brixtonite wrote:
I wonder:

Have they got a convincing explanation of how they're going to do this
without getting fouled up in traffic?

Basically, near-absolute priority along the whole route. I don't think
that any section will be shared-use with general traffic at all (much of
it uses existing bus priority routes). AIUI, the only junctions where
the tram will not have priority are Holborn (heavy east-west bus
traffic) and Euston (heavy east-west car traffic). AIUI there are (or at
least were) plans to turn Camden High Street into a public transport
"boulevard", with two-way operation for buses, trams, cycles, possibly
taxis and access only for private vehicles (other private traffic would
be routed via the parallel Camden Street).

At Euston Road in particular, northbound departures from Tavistock
Square and southbound departures from Euston will be managed carefully
to fit in with the cycle time of the lights at the crossroads. I'm not
sure what the cycle time is, but if it were 60 seconds, then trams would
need to hit every other cycle quite reliably to maintain the two-minute
frequency through the core section. This is why I'm somewhat surprised
that the alternative routing to King's Cross via Judd Street did not
last longer in the planning stages.

Why does the King's Cross branch go the wrong way?

Why does the Brixton branch go via Lambeth North rather than Elephant?


The King's Cross branch arrives from the North in order not to foul up
the Euston Road. IIRC the plans say that the crossing at Euston will
be the only place where trams won't have absolute priority over
traffic, because it would cause mayhem.

The original plan was to have the King's Cross branch running through
Somers Town via Brill Place, which would have been a quick route with
minimal traffic disruption - but the local residents were strongly
against it and so the Mornington Crescent branch was born.

Another option considered early on but discarded (not sure why) was from
Tavistock Square via Tavistock Place and Judd Street into Midland Road.

Incidentally, the Mornington Crescent route is not finalised - LB Camden
would still like to see it routed along Euston Road as this is more
direct, but the practicalities are difficult - although bus lanes
already exist along that bit of road, the bus frequency is quite high
(seven routes including the very-high-frequency 73) and I'm not sure
that those lanes have the capacity to reliably carry 15tph plus some
30-40bph (at a guess).

As for the Brixton branch, perhaps it will fit in better with the
remodelling of the elephant if this branch doesn't go that way. Or
perhaps it's just because via Lambeth North is the natural route that
the buses to Brixton take at the moment.

The remodelling of the Elephant is still fairly up in the air, so it
wouldn't be difficult to incorporate the Brixton branch. However, as you
say, the Lambeth North route is already a natural bus route and I
believe it is higher-demand than Kennington Park Road (the 59/159 are
quite heavily used). Sending the Brixton branch via Elephant was an
option until quite recently.

I wondered why they run via Stockwell rather than Brixton Road, though
- is it just because interchange with the Northern line would be less
convenient at Oval, or is there another reason?

Not sure about this. Could be related to interchange at Stockwell, as
you mention (CRT may feed the Northern line and Oval might not have the
capacity for this); the capacity of bus priority along Brixton Road; or
even the ability to provide more capacity relief to the Northern and (to
a lesser extent) Victoria lines.


--
Dave Arquati
www.alwaystouchout.com - Transport projects in London