Monday, October 7, 2013

flagging segments: the case of the Hawk Hill backside

Yesterday I took advantage of an oh-so-precious closure of Conzelman Road in the Marin Headlands to ride the backside of Hawk Hill. While the road was "closed" in the sense of auto access, it was open as never before to hikers, walkers, and cyclists. The "closure" really revealed the potential for Conzelman Road, normally a congested, traffic-clogged tourist trap where drivers work their way through the numerous parking hotspots until they reach the top, get out of their cars, snap a few photos, get back in their cars, and battle the crawling traffic back down. This is all because the National Park Service, which oversees the Headlands as part of the Golden Gate National Park, operates under the policy that human legs are vestigial atavisms, and the only sort of meaningful human access is car access. Fortunately the people, young and old, enjoying the wonderful and rare serenity of the hill yesterday didn't buy into this 20th-century myth.

I, as did several others, took advantage of the wonderful lack of Federal presence by climbing the backside of Hawk Hill, the impressively steep east side of Conzelman Road, which due to the constraints of motor vehicles is one-way down-only. The road is plenty wide for bidirectional cycling traffic, and with the sharp and steep corners, descending riders need to be going slowly anyway. So I stuck to the extreme right, and rang my shiny brass bell when I approached blind corners. When I saw descending cyclists, I waved at them, just in case they failed appreciate my liberal interpretation of traffic law.

It was a worthy effort: initially, as I've been doing lately in efforts of this duration (around 6 minutes) tried to keep my power over 300 watts. But towards the top the road steepened, holding the increased grade longer than I'd remembered from descending. After what I thought was the top, more came into view. I came close to cracking, my power dropping as my legs became torque-limited rather than power-limited. Turning the pedals was an exercise in survival. My spirits were raised by two women, also climbing the hill, who cheered me as they chose the saner option of walking this section. I finally made it, wasted.

But the pain would be worth it, right? I'd at least get a solid time on Strava.

But it was not to be. Here's a segment of the climb: Kitty Hawk Climb Backside. And with it are listed those painful words: "This segment is ineligible for a segment goal because it has been marked as hazardous by another user." As I write this it's been "Ridden 113 Times By 106 People". Apparently they all survived.

What often happens in this instance is someone defines an equivalent segment, hoping the flagger's vigilance had waned. And so it wasn't surprising I observed a virtual copy: Hawk Hill Backside Climb. But it, too, has been flagged.

Flagging Strava segments is a controversial topic. The main issue is it's not a democratic process: all it takes is one user, of typically thousands examining a segment, to unilaterally decide the segment is unsafe, and he can flag it into oblivion. No amount of opinion to the contrary matters. And since there is a broad spectrum of what is construed to be safe, all it takes is one local extremist to render what the vast majority might consider a perfectly reasonable segment void.

My view: if going for speed presents a clear danger to other people, in particular pedestrians and/or juvenile cyclists, it should be flagged. On the other hand, if a segment presents a danger to the rider, that's his problem. We all sign a user agreement with Strava that we recognize cycling is intrinsically dangerous, and we are to use our own judgement about where to go fast and where to not do so. So a downhill segment such as the one on which Kim Flint died I would not flag. Kim was well into adulthood and should have realized that descending that road was dangerous. On the other hand, I would flag a segment on a popularly used pedestrian-only path. A mixed pedestrian-cyclist path is another matter, however. There I'm not sure.

The controversial issue is whether a segment needs to be safe always, or whether it needs to be safe at any time. For example, imagine a road which is heavily trafficked during weekdays at commute time, but which at 5:30 am on a weekend might have extremely small traffic. Of course it is dangerous to go plowing at top speed during the period of peak congestion, but should those with the motivation to ride it at the crack of dawn be denied the chance to see how their effort compared? We don't set speed limits for cars on highways based on what is safe during peak congestion: it is explicitly stated in the vehicle code that present conditions must be considered. The same principle applies to Strava segments.

Another example is a segment which goes through a traffic signal. Sure, you'd never hold a formal race on such a road without intersection control. But random users might get lucky and get the green light. In circumstances it may be perfectly safe to ride the segment quickly, assuming cyclists can't exceed the prevailing speed of motor traffic.

Stop signs are another matter. In the case of a long segment, for example an SF2G commute segment which will exceed 50 km, it is impractical to expect that there will be no stop signs along the way. But for a short segment, for example two blocks where between the blocks is a stop sign, running the stop sign at full speed would be critical to getting a high ranking. There I can understand why the segment might get flagged (although I have never done so).

So going back to the Hawk backside: riding this road, under rare circumstances, can be safe. It was far safer riding it yesterday, without any auto traffic, the "wrong" way then it is the "right" way with gaping tourists driving their oversized vehicles, admiring the views instead of the road ahead. So I definitely would not have flagged the backside of Hawk. Filbert Road in San Francisco also comes to mind: it's a one-way down street which is commonly climbed by cyclists in the opposite direction. There's plenty of room there for both bike and car and the principal risk is drivers pulling out of a parking spot, not anticipating uphill traffic. But the risk is almost completely to the cyclist, who on the 31.5% grade has virtually no momentum to present a risk to pedestrians.

Nothing in life is completely safe. Riding faster is arguably often riskier than riding slower. But driving faster is clearly riskier than driving slower, and we're a culture where driving quickly is not only accepted, but if one fails to do it, one is ridiculed and hated for getting in the way. So I think considerable thought should be given before flagging Strava segments. Perhaps, just perhaps, there is a valid alternate perspective to your initial reaction that the segment is a safety hazard.

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