Tuesday, September 27, 2011

Crowd = 200,000! Who's counting?

There's been a lot of guesstimating going on about exactly how many people descended on Auckland's waterfront that fateful Friday opening of the RWC when it all turned to custard and the blame game set in. There's been numbers up to 200,000 bandied about, almost as a justification of success. The independent report by lawyer Chris Moore appears to assume this guesstimate for his assessment. Garbage in - garbage out....

I did some basic work using the Council's GIS system to analyse the crowd carrying capacity of central Auckland waterfront spaces around Queens Wharf that did get crowded. You can see the area I looked at in these five graphics. Separate area calculations can easily be done using Council GIS tools. For example the total area of Queens Wharf - excluding the ferry terminal - is 25,500 square metres.

I know not all of that area can be used to hold people, but the lion's share of it can, some in Shed 10, the Cloud and other open areas. And it's fenced to the waterfront edge so you can cram them in a bit - without worrying about someone falling into the water.

That Friday, the biggest squeeze as far as I understand was on Quay Street. People on Queens Wharf were restricted, but they were not on Quay Street. On this map here's a big chunk of Quay Street that was set aside for pedestrians. The total area of this chunk is 16,600 square metres. On that Friday it was more crowded than Queens Wharf. Sure. But not over the whole area, and it's quite a lot smaller in size, and it didn't have fences to stop people falling into the water...

I've added in here the bit of Wharf that sticks out into the Viaduct - not all the way into Te Whero and I know that would add some more. But I didn't have all day. This bit of the Viaduct adds 7,200 square metres of crowd handling capacity.

I also added in the whole of QE II Square outside Britomart. Not really fair - because that part outside the shops wasn't that popular with people. But I've added it all in. That adds a further 6,600 square metres of crowd handling capacity.

Princes Wharf is a joke when it comes to public space as we all know. And it's going to become an even worse joke if the council has it's way and flogs off the bit of it that does serve the cruise ship industry (See NZ Herald Business Section again Tuesday). Anyway the little bit of edge that is available for public use amounts to another 6,500 square metres of public space. Again - no fence to stop people falling into the water - so people keep back from the edge and don't get closely crowded. (By the way, a mate of mine who had the sense to go there to watch the fireworks said it was easy-peasy - hardly anyone there - and after the fireworks he walked easily down to the end of the wharf, across Quay Street, up Albert Street, left into Custom House Quay (which was almost empty he told me - no crowds in that part of town), and got home quick. So he by-passed the crowds in the central parts of Quay Street where people had gathered to watch the fireworks.)

This brings me to Captain Cook Wharf. It wasn't available that Friday, so couldn't be used, but I have it here for interest. The area of it - plus a bit of the waterfront that Port uses - you can see on this map - has a total area of 20,800 square metres.

Ok. Back to Friday. If you add up these waterfront areas - excluding Captain Cook - you get a total of 62,400 square metres of public waterfront space.

If you assume that the 12,000 maximum figure used for Queens Wharf is a "safe waterfront crowd" density, then assuming that was applied across all of the available waterfront space that Friday night, you would actually be able to accommodate a maximum of 29,400 people on Auckland's waterfront.

Less than 30,000.

A bit different from the figures being bandied about.

But I know that parts of Quay Street got a lot more crowded than Queens Wharf. So I did a bit more reading. There's all sorts of interesting stuff on the Internet about crowd safety.

...At occupancies of about 7 persons per square meter the crowd becomes almost a fluid mass. Shock waves can be propagated through the mass sufficient to lift people off of their feet and propel them distances of 3 m (10 ft) or more. People may be literally lifted out of their shoes, and have clothing torn off. Intense crowd pressures, exacerbated by anxiety, make it difficult to breathe. The heat and thermal insulation of surrounding bodies cause some to be weakened and faint. Access to those who fall is impossible. Removal of those in distress can only be accomplished by lifting them up and passing them overhead to the exterior of the crowd....

Don't think we had anything like that - though at various pinch points - and we are quite good at pinch points - like at the ends of the big screen in Quay Street - there was a pretty tight squeeze. And particularly within 100 metres of the entrance to Queens Wharf. It was the crowd density around the Queens Wharf entrance that forced the closures of Britomart Station and the Ferry Terminal because people couldn't get in or out effectively because of the Queens Wharf/Fireworks queue.

Reading on: "In the Guides the safety limit for crowd density is defined as 40 people in 10 square metres for a moving crowd and 47 for standing areas...." and "...Between 3 and 5 people per square metre are typical of the normal ingress density...."

So let's look at that Friday again. My obervation of Friday was that Queens Wharf wasn't full. I was on it and I don't think it was full. The people counters didn't know what they were doing and they shut the gates early. I reckon there was 9,000 on Queens Wharf, but let's say - for the argument - there were 12,000 there. Princes Wharf was almost empty - but let's say it was equal to the allowable crowd density of Queens Wharf on average, and let's say the average crowd density of QE II Square and the Viaduct Wharf extension was that as well - basically because that's where people didn't really want to be. They were pushing into Quay Street to get to Queens Wharf, or to a place they could see the fireworks, or to where they could see a big screen that was working. That gives a total of 21,500 people everywhere on the Waterfront (the places I'm talking about here: Queens Wharf, Princes Wharf, Viaduct wharf extension, QE II Square) but excluding Quay Street.

Assuming the whole of Quay Street was crowded on average at 4 people/square metre - which is the safety limit for a standing crowd - according to "the guidelines".

At 4 people/square metre (maximum safe crowd), the whole of the Quay Street section shown in the maps above would have held 66,400 people.

These numbers suggest the crowd on the waterfront spaces shown in these maps was 87,900 on Friday. However I think that is an over-estimate - because it wasn't that crowded over the whole length of Quay Street. The scrums were by the big screen and at the Queens Wharf entrance. More like 50,000 to 75,000 I would assess at the outside.

Makes you think - doesn't it. Shows how little public space Auckland has in Auckland's CBD waterfront. Shows how valuable public space on the waterfront Queens Wharf really is. Puts it into proportion and into perspective.

1 comment:

  1. I was right in the middle of the crowd in QE 2 square and it was surely only the numbers you have mentioned.....

    More importantly it was great fun....and all well behaved from our experience.....trains were not available so we got a Taxi???? at half time??

    Go Figure

    Adam

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