconsult.com/rideservices/unsustainable.pd...

The question is what is the best response to help the environment? It seems that supporting Uber and Lyft is contrary to sustainable objectives. Is that partially why many cities and countries do not want them to operate in their jurisdiction?

    1.  Crime
    2.  Forces you to come in contact with people you would not choose to associate with normally
    3.  Public transportation vehicles are often dirty/unclean
    4.  Long waits during off peak times, often, which forces you to revolve your schedule around public transportation
    5.  Commutes are often longer
    6.  Can't get to your destination often without a long walk, or another vehicle
    7.  Usually still requires walking in the rain/hail/snow/sleet/wind/sub-zero temps
    8.  Initial build out and future expansion are very expensive.

> The new findings, based on a computer model that simulated the speed of traffic with Uber and Lyft vehicles removed

Not sure if that's actually what's going on, but if it is, it's a ridiculous conclusion. Let me rephrase: "Japanese cars are making traffic in the USA worse, based on a computer model that simulated the speed of traffic with Japanese vehicles removed."

It's not just the number of cars causing issues; the number of roads with ad hoc lane closures due to ride sharing pick-ups and dropoffs makes a huge difference. Many three lane streets get choked down to one lane if a delivery truck blocks a right lane and a ride share blocks the left. It's very visible every rush hour in SF.

Anything that makes it more convenient for people to get from A to B in a _car_ will, of course, create more traffic. Convenience increases usage.

Uber/Lyft may make it unnecessary for some folks to own a car, but a reduction in car ownership does not mean a reduction in car usage.

Obviously. They are making it worse by exactly the number of trips that would otherwise have been done by transit, bike, walking or not at all.

edit: or now scooters

Yes, there are cars that are performing transport and some that are part of traffic that are waiting to be hailed and not performing transport - those are certainty congesting. There is also the effect of rideshare drivers coming from different areas and thus not knowing the city they are in. Reliance on GPS/map apps helps but there will still be “I don’t know where I am going and am not accustomed to city traffic” effect that compounds the others drivers who exhibit that behavior. I’m sue we’ve seen the effect of a single driver desperately trying to cross lanes to make their turn, scale that up.

Cities should really get this data from the companies to figure this out. That should be a necessity for operation in the city.

I found it ironic that Lyft/Uber has been a godsend to the Phoenix area. Cabs were always horrible / impractical here.

When I'm in SF and other major cities, I tend to lean towards cabs more.

Anytime there is no passenger in the vehicle, it's an extra vehicle on the road. Normally, our cars don't continue to drive around after we've arrived at our destination.

Good to see this. Earlier assumptions that rideshare would reduce traffic ignored how the transport system would change. Also similar to the way Airbnb can make housing more expensive or unavailable.

I live in San Francisco. Public transport is a joke. Buses are so dangerous that I won't take them (took them twice when I moved here and almost got beaten up the first time, witnessed someone getting mugged the second time (near tartine)).

I went from exclusively using public transport (previously living in UK/France) to exclusively taking uber/lyft. Thanks humanity my work provides shuttle to do the commute to south bay, I would never be able to do that with the caltrain. Mad respect to those who have to do it.

You can probably tell I'm salty about the state of things here. As a matter of fact I just passed my driving writting exam today because for the first time of my life I feel like I need a car.

I remember when Uber was “supposed” to be a ride sharing service where you could make extra money along your intended destination. It wasn’t touted as a taxi service.

Presumably this is the standard problem with Uber/Lyft:

Uber/Lyft make the vast majority of their income in areas that are already well-served by taxis. Consequently, they make the problem worse.

Presumably, in the cities not well-served by taxis, they improve the situation. However, they don't generate anywhere near the income.

NYC area driver here... TLDR the entire article but I'll give my first hand perspective to say that "T" (taxi) and "L" (livery) plated vehicles on the highways in the NY metro area DO significantly add to congestion as the drivers keep their speeds well under the limit while traveling in passing lanes. Frequently I see these non "cab" "T" and "L" vehicles that I assume are "transportation network" company contractors driving unusually slow because they're either on their mobile devices (looking for pickups?) or driving so under the limit that I assume to not break any GPS speed monitoring rules enforced by these "transportation network" companies, or just generally inept.

I'm not advocating speeding by any means, but after driving 500k+ miles in the NYC metro area you can spot the ineptness and/or driving under fear of speed monitoring of these "T"/"L" plated vehicles. All it takes is for one to be driving 45 mph in a 55 zone on a two lane road with an already congested merge ahead, or they travel in the left passing lane at speeds well under the limit preventing other motorists from advancing, or overall poor driving, then it's a chain reaction of braking and delays mounting behind them.

I've always assumed that the monitoring of these drivers adherence to speed limits is the reason why they travel noticeably slower than the average driver in normal traffic. If that's the case it unfortunately causes the average capable driver to become indirectly part of the "transportation network"'s speed monitoring resulting in delays for everybody.

In the relative absence of these "T" and "L" plated vehicles, I've driven in moderate to heavy volumes where the average speeds are in the 60-65+ MPH range. However, when the livery vehicles start to increase within similar volumes of traffic the average speeds seem to drop and the congestion related delays seem to increase.

So if you were to ask me "Do transportation network companies decrease or increase congestion?" My answer would be "yes". Why? Based on my observations, I suspect it's related to the speed monitoring of the "transportation network" company and a tendency of the drivers of these vehicles being inept relative to other non "transportation network" drivers.

The Uber/Lyft driver strike a couple days ago was a good demonstration of this; my drive to work was significantly easier that day, as was the drive home, with noticeably fewer cars on the road.

Why can't they just teach drivers to leave a bunch of space in front of them and help improve the traffic? Use the app to reinforce it...

They certainly make Manhattan traffic worse.

On the flip side, car owners make traffic worse for Lyft and Uber users.

I'd rather we penalize normal car owners than penalize Lyft and Uber. I use Uber Pool every day to get to my bus stop, and there's no good alternative.

Alternative: More Parking

Url changed from https://www.sciencemag.org/news/2019/05/uber-and-lyft-may-be..., which points to this.

> Uber and Lyft have long said their services may relieve urban congestion by facilitating access to public transit

This was always questionable for a place like SF or any high density city.

Few people take a ride share to get to a bus or a MUNI light rail stop in SF. If you are paying for the Uber/Lyft, why would you pay again for a bus ticket, especially given the inconvenience of then waiting for the bus. You'll just stay in the car to your destination, after all San Francisco isn't that big.

The exception is perhaps people in SF getting to BART to go to a suburb, but that's not a very significant use case.

Edit: removed potty language, and superlatives.

I don't think it is so simple. Eg: people now taking extra trips because it is easy and cheap to do so. Eg: "I'll just Uber the 6 blocks to my next shopping spot" instead of walking. This happens in my friend group all the time. Plus people traveling to the city at all BECAUSE Uber makes intracity travel easy. Eg: I live in the East Bay and hate driving within the city, but am happy to be escorted around it on a whim but would have otherwise stayed more local.

Funny you say that because most of my Uber/Lyfts consist of me going to and from public transit for my intended destination.

Although it is more complicated than that, as I often take a shared ride home because Bart shuts down too early on weekends to be useful on the way back.

Additionally the math gets complicated when I have multiple people with me, as often times it's cheaper to uber/lyft somewhere to our destination than it is for all of us to individually pay for a Bart ticket.

Actually, you take that number, PLUS the number of empty Uber cars, PLUS the number of empty taxis that would not have been empty if there wasn't Uber...

So, we consider people being able to do something in a way they would much rather do it as a negative? If you have the choice between walking and an Uber, and you really want to walk, then just walk. If you have the choice between walking and walking, but you really don't want to walk, then you're worse off.

Clearly a trip that is taken has utility to the person taking the trip, so the "not at all" outcome is a bad one.

People will use the best option they have out of the ones available to them. Transit is usually faster than Uber for trips to downtown or the Mission, but try getting to Miraloma with it.

And, following this, these different effects probably have different values for society, i. e.:

- Replacing public transit = unmitigated bad

- Replacing walking, bike = even worse, bikes are unbeatable for health, space efficiency, energy use, noise, and really any other category

- Replacing using own car = close to neutral, maybe slightly positive, especially when it allows people on the margin forgo car ownership entirely

- Non-consumption = likely positive, taking a trip you otherwise wouldn't take is a sign of increased freedom/participation in society and would tend to outweigh environmental concerns in my subjective judgement

There's also a larger impact for cars that block traffic by stopping in the lane in front of a pickup or drop address where there isn't room to pull over.

And there's an impact from out-of-town weekend drivers that don't know where they're going and take a dumb route because of that unfamiliarity.

Also every driver I meet in SF has driven from somewhere else to "work" in the city.