This morning was one of
those mornings; when the alarm clock went off, I felt like throwing
it against the wall. Instead I turned it off and lay back down so
that I could ease into the day. I promptly fell back to sleep and
woke with an even bigger start some twenty minutes later. I let my
colleagues know that I would be late.
As we know random
events cluster – today they clustered at a railway near me!
I caught a later train
and as it rolled to a halt at its first port of call, the conductor
announced that we would go no further as there had been a crash
further up the line. The advice proffered, which I duly took, was to
return to the station from which we had just come and follow an
alternate route. Half an hour after I had left my local train
station I was back there waiting on an overcrowded platform for the
next train to Den Haag. As the scheduled departure time came and went
without any sign of our train, and the crowd of unhappy commuters
continued to swell, it was announced that there was a problem with a
switch near one of the main stations on our route. I rang the office
and let them know that I would be working from home...
My commute normally
consists of a ten to twelve minute walk, a train journey of some 46
minutes and a tram ride of not quite 15 minutes. Most days I can get
to work in about 90 minutes. The journey home is less
predictable because it starts with a tram journey – tram schedules
are not strict – and can take up to, and on the odd occasion more
than, two hours (the difference usually made up almost entirely
of waiting).
Why don't I drive?
Well, I don't have (nor have I ever had) a driver's licence. Besides
that pertinent impediment, there are the issues of gridlock,
congestion, pollution and carbon emissions. But I will readily admit
that if the only problem were gridlock I would without doubt have
converted to the car long ago. Travelling by car is generally quicker
and much more fault tolerant - if you step into your car 5 minutes
late at the end of the day, chances are you will be home 5 minutes
later than normal. If you leave the office 5 minutes late on the way
to catch a train, your journey home may end up being extended by a
half an hour or more.
If even well organised
and largely dependable public transport (as the Dutch system surely
is) results in significant delays at least a few times a month and
the freedom that travel by car offers all too often equates to the
freedom to sit idle in a traffic jam, what can we do to keep things
moving?
There are a few obvious
stop gap measures; teleworking may help somewhat in combating
congestion and should be considered a useful tool but its efficacy is
limited as teleworking is detrimental to team work. Flexible working
hours could reduce pressure on transport systems during peak hours
but any potential tends to be nullified by the demands of the rest of
our lives (opening hours for crèche, school etc. may not be
flexible) and here again, the issues that flexible hours raise when
working in a team are not trivial. Carpooling is another option but
it shares many of the drawbacks of public transport and can be
socially taxing to boot.
Traffic needs to flow,
maybe there are answers to be found in queueing
theory. Take my journey as sketched above; I tend to leave myself
13 or 14 minutes to get to the station in the morning even though I know it
generally takes around 10 minutes to walk the short distance
required. I have to build in slack – if I aim at arriving on the
platform as the train pulls in, an extra long wait at a traffic light
might be the difference between happily catching the train and being
left on the platform panting and cursing under my breath as I fumble
for my phone, my connection riding into the distance. The greater the
potential for variation in my journey to the station the more slack
I'm likely to build in to allow for the unforeseen. Hand-offs are
expensive.
More frequent trains
would alleviate my problem somewhat – I wouldn't be as worried
about missing a train if I could catch another less than 5 minutes
later. The rail-road has limited capacity however and a large
increase in the number of trains is not easily realised – unless
the trains were significantly shorter on average (smaller
batches). Thereafter cycle cost needs to be considered; the ratio
of manpower & material to customer-kilometres would limit the
extent to which batch sizes could be reduced.
If we were to remove
hand-off and radically minimise batch size, say to one traveller,
would we not simply arrive at travel by car? Yes. But. We still need
to consider WIP - Work
In Progress; allowing your WIP to rise above certain levels will
be detrimental to throughput, alternatively; maximising the use of
capacity (efficiency) will, after a certain threshold, reduce flow.
If you get out on to the motorway on time in the morning you can whiz
on through to your destination. If you're that little bit later, the
road is chock-a-block and although capacity is being used efficiently
(no. of cars per m2 of road), you will not be going
anywhere in a hurry.
In short, if we view
travel by public transport as the waterfall option (silos, hand-off,
long queues, large batches) and travel by car (as we know it) as the
chaos or cowboy option, does that offer up any agile solutions to the
traffic problems of the 21st century? Possibly. If there
were a system put in place to ensure that the capacity of the
motorway was never utilised beyond around 70%, the issue of gridlock
could be so atomised as to no longer exist. Cars would be allowed
onto the motorway via many slipways, managed centrally by a control system of traffic lights which would monitor and manipulate (motorway) utilisation, queue
length (on the slipways) and batch size (entering traffic). In that
way the motorway could actively pull traffic as opposed to playing
the proverbial gullet, packed so tight that it can only choke...
To complete the agile/lean allegory; there is even evidence that self-organising traffic is the safest, although I must admit that I'm not sure I'd like to be the one testing that hypothesis on a high-speed motorway.
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