The government argues that cross-city traffic is so critical that the they want to (without a mandate) spend $8 billion building just the first phase of the East-West tunnel.
If that’s the case, then why does the newly remodelled (2008-2010) M1 corridor only provide two lanes in each direction for those cross-city trips?
Eastbound (coming off the Westgate bridge, towards the Burnley tunnel):
Westbound (coming out of the Domain tunnel, towards the Westgate Bridge):
…and another westbound view from a bit further on, where the lanes merge down to two:
These pictures are all from Google Streetview, and actually show the freeway towards the end of the modifications… I’ve checked, and this is how it is today.
Road designers aren’t idiots. When they do massive remodelling like this to re-organise the lanes, they look at traffic flows. The Westgate bridge is now 5 lanes in each direction, and the Citylink tunnels are 3 each, but there are only 2 through lanes each way.
That leaves the conclusion that the traffic going from the east to the west and vice-versa is only a small proportion of the total traffic, particularly compared to numbers going over the Westgate.
Update Tuesday: I’ve had some feedback on this post (not via comments) to the effect that some thing this is twisting the truth, because various lanes leave and join the motorway along its length, so the total number of lanes at any one point is always more than 2. That’s true, but my point is that (particularly in congested conditions), the capacity of the M1 for east to west cross-city traffic is heavily influenced by the number of lanes that go all the way through… and this is only two lanes each way.
One person also pointed out an additional lane is available westbound via the Todd Road exit and the service station… but I would think it’s unlikely many drivers going from the east to the west would use this — plus I think it involves a merge with traffic from Kingsway and another from the Bolte Bridge southbound.