Webster Road slip lanes Update #3 – June 25

Having seen the slip lanes at South Brisbane, this morning I decided to go and check out two other signalised slip lanes I’m aware of – one at the Grange and one at Sandgate.

Days Rd and Kedron Brook Rd, the Grange

The signalised slip lane at Days Road was built in 2018 when the roundabout was replaced. While I was impressed that there are pedestrian crossings on all three legs of the intersection, the slip lane signals are – surprise! – synchronised with the main traffic lights. I timed a maximum pedestrian wait at the slip lane of 45 seconds.

Rainbow St and Bowser Parade (very Mario Kart), Sandgate

The slip lane from Rainbow Street to Bowser Parade in Sandgate is certainly the oldest signalised slip in Brisbane that I know of, dating from around 2007. This slip lane is opposite Sandgate Station and sees significantly more pedestrian traffic than Days Road does. It is – of course – also synchronised to the main traffic lights, and I timed a maximum wait of 85 seconds. While timing I saw several pedestrians cross the slip lane, none waiting for the lights, and some running to catch the main crosswalk phase across to the station. I also, amusingly, watched a car sit and wait at the blank slip lane lights for an entire cycle, because the driver didn’t understand what the unlit signals meant.

Even if the engineers who design these slip lanes, and the politicians who sign off on them, genuinely believe they are safe, surely they must be aware that a long waiting time eliminates any chance of pedestrian compliance? I have been wondering why the Brisbane City Council synchronises their slip lane lights in this way, and the only theory I can come up with is that they’ve determined that driver behaviour makes it dangerous to allow the slip lane signals to change independently.

At all other intersections in Queensland, a yellow arrow signal only ever appears immediately after a green arrow at the end of a protected turn phase, when all conflicting traffic is being held by red lights. Therefore, most drivers interpret a yellow arrow as “the way is clear; hurry up before the light changes.” If this logic were applied at a slip lane, where the turn is permissive rather than protected, a driver hurrying through without paying attention could well collide with traffic on the cross road – if the signals were not synchronised to ensure a gap. I’ve put that theory to TMR, and asked if it was considered at Webster Road, but haven’t heard back yet.

As for the Webster Road intersection, the work there is almost complete:

The bin bags on the signal heads seem a little redundant: as they’ll be mostly unlit in service anyway, they’d hardly be more confusing for drivers now than they will be then.
“Provision of chevron marking at the corner of Webster Road to Gympie Road to stop drivers from using the shoulders to get to the slip lane,” clearly working as intended.

But that doesn’t mean my campaign has failed, or should come to an end.

Despite being demonstrably dangerous and anti-pedestrian, signalised slip lanes are becoming a de facto standard in Queensland, based on nothing more than wishful thinking that a safe alternative to slip lane removal exists. But it doesn’t.

And not only are these signals dangerous, but they’re expensive – about $250,000 per slip lane. That means hundreds of millions of dollars in public money could potentially be spent on a slip lane treatment that is no better, and quite possibly worse, than the known-unsafe treatments they replace. And that’s something worth trying to wake TMR up to.


PS: Here is TMR’s official response to my first letter, and my follow-up sent on Monday:

So what’s wrong with signalised slip lanes, anyway?

Many readers who are not habitual pedestrians, or who have not encountered a signalised slip lane in the wild yet, might be confused why advocacy groups are opposed to the signalisation of the slips at Webster Road. After all, won’t the signals make the crossing safer? Isn’t that why TMR is installing them? In this post, I’ll break down the issues around signalised slip lanes, and slip lanes more generally.

A slip lane is a short piece of road which allows nearside-turning traffic to bypass a signalised intersection. They are an exclusively North American and Australasian phenomenon, and are not used in the UK, Europe, or Japan.

The fact that some traffic at a busy intersection does not have to stop at the lights presents a problem for pedestrians trying to cross, of course. Therefore, in all Australian states and New Zealand, the road rules say that drivers must stop and give way to pedestrians crossing the slip lane. This road rule applies regardless of whether the slip lane is marked with a zebra crossing, with a signalised crossing, or with nothing at all.

Even without a zebra crossing, cars are supposed to stop and give way here. But they don’t.

Of course, anyone who’s ever tried to cross the road at an unmarked slip lane knows that drivers do not stop and give way to pedestrians. In some cases, motorists might not know their road rules, but for the most part it’s because they are busy preparing to merge onto the road they’re turning into, and are looking for conflicting traffic coming from the other direction. There’s simply too much work to do in too short a time to be able to effectively watch and respond to pedestrians.

Zebra crossings are one tool that has been widely used to try and fix this fundamental flaw. A zebra crossing, with large reflective signs and bold pavement markings, draws motorists’ attention back to the possibility of pedestrians crossing the road.

This has not been an unmitigated success. Motorists are still overworked and frequently miss seeing pedestrians, and pedestrians – emboldened by the presence of the crossing – are more likely to assert their right-of-way and step out in front of vehicles. Slip lanes with zebra crossings are dramatically over-represented in left-turn pedestrian collision statistics in Australia and New Zealand. And in recent years, improved safety rules for the construction of zebra crossings – including limits on allowable vehicle speeds and sight lines – have made marking zebra crossings on slip lanes impossible anyway.

That just leaves signalised slip lanes. A signalised slip lane has pedestrian activation buttons, red/green pedestrian lights, and signal lights for vehicles on the slip lane.

Stanley Place into Grey St, South Brisbane.

The default state is for the pedestrian light to be red, and the vehicle light to be off. Note that the vehicle signal heads do not have green lights. This is because motorists using the slip lane still need to give way, both to pedestrians crossing the slip lane and to traffic on the road they are turning into.

Signalisation is another attempt to fix the drivers-don’t-give-way problem: if they won’t stop for pedestrians, they can presumably be relied on to stop for a red traffic light. But it’s a very poor fix. Signalised slip lanes create a multitude of safety and compliance issues, including:

  1. Observing and obeying the signals adds to motorists’ workload, reducing their awareness of pedestrians even further. Most drivers will look first to the signal head, then turn to look for traffic, and not even think about people crossing the road.
  2. The road rules are contradictory. Drivers must give way, but the signals’ default state prevents pedestrians from legally crossing. This confuses and erodes everyone’s understanding of right-of-way at slip lanes.
  3. Pedestrians and cyclists won’t comply with the signals on such a short crossing anyway. With only a single lane to cross, most people won’t bother pressing the button and waiting for a walk signal, but will just look to see if anything’s coming then cross.

In short, nobody is going to follow the rules at a signalised slip lane – not pedestrians waiting for signals, and not motorists giving way to pedestrians – and that’s the hallmark of a truly unsafe design. The only reason we don’t know that signalised slip lanes are dangerous, the reason they’re not represented in the accident statistics, is that up until a few years ago no-one has been crazy enough to build them.

So why build them now, and why build them at Webster Road? As far as I can tell, the thought process goes like this:

  1. Unmarked slips are dangerous, and so not allowed.
  2. Slips with zebra crossings are dangerous, and so not allowed.
  3. We don’t know that signalised slips are dangerous, so they are allowed.
  4. Removing slip lanes is unacceptable to politicians.

Therefore, governments and councils signalise slip lanes, and will continue to do so until either 3) or 4) changes.

Hopefully it will be 4); either by convincing politicians that the community supports the removal of slip lanes, or by replacing elected recalcitrants at the earliest opportunity. If we’re waiting for safety standards to catch up with 3), then like all safety standards, they will be written in blood.



To take photos of signalised slip lanes for this post, I went to South Brisbane this afternoon. The signalised slips behind the State Library were built last year as “compensation” for closing Victoria Bridge, because apparently we can’t have one step forward without two steps back.

And even I, who knew they were bad in theory, was astonished to see what a total disaster the signalised slips here are in practice.

When I spoke to the lead engineer at Webster Road, one thing he assured me was that, because they’re not connected to the intersection cycle, signalised slip lanes are “pedestrian priority” and will immediately give pedestrians a green walk light when they press the button. I had my doubts about this, of course; there’s obviously always the delay of 5+ seconds while the lights change, and I was sure an additional timer would be added if the lights had been activated recently.

So I was keen to try this out in South Brisbane, and was expecting that, if I pressed the button a second time immediately after the lights had changed, I would have to wait 20 or 30 seconds for another walk signal.

So imagine my surprise to discover that the slip lane lights at South Brisbane are synchronised to the intersection! The slip off Grey St will only give pedestrians a walk signal at the same moment the Stanley Place traffic lights go green, and the slip off Stanley Place will only give a walk signal with the traffic on Grey St.

This means crossing this intersection legally would take pedestrians several cycles of the lights to get the three walk signals in sequence, and the maximum wait time I measured for the Grey St slip lane was – wait for it – 95 seconds.

Would you stand on a traffic island like a goose for a minute and a half, instead of just crossing the slip lane and getting on with your day? Neither would this guy, and neither would anyone else.

I was at South Brisbane observing the intersection and taking photos for about half an hour. In that time I saw:

  • About a hundred pedestrians cross the slip lanes, with practically 0% compliance with the signals. A few pedestrians pressed the button, waited for a few seconds, then gave up and crossed anyway. Most pedestrians just ignored the signals completely.
  • Several drivers get halfway down the slip lane, then slam on the brakes, look confused, and very cautiously creep around the corner. Because what does a blank signal head mean? Who knows…
  • At least two drivers RUN THE RED LIGHT at the pedestrian crossings: one who stopped to let a pedestrian cross, then drove on before the signal cleared, and one who just sailed through the red arrow without stopping at all. Because expecting drivers to watch three things at once – pedestrians crossing, a signal light, and conflicting cross-traffic – doesn’t work and isn’t safe.

So if anyone’s still in any doubt that signalised slip lanes are a terrible, horrifically dangerous idea, head down to South Brisbane some time and watch them in action. Just try not to get run over while you’re there…

– D

Webster Road slip lanes Update #2 – June 14

I went for a walk down to Webster Road this afternoon, where the Brisbane City Council and TMR are extending the North Brisbane Bikeway. The ramp widening on the western slip island is almost complete, while the eastern island is a mess of temporary tarmac – still no signs to indicate to pedestrians what’s going on, of course.

(The bollards on the far side of the intersection are not part of the bikeway works – they’re repairs from the latest all-too-frequent car crash).

But perhaps what’s most alarming is there has been no marking or cutting around the existing pedestrian crossing across Webster Road, which currently features absolute-minimum-standard 1.2m kerb ramps and a nice big stormwater drain jutting into the crossing in the middle.

This is meant to be part of the North Brisbane Bikeway, remember – it’s quite a contrast to the showpiece photos on TMR’s website! This is not a crossing that two cyclists can safely pass each other on, let alone the kinds of groups – families on bikes, with dogs, or with kids in strollers – that one commonly sees using the paths around Marchant Park.

Upgrading a signalised intersection with a bikeway crossing is not rocket science: you remove slip lanes, and you widen the crosswalks to allow pedestrians and cyclists to cross safely and simultaneously. In recent years, BCC and TMR have mostly managed to do this – from Woolloongabba to Wooloowin. So what’s gone so badly wrong at Webster Road?

It’s been three weeks since I wrote to the Minister’s office about my concerns with the Webster Road crossing, and two weeks since I was told a formal reply was being drafted. I phoned and emailed Nic at TMR today to find out how that was going, as well as to confirm that there are indeed no plans to widen the crosswalk as part of the current project, but she did not get back to me. I’ll update this if I hear from her tomorrow. (EDIT: the current crossings not being upgraded has now been confirmed, and I’m expecting the formal response later this week).

In general, getting any information from TMR about the bikeway at Webster Road has been difficult: their attitude seems to be that it’s “minor works”, so they’re not obliged to tell anyone anything about what they’re doing. It’s horrifying to think, but was avoiding public consultation a factor in the planning decisions? Maybe Right to Information can shed some light – however long that process takes…

(They have built an oversized concrete apron around the signal control box though. There’s priorities for you).