<br><div class="gmail_quote">On Thu, Mar 6, 2008 at 6:02 PM, John Eldon <<a href="mailto:j.eldon@sbcglobal.net" target="_blank">j.eldon@sbcglobal.net</a>> wrote:<br>
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<div><font color="#0000ff" face="Arial" size="2"><span>Shared
space is a great idea where traffic speeds are very low and can be kept that
way. I would not want to try this social experiment on Palomar Airport Road or
on the Orange County road in question. The increase in the rate of
rightward drifts coincides with increasing vehicle speeds, increasing driver
isolation in vehicle design, and increasing levels of sleep
deprivation among the general public. </span></font></div>
<div><font color="#0000ff" face="Arial" size="2"><span></span></font> </div>
<div><font color="#0000ff" face="Arial" size="2"><span>John
E.</span></font></div></div></blockquote><div><br><br></div></div><font color="#0000ff"><font size="2"><font face="Arial"></font></font></font>Hi John,<br><br>I understand what you're saying, but you're assuming that on high speed arterials the effect the bike lane stripe has on inhibiting motorists from crossing into the separated space on the other side of the stripe is greater than the effect a cyclist up ahead in the shared space of the motorist's lane has on being noticed and so not being hit by the motorist. It seems to me the opposite is true: the effect a cyclist up ahead in the shared space of the motorist's lane has on being noticed and so not being hit by the motorist is greater than the effect that the bike lane stripe has on inhibiting motorists from crossing the stripe, whether the bike lane is occupied by a cyclist or not, because of the significant role the attention-inhibiting stripe apparently plays in making the cyclist less likely to be noticed, coupled with the fact that the stripe is far from perfect in keeping motorists from drifting across it. Because the stripe is far from perfect, what's ultimately important in keeping the cyclist from being hit is for the cyclist to be noticed, and that's exactly what the stripe inhibits.<br>
<br>Your position is intuitive and quite popular, but it's not supported by any evidence I've been able to find. To be sure, the stripe does <i>encourage</i> motorists to keep left of the stripe - whether a cyclist is present or not; noticed or not - the unswept debris that collects in bike lanes is ample evidence of that. But that's not the whole story. The whole point of the shared space philosophy is that the flip side of the right-of-way clarity provided by the stripe is that it also reduces driver attention and care, and that effect needs to be accounted for as well.<br>
<br>Since I've been paying attention to this issue starting a few year ago, I have read or heard about far too many incidents of non-intersection inadvertent drifts into unnoticed cyclists (and joggers) in bike lanes or striped shoulders, and just one incident (rural Arizona with narrow lanes and rolling hills) in which a cyclist in a shared space outside lane was hit by an overtaking motorist. That doesn't mean there weren't some that I didn't hear or read about; I'm sure there were. So it's not definitive evidence, but from what I can tell it sure seems that overtaking collisions in shared space lanes are hit-by-an-asteroid rare, while drifts into cyclists (and joggers) in bike lanes and striped shoulders are all too common. In theory we know that this could be explained by cyclists using roads with bike lanes much more than roads without bike lanes, but we know that's not true in practice (there are just too many roads without bike lanes; roads used by cyclists). The attention-inhibiting effect of the stripe is the only practical explanation I have been able to find.<br>
<br>And it's not a social experiment that needs to be tried. The vast majority of roads in America (including in San Diego) already do not have bike lanes, and yet the incidence of overtaking collisions is practically unheard of on such roads in which the entire outside lane is shared space, especially if you don't count the crashes in which the cyclist is riding at night without proper lights/reflectors, the cyclist swerves into the motorist's path, or the motorist fell asleep.<br>
<br>But even in the incidents in which the motorist dozes and hits the cyclist, he must be dozing off and drifting just before he reaches the cyclist (if he had dozed and drifted earlier, presumably he would have crashed then). So if there is anything the cyclist can do to delay the dozing by just a few more critical seconds, it is to grab the motorist's attention before he is otherwise about to close his eyes for the final time, and, again, according to the shared space philosophy, grabbing the motorist's attention is exactly what is inhibited by ROW-clarifying attention/care-inhibiting stripes.<br>
<br>Here's a slightly different way to look at it. I think we want overtaking motorists to be a little bit stressed by our presence in the road up ahead, because it's that little bit of stress that causes them to take notice of our presence, slow down, adjust laterally, not get distracted, drift or fall asleep. That <i>bit o' stress</i> is what causes them to pass us consciously, conscientiously, carefully and safely. Isn't that what we want? The bike lane stripe works against us because it alleviates the very <i>bit o' stress</i> that would otherwise contribute to our safety.<br>
<br>Serge<br><br>NOTE: Any opinions expressed above are mine and not necessarily shared by any organization in which I am involved.