Short Takes II: Improving Intersection Safety; Defining Lanes; Bus Prioritization

Some more thoughts about how to make it safer for cyclists to get through intersections, how we walk/ride on paths, and how to speed bus traffic through congested streets.

IMPROVING INTERSECTION SAFETY — Let Bikes Go When an Early Walk Signal Flashes

GETTING PEOPLE OFF CENTER — Paint Center Lines in Multi-use Paths

THE VEHICLES OF CHOICE – Why Buses and Bikes Are the Only Modes That Will Solve Urban Transportation Problems.

SPEEDING UP THE BUS:  Prioritization

  • IMPROVING INTERSECTION SAFETY — Let Bikes Go When an Early Walk Signal Flashes

Current best practice is to turn on an intersection walk signal 3 to 5 seconds before the traffic light turns green.  The “advance pedestrian interval” (API) allows pedestrians to get into the intersection and become visible to car drivers before car start moving – especially before they make a right turn – thereby giving the walkers greater priority and reducing the chances that a car will unknowingly turn into them.

Studies show that API works.  And because it gives pedestrians a greater feeling of having their needs met, they are less likely to get impatient and simply jump into the moving cross traffic.

But cyclists are just as vulnerable to car damage as pedestrians.  Cyclist safety would be significantly improved if they had a head start through intersections as well.  Bike boxes are one way to accomplish this – they allow cyclists to cluster at the front of a line of cars stopped by a red light so that they can start off and get through the intersection with less contention from cars.  A more controversial way is to allow cyclists to treat red lights as if they were stop signs, or even yield signs  – you have to make a complete stop but can then continue forward ahead of the waiting cars if there is no cross traffic.

But what if the law allowed cyclists to start across an intersection when the API signaled walk?  This would give cyclists a similar head start – not only as protection against right-turning cars but also to allow bikes to make safer left turns across not-yet-oncoming traffic.  Of course, right-turning cyclists would have to be held responsible for giving priority to pedestrians; but since both are standing next to each other, directly able to see each other’s presence, that shouldn’t be too difficult to do.

Why not?

  • GETTING PEOPLE OFF CENTER — Paint Center Lines in Multi-use Paths

I think every multi-use path should have a divider line painted down the middle.

People walk in the middle of the available space.  We all do it, usually unconsciously.  When I walk, jog, or cycle along the Minuteman or the Charles River paths or anywhere else, the pedestrians I come up to are invariably walking in the exact middle of the pavement.  Whether they are facing me or moving in the same direction, I have no idea if they will move to the right or the left.  It makes for awkward and even dangerous interactions, especially if I’m running or on a bike.

(And this doesn’t even address the fact that most of them have earphones and don’t hear my bike warning bell ringing or even my shouting as I approach.)

Fortunately, the same spatial dynamic occurs when the path has a line painted down the middle – although in this circumstance people invariably walk in the middle of their “lane.”  And this makes all the difference.

So long as they stay in one lane, whether or not they hear me coming, I’ve got room to pass.  I still slow down, just in case.  But the odds of them making a sudden movement, in a direction I have no way to predict, as they try to get out of the middle of the pathway…and thereby end up jumping right in front me as I pass….has been greatly reduced.

If a path is supposed to be multi-use, if it doesn’t have physically separate areas for fast (e.g. most bikes) and slow (e.g. most walkers) traffic, we have to make sure that it is structured in ways that minimize conflict and confusion between the uses.

  • THE VEHICLES OF CHOICE – Why Buses and Bikes Are the Only Modes That Will Solve Urban Transportation Problems.

According to the Nationwide Personal Transportation Survey, about a quarter of all trips made by the average US resident are under a mile; about 40% are less than two miles.  Even for those who commute, which is typically the second longest type of trip after vacation travel, about half go less than five miles from home.

But, in this country, over 80% of all trips five miles or shorter are done by car, usually carrying only one person.  Two to five mile trips are simply too long to walk – not that it’s impossible; it’s just that given our hectic lifestyle it usually takes too long.

What can government do that will get people to do something else?  What can people use instead of cars?  Buses and bikes.

We need vastly improved public transportation: trains, subways, trolleys, and lots of buses.  This is true both in suburban areas (which will also have to begin concentrating on mixed-use development in “village centers”) and in cities.

When the former mayor of Bogotá, Columbia, Enrique Penalosa, who became famous for creating a coherent bus rapid transit (BRT) system for that congested city, accepted a LivableStreets Alliance invitation to speak in Boston in 2009, he said that it was exactly where car traffic was most congested that it made the most sense to repurpose a lane for the exclusive use of high-speed buses.

But transit is large scale, relatively expansive and often politically controversial — although buses, even BRT systems, are a lot less expensive than subways or rail and therefore a more politically likely strategy.  Transit is also a relatively inflexible system – to be cost effective it needs to run on regular routes and schedules along heavily used corridors.

Most of those short trips are unscheduled runs to the store, or to bring kids to school, or to visit friends, or to do an errand of some kind.  They start at randomly-located homes and go to ever-changing destinations.  The needed flexibility is one reason why personal cars are so popular.

But bikes can serve the same purpose.  If our city’s roads were structured to make even relatively traffic intolerant cyclists feel safe, surveys show that the number of cyclists would quickly double or even triple – a projection whose validity is proven by the huge increase in bicyclists that appear on any street that gets even a simple bike lane.

According to the Bureau of Transportation Statistics (BTS) October 2000 Omnibus Household Survey, half of all Americans believe that cars, SUVs, pickups, and vans are the primary cause of air pollution in their communities and 38 percent feel that the availability of bikeways, walking paths, and sidewalks for getting to work, shopping, and recreation is very important in choosing where to live.

If we build it, they will come.

SPEEDING UP THE BUS:  Prioritization 

If we’re going to improve urban transportation, making bus trips faster and more comfortable is a top priority.

We need quieter and cleaner engines and interiors.  We need to know how long it will take for the next bus to arrive, and where it will go.  Once we’re on board, we need better information about what stop we’re approaching.  We need safer bus stops with more protective shelters.

We also need to bus to go faster.  One strategy is to reduce the number of stops.  Over the years, in response to user needs, stops have been added to many lines in front of elderly residences, hospitals or social service centers, shopping areas, and other high-demand destinations.  But having stops too close together significantly increases the total time needed for the route; there is a trade off between convenience and efficiency.

Another strategy is to move towards a Bus Rapid Transit (BRT) system in which buses have exclusive lanes, passengers prepay before boarding from raise platforms, and intersection controls are designed to let buses go through, and other rail-like features.  While I’m a big fan of BRT, it will take some effort to get beyond the miserable mockery of the concept provided by the Silver Line – so the politics of getting approval for a real BRT system will be difficult.

But what about that last idea – controlling intersections, meaning traffic lights, so that buses have absolute priority?  It would make a huge difference if some wireless system was set up to keep traffic lights green until a bus could get through.  Professor Peter Furth, at Northeastern University, tells me that there is a very complicated science about how to structure this prioritization – and LivableStreets Alliance is arranging for him to talk about this at a future StreetTalk.

But doesn’t the basic idea make sense?  Even car drivers might support this since the more people who take the bus, the less congestion they face.  What do you think?

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