Stephen Rees's blog

Thoughts about the relationships between transport and the urban area it serves

Archive for November 20th, 2006

Heart and soul of the city | Conservation | Guardian Unlimited Environment

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Heart and soul of the city | Conservation | Guardian Unlimited Environment

The demolition of a vast motorway through the centre of South Korea’s capital and the restoration of a river and park in its place proves that mega-cities can be changed for the better.

I missed this the first time around, so I am grateful to Babara Docherty for posting it to the Livable Region Coalition list.

It’s not often you get post graduate transportation economics in a daily paper but this is really important

Braess’s paradox, named after mathematician Dietrich Braess, gives the lie to governments and local authorities that argue that building more roads reduces congestion.

According to Wikipedia, the online encyclopaedia, it works like this: “For each point of a road network, let there be given the number of cars starting from it, and the destination of the cars. Under these conditions, one wishes to estimate the distribution of traffic flow. Whether one street is preferable to another depends not only on the quality of the road but also on the density of the flow. If every driver takes the path that looks most favourable to him, the resultant running times need not be minimal. Furthermore, it is indicated by an example that an extension of the road network may cause a redistribution of the traffic that results in longer individual running times.”

The article talks about a number of other Asian cities that have done this, but we should all be familiar with the removal of inner city freeways in Toronto and San Francisco which had precisely this effect. This is not just theory – there are many examples that have been extensively reported – so many in fact that Phil Goodwin and others produced a study of studies.

This by the way is not new. Here is a citation which Braess himself gives

J.G. Wardrop, Some theoretical aspects of road traffic Research in Proc. of the Inst. of Civil Engineers, Part II, 325-378 (1952)

So we have known for over fifty years that building new roads generates traffic and taking roads out of the network does not increase congestion it actually reduces it. But somehow that message has still to get through to the BC Ministry of covering the world’s best place in concrete.

Written by Stephen Rees

November 20, 2006 at 5:34 pm

Van City Water Still Not Safe :: thetyee.ca

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Van City Water Still Not Safe :: thetyee.ca

The boil water advisory was lifted for Richmond and other suburbs quite quickly, but that doesn’t mean our water is clean – far from it. I have been doing some refurbishment on our washroom, and the toilet cistern was full of sludge, which had accumulated over the years. Since the water here is somewhat acidic, rubber fittings like washers and flap valves rot, and there were also pin holes in the stainless steel feed pipe.

We use a Waterpik filter on our kitchen tap, for drinking and filling the kettle mainly to reduce the amount of black stuff the builds up on the element. It also removes the smell and taste of chlorine. In an excess of caution I bought a new filter on Saturday of the type that also takes out cysts and sediments. It was full of crud and useless two days later!

There will be a GVRD filtration plant in a few years time, but officials are already saying that it will not be able to cope with the volume of muck we’ve got in the water at the moment. (UPDATE Nov 23 : Although more recently that story changed). We also get regular doses of “tea leaf scale” which is rust from the inside of the pipes en route to us. The City comes and flushes the pipes by turning on the fire hydrant outside our front door fairly shortly after each complaint that I have made. No-one else seems to bother.

The strange thing in all this is that people here (and in Portland and Seattle) boast about their water – and turn their noses up at London’s water which, they say, has been through five people before you drink it. But that water is treated, and looks and tastes a lot better than the stuff here and I don’t mean now, I mean normally. I never felt the need to filter water in Britain – though with this essential service now privatised I might consider it.

When we lived in Victoria (which also has untreated water) there was a scare about cryptosporidium. Apparently caused by dead cats in the water intake of the Humpback reservoir. So much for “pristine watersheds” where no-one is allowed to go. Presumably if the water shed was open, someone might notice the dead cats. In Britain, sailing on reservoirs and picnicing next to them is common. Once again, I never heard of parasites in the water there.

I don’t think it’s about cleanliness at all. I think it is just a way to avoid paying more for water – and, in the case of Victoria, notoriouly, sewage treatment too.

Written by Stephen Rees

November 20, 2006 at 2:18 pm