[sustran] Bus Lanes

[Kerry Wood]

Dear Kisan

Your e-mail to Paul sounds a bit discouraged: maybe some of these points
will help:

Cars use space much less efficiently (passengers per lane per hour) than
buses, so more cars can only make congestion worse. A 7 - 8% growth rate
will very quickly be a problem.

Safe pedestrian space may be even more important than bus lanes, and
cycles may also need priority.

The objective is not bus lanes, it is minimising congestion delays to
public transport. A suggested target is 95% of services within 5 minutes
of time.

The maximum number of buses in a bus lane is ideally about 60 per hour
one-way. You can get more (up to about 30 000 passengers / hour
according to Gardner--ICE Transport 8/92), but you then have to look out
for two problems:

-    Congestion at stops. Use a second lane for the stop, long enough to
hold the maximum number of buses likely to be in it at any one time, adn
with space for buses to turn into and out of the stop lane.

-    Congestion at junctions. You need enough time in a traffic signal
cycle to get both buses and other traffic through. A second streaming
lane for buses is a help.

If there are too many buses reallocating them onto different routes may
help, or use a two lane bus lane, or articulated buses.

Light rail is the next stage: it may be more affordable if you make
maximum use of local resources and refurbished second hand vehicles.
Suburban rail will probably be cheaper if route capacity is available
and it runs in the right direction.

Bus lanes don't have to be next to the left hand kerb (right kerb in
most places outside the Commonwealth). They can go in the centre lanes
(this needs extra space for passenger areas at stops, and  care with
getting passengers out to the stops), on the right lane of a one-way
street (still needs extra passenger space), or in a contraflow lane in a
one-way street. Of course, changing the position of a bus lane needs
care too, and perfect answers are unlikely.

Bicycles can share a bus lane if the minimum width is around 4.2 m (more
on bends, and maybe more for pedicabs).

Cars can be kept out of bus lanes. Methods include a kerb 120 mm high
(low enough for emergency vehicles to bump over it when needed), a 'bus
gate' at the entrance to the bus lane, or giving the drivers cameras so
that they can record offences for prosecution. However, cars need to be
able to access side turnings (but not neccessarily at peak hours). This
comes back to the position of the bus lane.

Traffic signal priority fits well with bus lanes, making them much more
effective. A token 5 second phase extension if a bus is coming is
useless: buses need to usually go straight through.

If a short section of road is too narrow for separate bus lanes, the
solution may be to use traffic signals to control entry to a flow that
will minimise congestion, with a bus lane on the approach to the traffic
signals. Buses can then bypass the queue and enter a reasonably
free-flowing general traffic stream through the bottleneck.

Parallel improvement areas are timekeeping, connections (good
connections need excellent timekeeping, or very frequent services) and
the buses themselves. If passenger transport is to be really effective
it needs to be faster than driving, so that it is still competitive
after allowing for access and transfer times, and parking time for cars.

You ask Paul, 'do bus lanes work?' and they may not work if enforcement
(active and passive) is bad and general traffic simply takes over.

I have not been in Mumbai for 25 years, but the little I remember is not
encouraging. The decision makers will inevitably want to ride around in
cars, but they must be made to understand that giving priority to
passenger transport (not necessarily on-road) will help the decision
makers personally, and everybody else just incidentally. (unless the
decision makers could be persuaded to use special buses, segregated by
high fares?) A rational approach might be very high car taxes, to both
control numbers and fund alternatives, but the political will for such a
policy is hard to find. Certainly we have not found it in New Zealand.

Best wishes with your search.

>

--
Kerry Wood  MICE  MIPENZ  MCIT
Transport Consultant
1 McFarlane Street, Wellington 6001, New Zealand
Phone + 64  4  971 5549