Friday 9 January 2015

the design floor

Have you ever looked at or stumbled across something that made you wonder who had designed it, because the design was so obviously flawed that the only rational deduction to be made was that the designer was either insane or stupid, or both? It’s a feeling that I experience a lot, but my latest encounter with poor design leaves me incredulous, and also mystified that no one seems to have foreseen the problems it would create.

Public transport between my village and Fanling railway station is inadequate at peak times, so every weekday morning around 8 o’clock I drive Paula to the station. Once we have joined Sha Tau Kok Road, the first junction we encounter is the one shown in the following diagram, to which I’ve added compass points for the four roads feeding into the junction to make the problem easier to describe.


Work to modify the layout at this junction had been in progress throughout last winter and was finally completed during the summer. Basically, all that has been added are left-turn lanes from Sha Tau Kok Road in both directions, and the right-turn lane from the northeast has been lengthened. However, in the original layout, locals driving from the northeast knew to join the much longer queue in the left-hand lane, because the right-hand lane was blocked by traffic waiting to turn right. Curing this problem is the likely motive for changing the light sequence, but this has had unexpected consequences.

To illustrate the problem, I need to compare the old and the new light sequences. This is the old sequence:
1. Traffic from NE (left turn and straight ahead only); traffic from SW*.
2. All traffic from NE; traffic from NW (left turn only).
3. All traffic from NW.
4. All traffic from SE.
5. Universal pedestrian phase.
* Turning right is forbidden if coming from the southwest.
 This phase is activated only if someone presses the button—a given at this junction.
And this is the new:
1. All traffic from NE.
2. All traffic from NW.
3. All traffic from SE.
4. All traffic from SW (right turn prohibited).
There is no universal pedestrian phase in the new sequence, so pedestrians and cyclists negotiating this junction have to do so piecemeal, which is especially frustrating if your eventual destination is diagonally opposite your starting point. However, the first flaw in this arrangement drew my attention immediately: up to 90 percent of the traffic from the northwest, southeast and southwest (phases #2–#4) exits the junction to the northeast, and the next set of traffic lights is only about 300 metres away. Although the lights at this next junction are heavily biased towards traffic on the main road, here the pedestrian phase—if somebody has pressed the button—is quite long, and when this occurs traffic invariably backs up and clogs the junction that is the subject of this analysis.

If this had been my only criticism of the changes, it could plausibly be argued that one problem had been resolved (turning right from the northeast), and the replacement problem is not as serious. However, there has been another consequence of the changes that is dangerous and that needs to be addressed urgently. Traffic from the southeast, which will have come through Fanling’s industrial district, continues to pour out of the unnamed road up to 15 seconds after the lights have turned red! Some of this traffic is 40-foot container trucks, and some is smaller freight vehicles, but this lawless flow also includes coaches, minibuses and private cars, a point that I will return to presently.

This phenomenon (see photos below) only occurs during peak periods; during the day, there is sufficient time for all the traffic that is waiting its turn to get through the junction while the signal remains at green. This nonchalant red-light jumping is new; it never happened under the old system, and I think I know why.

Note that under the old system, phase #4 (traffic from the southeast) was followed by a universal pedestrian phase, so within a second or so of the little green men appearing on eight separate crossings, the junction was swarming with pedestrians and cyclists, many of whom were crossing the junction diagonally. Even an inveterate runner of red lights would think twice before finding themselves having to explain how they came to knock down several people who had decided to cross on the quite reasonable expectation that they wouldn’t encounter any traffic because all the little men were green.

Unfortunately, this incentive to stay behind the stop line once the red light has appeared no longer seems to apply, because traffic from the southwest, whose turn it should be, can be relied upon to wait patiently until the illicit backlog has cleared. But why should this behaviour have developed? And why is it so blatant? I return to an analysis of the traffic types, particularly the cars, coaches and minibuses, that emerge from this road. Where have they come from?

Anyone driving up from the south or from the other side of the railway, if they are not familiar with the lie of the land, will follow the conventional, signposted route, which involves turning right onto Sha Tau Kok Road at a light-controlled junction that isn’t particularly generous with the time allotted to traffic wanting to make this manÅ“uvre. Driving through the industrial district avoids this junction, and a second set of traffic lights, before joining Sha Tau Kok Road. Clearly, such drivers have already developed a time-saving mindset, which translates into thinking that they still have time to cross the junction even though the light turned red several seconds ago.



This sequence of photos illustrates the difficulty of adequately recording this phenomenon. You have only my word that the black van in the first photo was behind the stop line when the light turned to red. It could have just turned, making this vehicle's position legitimate. However, it is easy to deduce that the yellow truck would have been crossing the stop line as the light changed. So where does that leave the driver of the black car in the third photo, who would have had more than enough time to stop?

This system has now been in operation for several months, and I would be astounded if the police were unaware of the current situation. But this would imply that they do know yet choose to do nothing about it. And what about the anonymous official who designed this new light sequence? Surely they would have been aware that the road through the industrial district is used as a rat run by local drivers and should thus have anticipated the possibility that those same drivers might disregard the lights. And did anyone think to tell the police, and/or the Highways Department, that the sequence had been changed and could someone monitor the situation for problems?

Soon after deciding to write about this phenomenon, I happened to see a public service announcement (PSA) on one of the local television channels reminding drivers that ‘we stop on amber’ and warning them that they faced a $500 fine (and five penalty points on their licence) for running a red light. In Breaking the Law, I highlighted the strange situation that exists on public minibuses, where passengers are warned that they face a fine of $5,000 (and three months in prison) if they fail to fasten their seat belts. Both warnings are equally often ignored, but it does seem bizarre that the authorities regard an act of stupidity that can only impact on the perpetrator as being ten times more serious than an act of stupidity that can result in someone else being killed.

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