Welcome back to Sunday Reading.

Housing is on my Sunday Reading agenda for 2018. Here’s an epic article covering a new bill filed in California by State Senator Scott Wiener of San Francisco. Wiener proposes a blanket upzoning of transit-adjacent properties across the state. The bill will amplify the conversation about how our dated zoning laws are stifling urban productivity and exacerbating inequality. I predict it will take 10 years to get rid of the anachronistic concept of single family/house zoning. In big, growing cities, it will happen much sooner.  Dante Ramos, “Go on, California — blow up your lousy zoning laws“, Boston Globe.

A state senator from San Francisco recently filed legislation to sweep away minimum-parking requirements, limits on density, and certain other restrictions on residential housing construction within a half-mile of a train station and a quarter-mile of stops on high-frequency bus routes. Senator Scott Wiener’s bill would promote bigger, taller new buildings in transit-rich urban areas across California.

The bill may be the biggest environmental boon, the best job creator, and the greatest strike against inequality that anyone’s proposed in the United States in decades.

Here is Wiener’s response to the initial feedback received from the bill.

Scott Wiener, “My Transit Density Bill (SB 827): Answering Common Questions and Debunking Misinformation“, Medium.

To be clear, in terms of the big picture:

  • The only way we will make housing more affordable and significantly reduce displacement is to build a lot more housing and to do so in urbanized areas accessible to public transportation (along with investments in affordable housing and strong anti-displacement protections).
  • The only way we will meet our climate and air quality goals is to build a lot more housing and to do so in urbanized areas accessible to public transportation.
  • The only way we will continue to grow California’s economy is to build a lot more housing and to do so in urbanized areas accessible to public transportation.

This is a fascinating article positing why a rural intersection has such a terrible safety record. Bez, “Why This Type Of Road Junction Will Keep Killing Cyclists“, Single Track World.

Hidden In Plain View
Far and away the most plausible answer is a phenomenon known as “constant bearing, decreasing range”, or CBDR. Originally noted by sailors, it is the phenomenon whereby two vessels, or vehicles, moving at steady speeds in straight lines towards a collision will maintain the same bearing.

If you’re a dab hand with basic trigonometry, you can probably figure the principles out for yourself, but if not then of course Wikipedia has an explanation.

CBDR is required knowledge in maritime and aviation, where ships and aircraft travel significant distances with constant speed and bearing, but it is rarely taught in the context of highways, where motion is generally less constant. But it is nonetheless important where two straight routes cross: not just two roads, but also where roads and railways cross at unsignalled level crossings (a design which is rarely if ever found in the UK but which is not uncommon in parts of the US).

Sailors and pilots are taught to detect ships and planes at a constant bearing and to take avoiding action. When it comes to drivers, however, things are very different, because almost all motor vehicles have a design flaw which means not only that a CBDR condition precedes a collision, but that unless (as we shall see) the driver does one of two things, the same condition means that the driver will never even see the phenomenon occurring.

That design flaw is the front ‘A’ pillar, at the edge of the windscreen.

The promises made by boosters of AVs are eerily similar to the ones made by those supporting urban motorways and priority for cars over pedestrians. William Leimenstoll, “An “Unprecedented Mobility Revolution?” We’ve Been Here Before“, ENO TRANSPORTATION WEEKLY.

“They are designed to make automobile collisions impossible and to eliminate completely traffic congestion.” Norman Bel Geddes, Magic Motorways, 1939.

“[It] has the great potential to enhance public safety and mobility, reduce traffic congestion, and advance transportation efficiency…” David L. Strickland, Counsel, Self-Driving Coalition for Safer Streets, 2016 Congressional hearing.

While these two quotes are largely interchangeable, they describe two different technologies in two very different eras. If you switch the publishing years and the technology named, many articles extolling the virtue of automated vehicles (AVs) would be remarkably indistinguishable from those supporting urban freeways decades ago.

The rise of urban freeways offers a number of lessons on how to manage new transportation technologies. AVs promise changes on a wide scale and, depending on how they are rolled out, could have positive or negative effects on communities and the environment.

Agence France-Presse, “France cuts speed limit on roads after alarming rise in deaths“, The Guardian.

The French government said on Tuesday it would lower the speed limit on two-lane highways to 80km/h (50mph) from 90km/h, hoping to reverse an alarming rise in road deaths.

Several previous governments had toyed with the idea as a means of reducing highway deaths, which reached nearly 3,500 in 2016, but backed off in the face of widespread public opposition.

About 55% of those deaths – 1,911 victims – occurred on the 400,000km of so-called secondary roads across France, two-lane routes with no separating guardrail.

“Excessive or inappropriate” speed was involved in 32% of those fatal accidents, which far exceeded those in urban areas.

The government says the lower speed limit could save 350 to 400 lives a year.

Detail of architectural model of the Auckland Urban Motorways ‘Harbour Skyway’, Sir George Grey Special Collections, Auckland Libraries, 580-4218

A couple weeks ago I linked to this website RINGWAYS that catalogs all the unbuilt roading schemes in London. This Guardian article documents the international motorway projects that were stopped in their tracks by freeway revolts.  Douglas Murphy, “Unbuilt cities: the outrageous highway schemes left as roads to nowhere“, The Guardian.

Of all the mistakes made by city planners in the postwar era, the passion for highway construction has to be one of the most foolhardy. After the early success of systems like the autobahn and freeways, cities everywhere were carved up to make way for giant roads, crashing through neighbourhoods and creating opportunities for “comprehensive redevelopment”.

This was considered progress, a necessary part of entering the modern world. But some strange things happened – the most damning being that these new roads didn’t reduce traffic at all. Instead, they induced demand, clogging up almost as quickly as they were built. As time went on, communities began rejecting the plans and fighting back against the bulldozers, halting development in its tracks and kickstarting the modern conservation movement.

That’s it for this week. Please add your links in the comments section below.

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  1. In the example of an intersection, reducing the speeds, and reducing conflict is desirable so a roundabout would suffice.

    1. In 1988 when I was a young engineer who knew all the answers I was having a beer with the retired City Traffic Engineer who had left the council before I started. I told him what we really needed was more roundabouts and fewer traffic signals as they were safer, more efficient and had almost no ongoing costs. He smiled at me and said ‘Yes mfwic all a roundabout needs is a man with a good stiff broom to sweep up the glass!’

      1. A street near us has a succession of roundabouts. Judging by observation of driving habits it seems that many believe it is the laws of physics that determine how to drive roundabouts. The practice seems to be that the faster they traverse the roundabout, the less time they will be on it, and therefore the less chance of being hit. Unfortunately more and more recently the law of probability is coming into play and greater volumes of traffic are increasing the chance of piles of glass.
        I suggest that this is not a reason to remove roundabouts but rather the source of the problem, the offenders license..

      2. If ’roundabout’ is ever suggested or discussed, we need to use the terms ‘good roundabout’ or ‘bad roundabout’. We have plenty of the latter around, to give the species a bad name. Good roundabouts are not particularly difficult, with a bit of thought and effort. It is also remarkably easy to make them safe for people on foot or bike, if care is taken. And having a broom handy is much better than needing an ambulance on call.

        For the oblique crossroads in the original post, a staggered intersection is the obvious answer for the New Forest. It would also be the best answer for a lot of NZ rural crossroads where a roundabout is not necessary (with low volumes of crossing traffic), desirable or practicable.

        Requiring a vehicle approaching on the minor road to slow down (whether traffic is on the main road or not) breaks the constant angle, decreasing range syndrome. It also makes it easier to take avoiding action (stop, swerve) when the unexpected appears.

        If you want to design a deadly intersection, you can hardly do better than a crossroads.

        1. There are no good roundabouts in an urban environment- they are all space hogs.
          I still don’t get why they don’t run a red LED strip on the road at traffic lights surely you couldn’t miss that.

      3. Round about only good for low traffic.

        They are inefficient and create massive congestion when traffic volume are large.

        Examples are albany motoway on ramp roundabout. Panmure Round about. Royal Oak Round about. Greenlane Round about.

  2. I guess with pillar posts, they’ve been getting bigger to improve car occupant safety, and possibly to cope with more sloping windscreens for aerodynamics. Plus have they moved forward a bit to create cheaper windscreens that don’t wrap around so much? In which case cyclist safety has been compromised for car occupant safety, aerodynamics/fuel efficiency and cost.

    1. “I guess with pillar posts, they’ve been getting bigger to improve car occupant safety,”

      Hole in one.
      Apparently the issue stems from US.

      The reason for this is that the US safety rules changed 20+ years ago and required that in any rollover accident that the vehicle roof must not deform into the cabin and must be able to bear the vehicle’s weight if underside down.
      [Partly in response to all those “top heavy” SUV rollover accidents that started happening in the ’90s I expect].

      This means in effect all the manufacturers decide that this means you have to have massive steel pillars holding the roof up in all cars built in the last 20+ years.

      Hence why the A pillar are so large, causing these large blind spots.

      Because what is needed for the US tends to end up in all the cars we get here eventually even if we drive on the other side of the road.

  3. Hidden in plain view!

    The A pillar blind spot is real and potentially lethal.

    The rake and thickness of the 2006 – 2017 Holden Commodore VE and VF model A pillars are so bad they do block out pedestrians and cars altogether and it is bloody chilling when it happens to you as the driver.

    The obstruction to ones vision is such it truly hampers safe 90 degree turns and renders tight turns over 90 degrees almost vision-less. Similarly its B pillar (between the front and rear doors) is so gigantic your quick look over the shoulder when lane changing, as one should always do, is also blacked out. It is a car with appalling visibility for the anyone inside.

    Quite how manufacturers who are fitting 6 + airbags and all other manner of safety equipment to reduce harm, then design in such major safety flaws such severely reducing vision for styling purposes, is beyond me.

    1. This [zoomable] image linked here, also from the Whites Aviation collection in the National Library digital archives shows the opposite view, looking over the same Grafton area, but towards the cameras “eye” in the above photo, but this one was taken prior to any motorways being built. Probably late ’50s early ’60s – after the trams, but before Motorway construction madness had commenced.


      Imagine what a major public park/open space Grafton Gully would be today if we still had it like that – instead of burying it under earth and concrete. And putting a girdle around the CBD as we did so.

      Also note, you can plainly see the [trolley] bus stops along Symonds St where the bus stops are now beside the future motorway on ramp. So it seems buses stopping there is not a recent thing.

      Of course they’re just not that close to anything really. But prior to the motorway severance you could have easily walked to all sorts of places in a 10 minute walk, including most of K’Rd and no doubt most of the Upper Symonds St shops/work places.

      You can also see in the top part of the same photo the beginnings of the major encroachment into the harbour – where the former AHB [now POAL] Fergusson container terminal is located now.
      And see how much more open the harbour was back then.

  4. While the suggestion on uncrossing the T’s of the crossroads is suggested as a solution for the cycle road safety problem at this kind of rural intersection, it does come with major costs and potential land constraints issues that may be tricky. However, I’m not convinced that it is always the A-pillar blind-spot or the constant-bearing optical illusion that is the issue.

    The other factor is WHERE approaching drivers are looking for main road traffic; at highway speeds it will be a fair way down the road. The problem is that a (slower-moving) bike rider is closer to the intersection, but drivers may not think to look there. This problem has also been identified as a crash factor in NZ at roundabouts with good corner sight distance; drivers are looking far off to their right for a car they might have to give way to, and not at the cyclist who may just about be upon the roundabout.

    A couple of sites in NZ have used screens or shade cloth on the approaches to limit the inter-visibility sight distance from further back and ensure that side road traffic slows down and checks properly at the intersection before they move off.

    1. Best solution is to ensure that potentially conflicting vehicles are approaching on similar bearing and at similar speeds. We can do this with roundabouts, especially urban single-lane ones, by using geometry that brings car speeds down to cycling speeds. And not putting cyclists into the edge of the circulating lane (off to the right and out of sight).

      Rural crossroads may best be solved with a stagger, though land issues must be tackled. Urban crossroads can often be given a UK-style mini-roundabout, if nothing else is practicable, which will often be effective.

  5. On the subject of AV and Ride Hailing as solutions:

    Heres a couple of stories from City Lab about NYC finally, maybe, just maybe, getting ready for Road Pricing.

    This one:


    calls out Uber, Lyft and Via (all ride hailing/”Transport Network Companies”) – the kinds of companies we keep hearing are the “solution” to whatever transport/mobility problem you care to name, as specific problems to the growth of congestion in NYC.

    The fundamental problem seems to be that too much of these “mobility as a service” vehicles are running empty, i.e. “deadheading”, between jobs. Resulting in lots more congestion but only a slight improvement in mobility overall. 36% increase in congestion in 7 years is cited due to these operators.

    Because of this, NYC might finally have to implement road pricing and [hopefully] use the money raised to fix PT properly so it can actually compete and do what Lyft/Uber et al simply cannot – remove vehicles off the road.

    And this one talks about that:


    Of course, like it is here, the argument is usually that you need to fix the PT before you price the roads or folks have no options to move around. Which is true, but if you keep delaying the inevitable, then at some point, you have to actually do something about road pricing – whether the PT is fixed or not, and it seems NYC is at, or close to, that point now.

    We’d be very smart to learn those lessons now, second hand, not first hand, instead of waiting as we usually do until enough “overseas experts” tells us “this is what is needed”. So that we finally do it – as late, as pro-car, and as half-arsed as possible. Like we did with the original motorways, which we supposed to be done only after the rapid transport network was fully implemented.
    Few of the motorway proponents ever remembered that condition/requirement in the rush to embrace the future.

  6. Unfortunately the photos of the car pillars are misleading. Not saying there is not an issue as larger pillar obviously results in larger blind spots however in these photos they are not taken from the drivers view and if you look in detail are not consistent with the point of origin of photos between cars. Just look at the road signs in one photo and not the other to indicate the angle. In fact the 2005 photo is more like it was taken in the passengers seat.

    1. I can’t remember – were the side windshields a problem for visibility too? I did like them because they kept the wind off your face but allowed a breeze through the car.

      We need some better graphics than those pictures, agree. They look more appropriate for showing how a passenger has a blind spot – or, a driver has a blind spot on the passenger side. Yet the A-pillar problem is quite real.

      1. Yes the passenger side pillar is the real issue to the driver. Just sitting in 3 different newish vehicles I do not believe from a drivers perspective that the drivers side pillar has too much effect on viewing traffic to the right as it is nearly right in front however to the left side is a significant blind spot caused by the pillar.

  7. I don’t think the rezoning goes far enough. Much of today’s intensification will require demolition within the lifetime of the structures being built. Planners need to be looking at Singapore and Hong Kong for what the future will bring. At least the immediate areas around PT nodes should allow for 30-50 story towers

  8. The A pillar blindspot is a function of windscreen angle and distance from the dash. It’s practically non-existent in a Mini but it makes driving GM/Ford sedans terrifying. Everyone should be driving curved cockpit LMP1 derived sportscars instead.

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