[sustran] Re: Article in Guardian Newspaper

[Robert Murray-Leach]

Hi Jack,

while I wouldn't fault your figures on current bus-occupancy in the US, 
isn't the point that if you achieved a modal shift from cars to buses that 
the occupancy rate of the buses would be much higher than the 11 per bus? 
If you have a rate of 2550 people per hour along a road, and they all chose 
to use buses, then you could expect occupancy rates of 20 per bus, and 
would only need 128 buses per hour. Rather than comparing apples with 
apples (ie. a system where car is the predominant mode of transport vs. a 
system where buses are the predominant mode of transport) you're comparing 
a car-predominant system with a bus-predominant system where user behavior 
is still defined as in a car-predominant system.

In relation to your web-site, I was interested to note in the paper 
entitled "the only solution to congestion"that while there were some facts 
about situations in which light rail was not suitable, there was no mention 
of any of the potential negative impacts of cars, and no attempt to balance 
the cost-benefits of mass transit vs. cars. The concluding statement 
therefore seemed largely unqualified, and also neglected to note that 
increased congestion actually lowered several emission types, such as NOX.
"The bottom line is obvious: If we really want to avoid far longer 
commuting times, average freeway speeds less than 20 mph, increased 
pollution and the endless urban sprawl generated by the escapees from such 
mass immobility; we can and we must build adequate new and expanded roads 
and freeways. There simply is no rational alternative."

Rob Murray-Leach



At 09:15 AM 29/03/03 -0800, you wrote:
>At 05:47 AM 3/29/03, Debi Goenka wrote:
>
>>
>>We are trying to get some buslanes in Mumbai, and I would like to get 
>>some answers. The standard response to bus lanes in Mumbai is that the 
>>existing roads are not wide enough - my answer is that in such cases, 
>>perhaps such roads should be reserved exclusively for buses!
>
>JM: Well, maybe so, maybe not, but that should be based on comparison of 
>how many persons per day the bus system would carry vs for the 
>corresponding roadway. And that is exactly the same kind of calculation I 
>was illustrating for light rail.
>
>To compare bus vs automobile in the same way compute
>PPHbus = BPD x BAVO
>PPHauto = APD x AAVO
>where BPH = buses per hour past an average point along the busway
>       APH = Autos per hour past an average point along the road
>       BAVO = Average Vehicle Occupancy of a bus, persons/bus
>       AAVO = Average Vehicle Occupancy of an auto,persons/auto.
>The mode providing the higher PPH count is more productive.
>
>For example, using typical US numbers, if the roadway lane were to carry 
>1700 vehicle/hour at an average vehicle occupancy of 1.5 persons/vehicle, 
>the roadway would be carrying 2550 persons/hour. In the alternative, if 
>the average bus occupancy were 11 persons/bus, you would have to run 231 
>buses per hour, or one every 15 seconds to provide equivalent transport 
>volume, 2550 persons/hour.
>
>All the above numbers are typical for US, except for the 231 buses per 
>hour which is very high. You should make this calculation for your own 
>numbers for Mumbai. But for typical US numbers, it seems very unlikely 
>that a lane could be more productively used as a busway than as a regular 
>freeway or expressway lane.
>
>Jack
><http://www.urbantransport.org/>www.urbantransport.org
>

Robert Murray-Leach
Green Transport Officer
The Conservation Council of South Australia
120 Wakefield St
Adelaide SA 5000
Tel.  (08) 8223 5155
Fax. (08) 8232 4782
E-mail. smogs at ccsa.asn.au