The anatomy of an intersection

Brookfield – the red, yellow and green jungle.

Christchurch started it. And Tauranga finished it.

It's about traffic lights and one-upmanship. In the Garden City – Christchurch – they've been saying 'kinda overkill”, questioning the need for 19 traffic light poles to control just one intersection in their CBD, where before the earthquakes there was none. That's $8500 for each of 19 poles to control a meeting point of trams, cycles, pedestrians and vehicles.

If it was a contest, Tauranga would win. With piles of traffic standards to spare.

'Tauranga has plenty of intersections where we have at least 20 traffic lights,” says Haydn Wardley, the go-to man about traffic lights at the Tauranga Traffic Operations Centre. 'And another one in Rotorua, which we also look after,” says Haydn, who works for Tauranga City Council.

Then there's Haydn's red, yellow and green magnum opus – his own grand design, the Brookfield lights, thirty-five poles and many more lights, scattered strategically of course, over a sprawling piece of suburban real estate claimed by cars.

'Thirty-six poles actually,” corrects Haydn.

He should know. He designed and strategically placed each pole, sweated for six months to bring some order and flow to the chaos that had been the Brookfield interchange. There's the convergence of a whole lot of roads, there are many residences, multiple driveways, a shopping centre with four or five accessways in and out, there's a school and there are pedestrians.

'The peanut-about,” says Haydn. 'A roundabout with an intersection on the side – shaped like a peanut.”

When he saw Brookfield for the first time, when he took on board all the complications, it was a ‘bloody hell' moment. 'Very much so because of the tight land restrictions. We would have had to buy up enormous numbers of houses to get a normal intersection in there. Cost implications and the land – it was an impossible task actually.”

The engineer still can't believe what he managed to do. 'We saved millions on that build, a separated intersection would have cost five times as much.”

There were lots of different designs. 'But the biggest problem was convincing people, convincing everyone that I was right,” says Haydn. Self-assured, but there were a lot of sleepless nights.

'You design it on paper, you go on-site a lot and then you tweak things and change them again. 'Brookfield was about getting it absolutely right, getting it perfect.” Does he think he nailed it? 'Yes, very much so. People really like it. They are gobsmacked because they know what we have resolved.”

Not everyone though. One local likened Brookfield to the outcome of a birthday party where sugared-up, blind-folded kids played ‘pin the traffic light on the intersection'. The engineer did field a lot of questions and a lot of complaints. 'But it was a ‘dog' beforehand and afterwards people couldn't believe how well it was running,” says Haydn. 'And it still does today.” Three sets of red, yellow and greens in every direction of every lighted segment of the interchange. Many standards and many, many lights.

'That's the rules, they have to be clearly visible to the driver, a minimum of three but you can have four or five.”

And those lighted segments are jammed in. 'Everything is so close, you are sitting on a stop line and wondering about the lights in front of you. Are they for me or are they for you?” So it's been designed ergonomically – some of the lanterns have been twisted slightly so they can't easily be seen from a side view. Only if you turn your head. And again, for drivers looking straight ahead, the lights have been reconfigured downwards so any confusion is minimised.

Which is why the Brookfield and two others of Haydn's babies are unique in New Zealand.

The phasing of lights at all other intersections are regulated by sensors in the road. They are triggered by the metal in vehicles and change depending on the flow of traffic. Not Brookfield, Maungatapu and Welcome Bay. They are programmed for a specific time of the day, morning peak-time, lunchtime, afterschool – and it doesn't change.

'They only know it's four o'clock or ‘whatever o'clock' and will run a certain sequence. So it's fixed.”

It's designed that way because there's only so much room behind each stop line. 'I only want the phase to run 10 seconds, I don't want the signals to give any more time.”

Otherwise the traffic backs up and clogs the intersection. Or there can be traffic from one section still clearing the junction when the next stage starts, increasing the likelihood of collisions.

This way the traffic is systematically moved through the intersection, there is always part of the intersection running on green in short phases, rather than the whole intersection going on pause. And the traffic is 'spat out” on the other side.

But it may well be time for more ‘tweaking'. Brookfield is now seven years old, the city is burgeoning and there's new pressure. 'We have all noticed new congestion there, so I am looking at changing the fixed times. Very soon.”

And when he retires Haydn will look back on Brookfield intersection with professional pride. 'Very much so.” He unraveled a nasty traffic snarl, saved the ratepayer much money, and the motorists time, agro and accidents.

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7 comments

Brookfield

Posted on 25-11-2016 12:54 | By waiknot

Brookfield is a nightmare, just make it a simple lights controled X Rd intersection.


Dodgy ...

Posted on 25-11-2016 13:51 | By chancer

Brookfield roundabout is now a dream, although visitors have problems 'cos they don't know where to enter so they can 'pop' out in the correct place only because they don't read the signs ahead of time. No more snarl ups, clenched teeth & fists. I know people who live very nearby and were vehemently against the lights as they wouldn't be able to get out of their driveway - well, they have all the time in world now but they won't admit it. Talk about head in the sand !!! Great job - thank you.


brookfield lights

Posted on 25-11-2016 13:51 | By susan

everyday i still see people going through red lights at brookfield,


Controlled to a standstill

Posted on 25-11-2016 15:03 | By sobeit

Tauranga's traffic control is designed (presumably by Haydn ?) to stop traffic. Other citys' traffic seems to flow albeit with longer stops but once you get going it flows. For most intersections the intersection is clear for as long as its occupied. Appalling waste of resource ? Remember the lady who did Maungatapu roundabout. Local pundits said it wouldn't work and that was about 10 years ago.Looks fine to me.Council should ring her up and get things sorted.Present system is designed for gridlock.


Hayden

Posted on 26-11-2016 08:59 | By Capt_Kaveman

You need to quit, the welcome bay and Brookfield iare 2 large jokes, then we have Hewletts road which because of your quick and unmanned phasing is a main cause of the build up at peak times, id like to know the crash stats for Brookfield OT Rd / Bellevue by the park, sorry just like your co worker Martin you both need to stand down


I avoid Brookfield if I can

Posted on 27-11-2016 11:51 | By Cydifor

Such a spaghetti junction simply getting my ducks in a row so that I end up in the right lane to exit the whole quagmire. I usually have to do another exit once out of the place simply to get where I am really going. Have to admit though that the tightness of the area has been juggled well. Now what is happening with the huge Maungatapu roundabout and the associated lights there.? I always seem to be snarled up in the far left lane getting around the very tight lane by Maungatapu Road. And what of the proposed 9th Ave and Chadwick Road traffic lights which are not wanted by anyone? Council can save money there as lights simply not wanted or needed in those areas.


Brookfield nightmare

Posted on 28-11-2016 11:57 | By DonQ

I can't leave this self-congratulatory article by an inept council go unchallenged.The only problem with the previous roundabout was at peaktime, when traffic turning from Bellevue Rd into Otumoetai Rd (west) (which was offset from the roundabout) would tail back into the roundabout and block it.One thing they did get right was integrating both sides of Otumoetai road into the roundabout. problem solved.But did they stop there? Oh no! This streets engineer had obviously been told to use as many traffic ights as as he could (council had got them on a bulk deal perhaps, in lots of 100?)The nett result was that ALL traffic is now halted for ridiculous amounts of time.The absurd thing is that traffic flowed smoothly in the week the new roundabout was opened, before they turned the damn lights on! Poor work.


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