If we want to increase escalator capacity, why don’t we just run the things faster?

A busy day on the tube. Image: Getty.

While Londoners may still be recovering from the trauma, many outside the capital probably completely missed Transport for London’s audacious and sacrilegious experiment at Holborn station.

For three weeks, tube passengers stood on both sides of the escalators going up from the platforms to the ticket hall. There were people standing on both the left and the right. Nobody could walk.

I know: it was madness. I understand your anguish.

TfL’s logic was as follows. On long escalators, the vast majority of people won’t want to walk because humanity is an intuitively lazy species. Thus, huge queues build up at the bottom of the escalator as large volumes of people try to squeeze onto the right-hand side, so that they can obediently stand in line as they chug slowly upwards, like a slightly less sedate, slightly less terracotta terracotta army.

The experiment largely failed, because basically people are stubborn and changing the behaviour of large groups is, like, really hard. But anyone who has stood in a soul-crushing human mob at the bottom of an escalator at a tube station in rush hour will understand just how pressing the need is for a way to increase escalator capacity.


There’s an obvious solution – one that’s likely been suggested by amateur masters of logistics all over the world every time they’ve found themselves in such mildly antagonising and incremental-delay-incurring situations: run the things faster.

Theoretically, of course, this is possible. Escalator speeds vary a great deal anyway, even within London – those in shopping centres or department stores tend to run at about 0.5 metres per second, whilst the London Underground standard is 0.75 metres per second.

Looking further afield, city transport networks across the world run their escalators at all sorts of different speeds. New York City’s are horrendously slow, running at about 0.45 metres per second, whilst Prague, Stockholm, Beijing, Shanghai, and Guangzhou settle around the stately 0.6 metres per second mark. Sydney, Singapore, and Seoul’s systems square up sensibly to London’s standard speed in the 0.75 metres per second region, with Seoul pushing ahead slightly at 0.78 metres per second. The trailblazer, though, is Hong Kong, whose escalators breeze along at 0.8 metres per second.

Fantastic! Great! So, all we have to do is compare escalator capacity in Hong Kong MTR stations with capacity in London tube stations, and-

This escalator on the Stockholm metro is not suffering from overcrowding. Image: Getty.

Unfortunately the comparison isn’t that simple. London’s escalator steps are, as standard, 1 metre wide and 0.4 metres deep. Many of Hong Kong’s escalators are significantly narrower and not as deep. Whether that’s clever space-saving on Hong Kong’s part, or ingenious future-proofing for the post-mass-obesity world by Transport for London, we may never know – but either way, it changes the rate at which steps reach the top, rendering direct comparisons based on speed alone impossible.

The speed limit

What we can do instead is to look at a bizarre study carried out by four students from Hong Kong on the relationship between escalator speed in metro systems and “pace of life”. They described that rather dubious metric described as “the rate; speed and relative rapidity or density of experiences, meanings, perceptions, and activities”. They calculated it by combining economic, climate, employment, and population indices.

One of the things they did as part of that study is to conduct reasonably lengthy interviews with users of metro systems (principally the Hong Kong MTR) about their experiences of the escalators on that system, and how that related to their impression of the city’s “pace of life”.  One businesswoman in her mid-twenties interviews for the study said that “Hong Kong people are used to the fast”; but most of the non-locals that they spoke to, mostly from mainland China, said that the escalators on the Hong Kong MTR were “too fast”.

Such comments highlight one of the biggest problems with running escalators faster. A study by Paul Davis and Goutam Dutta has already shown that the presence of non-commuters decreases capacity on London’s escalators. Meanwhile, an experiment with variable speed escalators in New York ended up with a Indian visitor falling over.

There is quite obviously a safety danger to be taken into account if you’re going to start running escalators at 0.8 metres per second or faster. The queues at the bottom of Holborn’s escalators might be shorter most of the time if said escalators are whizzing passengers upwards at silly speeds – but they’ll likely be considerably longer while the paramedics try and reach the elderly man who’s tumbled fifteen metres down an up escalator. Swings and roundabouts, you know?

For those less interested in actual human health and welfare, and more interested in the technical side of running large transport networks, there’s another problem with running such escalators at speed. The average walking speed is around 1.3 metres per second. If you take the running speed of London Underground escalators – 0.75 metres per second – and the rate at which people generally ascend the steps if they’re walking – around 0.7 metres per second – you end with a speed of 1.45 metres per second.

So people walking up escalators are actually travelling slightly faster than they do the rest of the time. And that’s a problem. When it’s only an incremental difference (0.15 metres per second), it leads to nothing more dangerous that awkward mincy super-walk that people do for the first few seconds after walking off the end of an escalator.

But when there’s a bigger difference in speed, it can cause major problems. Either, people trip over their own feet trying how to remember how to walk on non-moving ground, and cause a capacity-reducing pile-up in the process; or people stop at the top of the escalator to prepare themselves for walking on non-moving ground. And cause a capacity-reducing pile-up in the process.

Neither does this one in Lisbon. Pretty, though. Image: Getty.

Essentially, speeding up escalators causes more problems than it solves, and is ultimately no more than the silly solution of the kind of person who still hasn’t grown out of the childish habit of following every piece of information with, “But why?”

Start again

Fortunately, researchers Davis and Dutta do come up with some more sensible alternatives. Unfortunately, these are the sort of drastic changes that are much easier to implement you haven’t built your metro system yet than they are if you’re trying to unclog a jam-packed 150-year old system.

Of the many London Underground escalators they studied, the researchers found that those with the highest peak-time capacity were escalators with open, orderly approaches, not impeded by awkward corners and cross-flow confusions.

They found that having a corridor between the platform and the escalators acts as a filter for passengers alighting a train, improving capacity as passengers naturally filter out into two lines – one for walking and one for standing – in an orderly way (rather than the human crush you get when you come straight off the platform, turn a corner, and suddenly there’s an escalator). Interestingly, single escalators have a higher capacity than double escalators, because passengers don’t dither trying to work out which escalator to take.

So. If you want to get more of your passengers onto your struggling escalators during peak hours, you basically need to redesign your entire underground station. You need to build stations that naturally filter your passengers out into fast walkers, slow walkers, escalator standers and escalator walkers, and divide them into distinct groups.

Most of all, you need to not break any codes of etiquette that are probably as old as the city itself.

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Urgently needed: Timely, more detailed standardized data on US evictions

Graffiti asking for rent forgiveness is seen on a wall on La Brea Ave amid the Covid-19 pandemic in Los Angeles, California. (Valerie Macon/AFP via Getty Images)

Last week the Eviction Lab, a team of eviction and housing policy researchers at Princeton University, released a new dashboard that provides timely, city-level US eviction data for use in monitoring eviction spikes and other trends as Covid restrictions ease. 

In 2018, Eviction Lab released the first national database of evictions in the US. The nationwide data are granular, going down to the level of a few city blocks in some places, but lagged by several years, so their use is more geared toward understanding the scope of the problem across the US, rather than making timely decisions to help city residents now. 

Eviction Lab’s new Eviction Tracking System, however, provides weekly updates on evictions by city and compares them to baseline data from past years. The researchers hope that the timeliness of this new data will allow for quicker action in the event that the US begins to see a wave of evictions once Covid eviction moratoriums are phased out.

But, due to a lack of standardization in eviction filings across the US, the Eviction Tracking System is currently available for only 11 cities, leaving many more places facing a high risk of eviction spikes out of the loop.

Each city included in the Eviction Tracking System shows rolling weekly and monthly eviction filing counts. A percent change is calculated by comparing current eviction filings to baseline eviction filings for a quick look at whether a city might be experiencing an uptick.

Timely US eviction data for a handful of cities is now available from the Eviction Lab. (Courtesy Eviction Lab)

The tracking system also provides a more detailed report on each city’s Covid eviction moratorium efforts and more granular geographic and demographic information on the city’s evictions.

Click to the above image to see a city-level eviction map, in this case for Pittsburgh. (Courtesy Eviction Lab)

As part of their Covid Resource, the Eviction Lab together with Columbia Law School professor Emily Benfer also compiled a scorecard for each US state that ranks Covid-related tenant protection measures. A total of 15 of the 50 US states plus Washington DC received a score of zero because those states provided little if any protections.

CityMetric talked with Peter Hepburn, an assistant professor at Rutgers who just finished a two-year postdoc at the Eviction Lab, and Jeff Reichman, principal at the data science research firm January Advisors, about the struggles involved in collecting and analysing eviction data across the US.

Perhaps the most notable hurdle both researchers addressed is that there’s no standardized reporting of evictions across jurisdictions. Most evictions are reported to county-level governments, however what “reporting” means differs among and even within each county. 

In Texas, evictions go through the Justice of the Peace Courts. In Virginia they’re processed by General District Courts. Judges in Milwaukee are sealing more eviction case documents that come through their courtroom. In Austin, Pittsburgh and Richmond, eviction addresses aren’t available online but ZIP codes are. In Denver you have to pay about $7 to access a single eviction filing. In Alabama*, it’s $10 per eviction filing. 

Once the filings are acquired, the next barrier is normalizing them. While some jurisdictions share reporting systems, many have different fields and formats. Some are digital, but many are images of text or handwritten documents that require optical character recognition programs and natural language processors in order to translate them into data. That, or the filings would have to be processed by hand. 

“There's not enough interns in the world to do that work,” says Hepburn.


Aggregating data from all of these sources and normalizing them requires knowledge of the nuances in each jurisdiction. “It would be nice if, for every region, we were looking for the exact same things,” says Reichman. “Instead, depending on the vendor that they use, and depending on how the data is made available, it's a puzzle for each one.”

In December of 2019, US Senators Michael Bennet of Colorado and Rob Portman of Ohio introduced a bill that would set up state and local grants aimed at reducing low-income evictions. Included in the bill is a measure to enhance data collection. Hepburn is hopeful that the bill could one day mean an easier job for those trying to analyse eviction data.

That said, Hepburn and Reichman caution against the public release of granular eviction data. 

“In a lot of cases, what this gets used for is for tenant screening services,” says Hepburn. “There are companies that go and collect these data and make them available to landlords to try to check and see if their potential tenants have been previously evicted, or even just filed against for eviction, without any sort of judgement.”

According to research by Eviction Lab principal Matthew Desmond and Tracey Shollenberger, who is now vice president of science at Harvard’s Center for Policing Equity, residents who have been evicted or even just filed against for eviction often have a much harder time finding equal-quality housing in the future. That coupled with evidence that evictions affect minority populations at disproportionate rates can lead to widening racial and economic gaps in neighborhoods.

While opening up raw data on evictions to the public would not be the best option, making timely, granular data available to researchers and government officials can improve the system’s ability to respond to potential eviction crises.

Data on current and historical evictions can help city officials spot trends in who is getting evicted and who is doing the evicting. It can help inform new housing policy and reform old housing policies that may put more vulnerable citizens at undue risk.

Hepburn says that the Eviction Lab is currently working, in part with the ACLU, on research that shows the extent to which Black renters are disproportionately affected by the eviction crisis.

More broadly, says Hepburn, better data can help provide some oversight for a system which is largely unregulated.

“It's the Wild West, right? There's no right to representation. Defendants have no right to counsel. They're on their own here,” says Hepburn. “I mean, this is people losing their homes, and they're being processed in bulk very quickly by the system that has very little oversight, and that we know very little about.”

A 2018 report by the Philadelphia Mayor’s Taskforce on Eviction Prevention and Response found that of Philadelphia’s 22,500 eviction cases in 2016, tenants had legal representation in only 9% of them.

Included in Hepburn’s eviction data wishlist is an additional ask, something that is rarely included in any of the filings that the Eviction Lab and January Advisors have been poring over for years. He wants to know the relationship between money owed and monthly rent.

“At the individual level, if you were found to owe $1,500, was that on an apartment that's $1,500 a month? Or was it an apartment that's $500 a month? Because that makes a big difference in the story you're telling about the nature of the crisis, right? If you're letting somebody get three months behind that's different than evicting them immediately once they fall behind,” Hepburn says.

Now that the Eviction Tracking System has been out for a week, Hepburn says one of the next steps is to start reaching out to state and local governments to see if they can garner interest in the project. While he’s not ready to name any names just yet, he says that they’re already involved in talks with some interested parties.

*Correction: This story initially misidentified a jurisdiction that charges $10 to access an eviction filing. It is the state of Alabama, not the city of Atlanta. Also, at the time of publication, Peter Hepburn was an assistant professor at Rutgers, not an associate professor.

Alexandra Kanik is a data reporter at CityMetric.