Earl Purple wrote:
Dave Arquati wrote:

I was talking about the effect on people who lived in the residential
area through which the Westway was constructed.

I don't know about then but taking Portobello Road as an example (the
Westway runs close). Has it had a negative effect on that road or will
the extended CG zone have a worse effect?

Well, 600 homes were demolished to build the Westway, and their
surviving neighbours in some places were as close to the motorway as 7
metres. North Kensington suffered extensive blight, pollution and
disruption during construction - all in an already-deprived area. Prices
for those properties closest to the Westway are still depressed as those
properties still experience noise, visual and atmospheric pollution.

In addition, despite the motorway being elevated, some 20 acres of land
were left derelict (although use has now been found for a proportion of
that). Severance was (and is) a significant issue in some locations,
particularly Latimer Road which was cut in half by the junction for the
West Cross Route.

The effect of the extended congestion charging zone is anyone's guess -
but it should reduce pollution in the area. In a borough where 50% of
the population have no access to a car and almost three times as many
people travel to work by public transport as by car, the positive effect
of the congestion charge extension (an improvement in bus services) is
likely to be significant. Those figures refer to the whole of Kensington
& Chelsea - car ownership in North Kensington is likely to be
significantly lower.

Yes. That's not really a point up for debate - research is available all
over the place proving that new roads generate significant levels of new
traffic. I doubt that someone coming from Portsmouth heading north would
divert from the M25 via inner west London, although M25 congestion might
force them to do so - which would be extremely bad for the residents of
West London, who would then have to put up with long-distance traffic
passing through their area (the motorway may be segregated, but the
pollution and noise wouldn't be).


Now what journey would you now make in a car on the M25 that you could
otherwise make on public transport? There is a railway line on the
"West Cross Route" that goes from Clapham through Kensington up to
Willesden, and there's another line that goes to Harrow. Now if they
improved the service on those lines and made them better known (they
don't appear on underground maps) then more people might consider using
them.


I'm not sure I really understand what point you are making in reference
to my point that new roads generate new traffic. Public transport
alternatives are somewhat irrelevant here; the point is that the M25 has
encouraged people to make journeys (by car) they wouldn't have
considered making (by any mode) before the M25 was constructed.

The obvious example of traffic generation is the M25. Many people make
more journeys by car specifically because the M25 is there - it has
encouraged a vast number of orbital commutes which never existed before
it was built. An urban motorway, similarly, would encourage people to
make a car-based commute (or other journey) across inner London where
they wouldn't have done so before.

And before the M25 was built, there was much higher unemployment.

The M25 *may* have had a positive effect upon unemployment but that
statement is rather disconnected. Unemployment levels are subject to a
wide range of economic factors; it's extremely likely that the M25 was
constructed in response to increasing employment levels and increasing
economic activity, rather than the other way around.

And
part of this is also caused by house prices continuing to rise thus
forcing people to live further away from their place of work and make a
longer commute. People move jobs far more frequently than they used to
and can't always find a job close to home (much that we'd like to). New
industrial estates open just off these motorways because they are now
easier to get to, and land is cheaper there.

People travel further to reach jobs partly because they can, and partly
because those jobs move further away as a result of new road
construction. The benefits of new road construction aren't always that
clear-cut, as the road will generally alter the way employment is
distributed anyway (e.g. centralisation). That has both positive and
negative aspects.

As a result, many businesses have moved out to these business parks,
they have a lot of car-parking and very poor public transport
facilities. Car-pooling would be ideal but impractical if people don't
actually start and finish work at exactly the same time each day.
However it may certainly be the way to go.

Yes, perhaps. We now have these sites which are poorly accessible by
public transport and hard to serve with it, so some way must be found to
make the use of the car to access them more efficient. However, we can
avoid repeating the mistake by stopping extensive new road construction
and holding back construction in areas only accessible by car. The M25
has encouraged a wide pattern of orbital car commuting across the South
East which is virtually impossible to cater for attractively with public
transport. Any new urban motorways in London will similarly encourage
new car-based orbital commuting around London for which it will be very
difficult to provide an attractive public transport competitor.

Limited funds are available, and railway and motorway projects are both
extremely expensive. It's one or the other, and the project which
increases car journeys significantly is not likely to win. "They" should
definitely improve railway (and other public transport) connections -
but they shouldn't start building urban motorways.

But roads are not just limited to cars - buses and lorries also use
them. Railways are not so environmentally friendly either, as you need
electrification and normally that means overhead cables. You need far
more land. Crossing them is much harder, and generally they can take
you only to one place.

The environmental friendliness of railways versus motorways has been
debated many times before in this group and elsewhere. I totally
disagree with your other points. Railways do not need far more land -
they use far less! I'm not sure why crossing them is "much harder" -
railways are narrower than motorways, so bridges are likely to be
cheaper. The only railway that takes you to one place is a shuttle
service between two stations with no onward connections at either end.
Crossrail will have connections to 9 different Underground lines, a wide
variety of other railway services and a huge number of local bus
services. If you're considering access to and from the motorway, you
have to consider access to and from the railway too.

Either way, it's very expensive, with new road costs now in the many
millions of pounds per kilometre.


Good investment though. It cost a lot of money to build the GWR too,
but now as a result we have it.

I don't think it's particularly good to invest in infrastructure which
will lead to an increase in traffic, a rise in pollution levels, blight
upon homes and an increased reliance on the private car which then leads
to an increasing gap in mobility levels between those who can and cannot
run a car, and to an increased dependence of our economy upon oil.

Firstly, since a new road will generate new traffic that surrounding
roads will have to absorb, a new road project is only likely to cut
traffic queues on certain parts of the network for a certain number of
years before the situation worsens again (see the M25 and associated
widening projects).

If the road is good then there'll be no need for rat-running. But it
may generate more business in the area (as it will be easier to get
access) so more business will open, more superstores, etc, and you may
get people leaving the main road to use the facilities.

And therein lies the problem. No road is an island... traffic from
motorways never starts or finishes on motorways, it has to perform those
parts of the trips on the local road network. Since a new motorway will
lead to a rise in traffic, even though congestion on the roads it
relieves will fall initially, there will be a gradual and sustained rise
in the levels of traffic on all other nearby roads.

Secondly, when factoring in revenue lost through congestion, it's time
to start factoring in the increased cost of pollution-related illness
and disbenefits and road accidents, as well as the less-easily
quantifiable social exclusion and general environmental effects.

But the optimal speed for reducing pollution is 56mph. Going through
urban streets at an average of 12mph stop/start is thus very much more
polluting.

I agree that stop-start driving is quite polluting - but since the new
motorway will lead to an increase in traffic on a whole number of roads
used to access it, then any saving made from having a freer-flowing
through route is eroded by increased congestion on the access roads.

Incidentally, I remain unconvinced that free-flowing traffic at 56mph
causes less pollution than free-flowing traffic at a lower speed. Isn't
it just that 56mph is a point beyond which the increases in fuel
consumption and therefore pollution rise much faster than the increase
in speed? (i.e. below 56mph, assuming free-flowing traffic, the
relationship is fairly linear)

Other people are debating the truth in that, but, as always, junctions
often limit capacity on a network, and urban motorways will have plenty
of those. In addition, although a smaller point, it's worth noting that
the road capacity as described is only available to those with access to
a car, whereas rail capacity is (theoretically) available to all.

But if they also ran buses on those routes that would also be available
to all.

Hardly. How many buses run on the Westway and the West Cross Route? Some
long-distance coach services use them, but these are of no benefit to
the local areas the urban motorway is meant to serve - and any local bus
service using an urban motorway bypasses most of the population it
should be serving.

The congestion charge raises money to fund public transport
improvements, not the roads.

which seems to be more silly bus routes, carrying 8 passengers or so,
going down narrow roads totally inappropriate for a bus, stopping
everytime something comes the other way, still very poor service come
6-7pm (when many are still commuting home from work).

Really? I've found the improvement in bus services very pleasing, with a
higher frequency of buses available, more night services available and
more direct journey opportunities - all of which made me even less
likely to get a car than I already was.

I'd rather see more express bus routes, infrequent stops, going along A
roads, particularly primary ones (generally more orbital).

I agree that express bus routes (particularly orbital ones) are a good
idea, but in order to provide a decent service, they have to penetrate
town centres and serve useful locations, rather than the side of a dual
carriageway.

Nope... but I lived next to a motorway for 18 years, and I wouldn't wish
it upon anyone. I live in the west of London (which already has urban
motorways, one of which is extremely close to my home), but I don't
drive (and neither do a large number of people in this are) - and
therefore I get a rather disproportionate share of the disbenefits of
urban motorways compared to the benefits.

I live close to the end of the M1 and close to where the A406 meets the
A1 and the A41 is also close by so I am surrounded by primary dual
carriageways. That actually makes car travel fairly convenient (while
the Northern Line is useful only if you want to go to Central London or
to Edgware). Most of the residents would prefer to see the old plans of
the A406 tunnel go ahead. I think it would be satisfactory simply to
have the A406 connect at both ends of the A1 via a tunnel without any
other tunnel links at all - it would at least reduce a vast amount of
the traffic at that junction.

Perhaps. But whilst providing the tunnel under Henleys Corner may
improve the situation there, it will also just move the problem down the
road to the next limiting junction, as traffic along the A406 will
increase to fill the new capacity provided by the improvement works at
Henleys Corner. It's all a rather vicious circle, and it seems like the
only way to lock in the benefits of a scheme like the one you mention is
to charge people to use the road to stop new traffic using up the new
capacity.

I worked as a minicab driver for about 18 months between July 2002 and
the end of 2003.

OK...?

--
Dave Arquati
Imperial College, SW7
www.alwaystouchout.com - Transport projects in London