Access-oriented design? Disentangling the effect of land use and transport network on accessibility

Recently published:

  • Lahoorpoor, B., Rayaprolu, H., Wu, H., and Levinson, D. (2022) Access-oriented design? Disentangling the effect of land use and transport network on accessibility. Transportation Research Interdisciplinary Perspectives [doi] [Open Access]

In urban planning and design, a holistic perspective is needed to examine multiple potential scenarios in future developing plans. Access (or accessibility) is a concept that measures the performance of a city in terms of how easily residents can reach their desired activities. The land use pattern and the transport network configuration are the two critical elements of spatial access measures. This study investigates whether access-oriented design can improve accessibility outcomes, and disentangles access benefits from network design and land use patterns. A generic superblock with two types of street network design is defined, and populated with two different land use allocation strategies. Local access is measured from transit stops. Furthermore, to test the hypothesis at a larger scale, the Liverpool LGA in Sydney is selected, and different combinations of land use pattern and network topology are tested. Results indicate that the land use pattern plays a vital role in the local access; however, the network configuration significantly impacts the access at the regional scale. The application of access-oriented designs in future urban growth is discussed.

Two different superblock layouts: Grid vs. Ring-Radial.

 Five Quick Questions for . . . transportation expert David Levinson

I did a 5QQ for my friend James Pethokoukis’s optimistic, pro-technology, pro-growth newsletter Faster, Please, to which you should subscribe or follow via RSS.

5QQ

❓ Five Quick Questions for . . . transportation expert David Levinson

David Levinson teaches at the School of Civil Engineering at the University of Sydney, he’s an honorary affiliate of the Institute of Transport and Logistics Studies, and he serves as an adjunct faculty at the University of Minnesota. He’s also the co-author The End of Traffic and the Future of AccessIn addition, he authors the Transportist blog.

1/ America seems to be suffering a car crash epidemic. Why and what can we do about it?

There are many causes to this problem, which is another example of American exceptionalism, as crashes are declining in most developed countries (see figure, via David Zipper). Crashes result from high speed (wide lanes American lanes encourage fast driving, and high powered cars make it possible [to] drive faster than any posted speed limit — how high does your speedometer go?) mixed with slow reaction time (e.g. distracted and inebriated drivers, plus diminished ability to see what’s in front of them, higher speeds for instance focus drivers on distances far ahead rather than seeing what’s in their peripheral vision, or just in front of them). Fatalities are crashes where the speed (which has been increasing) and mass (which has also been increasing) are both too high. Two pedestrians colliding at walking speeds will not kill anyone. A car hitting a pedestrian at 40 mph will likely kill her. In fact, most cars are now trucks, significantly higher and heavier than cars of a few decades ago. I wrote about this a couple of years ago: 21 Solutions to Road Deaths

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2/ When will we have a million self-driving cars on the road, ones that can at least be autonomous on highways?

It depends on what you mean by “autonomous”. In some ways we already have a million autonomous cars. Elon Musk will tell you his cars Autopilot systems are “Full Self-Driving” on highways now, and have been in beta mode for FSD on city streets for a number of years. General Motors will sell you “Super Cruise” in a number of Cadillac models, which allows hands off driving on 200,000 miles of highways. GM’s Ultra Cruise is supposed to launch hands off driving on 2 million miles of public roads (highways and streets) in 2023. In all of these cases, the driver is supposed to monitor the vehicle, so if by autonomous you mean the driver can safely go to sleep, we are not there yet, and are looking to late this decade. 

3/ Will hyperloops ever be a real-world mode of transportation?

We can’t build subways or high-speed rail lines at reasonable cost in the US, and we are supposed to try to build an unproven technology? Hyperloop is a moving target, but if we mean maglev with small carriages in evacuated tubes, I don’t think so. The maglev is slowly getting deployed in places, Shanghai has had a small line operating for years, which I rode. Japan has a major line under construction now (to open 2027). But making them go even faster by putting them in tubes with the air removed (to reduce air resistance and increase speed) is untested and brings new engineering challenges. Using small carriages, with sharp acceleration and deceleration, as originally proposed, and spacing them close together, brings new risks.

4/ Will air taxis ever be a common mode of transportation?

Yes, but not this year. Since the 1920s people have dreamt of an autogyro in every garage. It was a key mode of transport in Frank Lloyd Wright’s Broadacre City proposal in 1932. For decades, Los Angeles required high-rises to have flat-roofs to enable helicopter landings. With advances in automation and controls, AI, and electrification, it’s getting closer. As drones become more widespread, the key technologies advance, and society’s willingness to tolerate a significant rise in air travel also increases. But it’s not likely to mix well with cities, in contrast with suburbs and rural areas, because of the crowding and high density. So it should emerge first where traveling fast and directly is more important, which are lower density areas with greater distances to be covered.

5/ What’s an important transportation issue that gets too little attention?

There are many issues that get too little attention, traffic safety you already noted. I’d add that even after we electrify the fleet and eliminate tailpipe pollution, cars will still pollute and be hazardous. Today air pollution from vehicles kills a similar number as crashes (which is about 1.3 million people globally). That’s not all tailpipe pollution. Brake linings and rubber tires wear out. Where do those particulates go? Your lungs. The water supply. All sorts of places they shouldn’t. And the better we make transport systems for people using cars, the worse it is for everyone else. For instance, traffic signal timings benefit cars at the expense of pedestrians in many cities. I’d also add police stops in the US in the name of safety are mostly unnecessary, lead to excessive deaths, and could be replaced with photo radar and similar systems.

Transportist: January 2022

The seventh January of the long 2016.

streets.mn at 10

When Bill Lindeke reminded me that streets.mn turns 10 round about now, I was sort of surprised, it feels both younger and older than 10 simultaneously.  In 1867, 154 years ago, the Minneapolis Tribune was founded, it remains with us today. Ten years ago streets.mn launched, so has been around for about 6.5% of the life of the Strib.  Will streets.mn be around in 144 years? Will the Strib?

We founded streets.mn back in the era of blogging, with the idea that all of us who wrote blogs about Twin Cities transport and land use issues would be get more views at one address together than at 10 separate URLs apart. That worked out reasonably well. For the first couple of years we had exponential growth in readership.  I was the Chair for the first 4 years (4 years longer than I wanted to be).

At first I imagined it would be a place to argue about the merits of topics like Minneapolis skyways or  arterial buses vs LRT (I hope the answer is becoming more obvious with the H line being planned ). Billions of dollars are being spent on transport infrastructure, and it is hard to believe it is being invested well.

But things took a dark turn. This is not so much because the world changed, though it did, but more because we became unavoidably aware (with a phone in every pocket, cameras, and social media) of how it always was.

Someone said the role of journalism is “comfort the afflicted and afflict the comfortable”. Streets.mn should agitate for more systemic change, this will inevitably afflict the comfortable. Very few people reading this would look around and see that everything is alright. We might disagree about what needs changing or how it should be changed, but it should not be that hard to agree on a few things that are the opposite of ideal.

I am disappointed to regularly seeing  Minneapolis on the forefront here in Sydney: Justine Diamond remains front page news. And Minneapolis claimed the front page world over with the murder of George Floyd. This follows the case of Philando Castile  in nearby St. Anthony.

Police on civilian violence is very much a transport and land use issue that should be within the purview of streets.mn. Foremost because this violence often occurs on public streets, and is justified by police stops purported to enforce traffic safety regulations. But the violence has a chilling effect on the willingness to use streets, to go places, to be able to access the amenities that cities uniquely provide. This kind of state-sanctioned violence, in which everyone is implicitly complicit, is far worse (per victim) than terrible epidemic of civilian on civilian violence which is also found in excess throughout the United States, and is yet one more aspect of unfortunate dysfunctional American exceptionalism.

The reason we build cities and transport networks is so that people can readily access people, places, and activities that they value, while maintaining their ability access other things in the future. Maintaining that ability means being able to do things at a low cost. That cost includes not only their travel time and monetary expenditures, but the costs they impose on society like pollution and carbon emissions. But it also needs to include both a feeling and reality of safety and security, the belief that anyone can make a trip and return in one piece, uninjured by either car or bullet and unharassed by police or other people.

When your great-grandchildren read streets.mn in 2165, will Minnesota have at least solved the problems of today?

Posts

Did software eat public transport?

We have seen numerous older technologies get wiped out as new technologies emerge: email ate the post office; TV, DVDs, etc ate the movie theatre; MP3s ate the record. Now old technologies still exist, a shadow of their former selves.

From 1918 forward, the automobile began to eat public transport in the US. The pandemic had something to do with it, but the lower costs and rising convenience of cars helped.  Transit had reached some stability by the beginning fo the 21st century. COVID has knocked it further for a loop, as CBD workplaces, one of the primary markets that transit served emptied out. But they emptied out because personal computers, mobile smartphones, cell towers, internet, software, and so on replaced some of the core functions of a workplace: doing office work (making virtual things: electronic reports, accounts, data manipulation, knowledge creation) and having meetings (discussing making virtual things , and occasionally real things). It turns out you don’t need to be physically anywhere to make virtual things, so long as you have access to the electronic network where such bits are moved from one side of the monitor to the other and the work is stored.

We may mourn the slow decline of office and public transit as we mourned the slow decline of department stores, shopping malls, urban factories, streetcars, which is to say, we won’t, except in some somewhat ironic articles in high-end magazines and blog posts.

Eventually we may mourn the suburbs, other worksites, and cars and highways, as they too are replaced, and everyone lives in a glass box on a cliff by the ocean with a electric gyrocopter on the roof.

Books

Now available for purchase in paperback or on Kindle: Applications of Access.

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Applications of Access edited by David Levinson and Alireza Ermagun

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Recent Student Theses

Recent Work by Others

News

The Greatest Mistake?

Perhaps modern US (and AU) cities’ greatest mistake was thinking of streets primarily as infrastructure instead of public space. We destroyed the space/place function for inferior infrastructure.

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