Hoisted from comments:

In my post on the Wood Green regeneration plan, I said: “There should be no private motor vehicles on Green Lanes between Wood Green and Turnpike Lane… Traffic along Hornsey Park Road and other N-S routes should be filtered, to eliminate through traffic”. In reply, Joe asks:

Is this practical? Can it be generalised to all London’s radial routes? Haringey is a buffer between Central London to the south and lots of people to the north who want to go there, so there is always going to be some through-traffic – it needs to be reduced but could never be eliminated? If so then I think a better solution might be to fully protect or filter all the minor roads, residential streets, even B-roads, thus forcing all through-traffic onto the A-roads. Some traffic will evaporate and the residual A-road flow would be easily measurable and easier to manage (with congestion charging or other methods as appropriate).

Good question. We agree on B-roads & on filters: the hierarchy of provision – arterial, distributor, local – should mean something. And, no, you can’t do what I’m proposing to all radial routes. There are two reasons to do it in Wood Green, though.

One is that Green Lanes (both in Wood Green and further south) is too narrow to have continuous two-way bus lanes, so if you want good quality high volume bus service you need to restrict other traffic. Take your choice, but you simply can’t have both.

If Green Lanes between Wood Green and Turnpike Lane were bus-only, buses would move faster(*) there; if no cars are allowed to pass though Wood Green by any route, there should also be reduced traffic on Green Lanes through Harringay and Manor House, and if so buses would move faster there, too. This would produce some modal shift from cars to buses. Whether the reduction in traffic on Green Lanes south of Turnpike would be sufficient to allow the buses there to flow, we would have to see. There are, however, further possibilities for reducing Green Lanes congestion by filtering some other neighbouring areas, discussed here.

On some other radial roads in North London – in particular, the A10/Seven Sisters system, and Holloway Road/A1 – the roadway is generally wide enough that bus lanes could be accommodated in both directions, while still allowing through traffic of private cars. Sadly, those bus lanes are often sacrificed to parking, loading, or wide pavements – see my 1st March post on Bruce Grove.

The second reason for doing this in Wood Green is the proposed regeneration. The plan put out for consultation claims it can achieve both higher density and an improved pedestrian / cycling environment without reducing car traffic, but that’s just fantasy in the face of the laws of geometry. You could answer that the regeneration shouldn’t take place, in which case I’d still say that the case for cutting through traffic is good, for the reasons given above. But if anything is done to increase the density of Wood Green, or if we aspire to actually create streets-for-people there (or, as the regeneration plan proposes, both), then we can’t have a highway (much less two highways) running through it.

(*) (Note: when I say I want faster bus service, I am conscious of the need to keep buses from moving too fast; as Tom Kearney has learned at great cost to himself and has subsequently taught the rest of us, bus drivers are incentivised to speed, often at the expense of safety. I would like them to be able to achieve the 20mph limit, however.)