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Specialist local speeding solicitors
UK Road Sense, Dorset Way / A3049 50 limit
Fleetsbridge Roundabout Traffic lights - a
proper analysis - traffic lights probably INCREASED accidents
There is not enough information to be certain about
anything, other than one thing: to claim that the lights have reduced accidents
from 7 to 2.68 (which seems to be the ONLY justification from Poole Council) is
clearly complete nonsense:
Event rates are low, random variations high
Important factors such as traffic volumes / distributions, general
trends, changes in reporting, have not been considered
Other changes at the roundabout (road markings, effects on journeys by
changes at the many nearby large stores), etc have not been considered
However, if we are to believe that the accident
counts have been influenced predominantly by the traffic lights, one thing
(only) sticks out like a sore thumb: if you include the few years of data PRIOR
to the original installation of the lights, the original installation (full
time) in June 93 saw an INCREASE and when the lights were switched to part time
in Nov 95 accident counts increased again significantly. Obviously, comparing 2
periods with 7 years between them when many things have changed is a lot less
reliable than comparing the 3 years directly before and after - and this shows
When the lights were switched back to full time from
Nov 2000, accidents did fall significantly – but ONLY back to levels that might
have been expected anyway if the lights had never been there (as illustrated by
the curve). And you can reduce accident counts in one area by reducing flow, but
those accidents will probably just happen somewhere else.
The minimal reductions seen could probably be
achieved just by reducing flow by some other means, reducing number of / widening lanes, etc, a bit of paint
instead of expensive traffic lights that cost drivers and the environment 24
hours a day. This would not reduce flow at all when traffic is light and would
limit flow, vehicle density, make it easier to join leave the roundabout etc
thus reducing collisions when busy.
There are other ways to reduce accidents: proper
policing would be the most effective way. Even if the lights have reduced
accidents, it does not mean it is the most cost effective and efficient way of
doing it. All options should be properly considered.
So a proper analysis using all available data and
looking at the wider picture can only conclude that the overall “experiment” to
install traffic lights on this roundabout has caused more accidents than it has
prevented, not to mention all of the congestion, pollution, wasted time and fuel
for thousands of drivers every day.
Even despite the uncertainties mentioned in 1 above,
the accident increase during part time operation looks undeniable. This
surprises even me, perhaps there is an explanation for this, maybe the presence
of lights gives drivers a false sense of security, without the control if they
are switched off. Perhaps speed limits / humps / loads of road signs etc. have
the same effect. Perhaps it is better to allow drivers to think a bit more about
their driving rather than blindly following increasing numbers of rules and
control that seem to have no reason (but can of course generate revenue).
reassuringly, a proper analysis supports common sense: it’s a roundabout, it
does not need traffic lights to improve safety OR help with traffic flow.
It is truly worrying that our “experts” can get
things so completely wrong, and draw the conclusions they want, to do what they
want, by such naïve and simplistic interpretation of data. And these are the
same “experts” presumably who are deciding on new town bridges, road safety,
speed limit reductions, other road “improvements”, etc. No wonder we’re in such
a mess. When are things going to change in Poole / Bournemouth / Dorset?
The best course of action now at Fleetsbridge is to
simply remove the new traffic lights and sell them for scrap, and to learn from
the failure and to not repeat it. Please can Poole Council do this or provide a
proper scientific justification for the lights.