Sunday, 28 February 2016
Sydney Metro NW: higher cost than CityRail if no branching (part 2)
The previous post established Sydney Metro NW will have very poor cost per pax metrics (even worse than Sydney Trains!). We now look at the case if Metro NW also connects an additional branch by taking over the (existing) North Shore rail line tracks between Gordon and Hornbsy as follows:
This will improve cost metrics as follows:
Saturday, 27 February 2016
Sydney Metro NW: higher cost than CityRail if no branching (part 1)
Branching of railway lines have a bad name from an engineering perspective (but often are a good thing from an economic perspective).
They can cause overcrowding (especially at inner urban stations) during peak hours, they can increase complexity and they can cause unreliability if they are on the surface (ie: if they are not in a tunnel or in an overpass).
They are also (wrongly) blamed for low frequencies (eg. every 15~30mins) during off peak periods. However, as we shall see below, in fact it is the high operating costs of unbranched lines that make high off peak frequencies uneconomic. As shown below, branching in this case **helps** improve off peak economics and is either neutral or positive for better off peak frequencies.
As for the issue of decreased reliability, this is so for surface ("flat junction") rail lines, where branches need to cross over the other rail line (of the bidirectional track pair). But the flat junction problems disappear completely when rail lines are in separate tunnels.
Without a doubt, Sydney's network has far too much branching, with each end often branching not just to two branches, but often into three or four branches. Clearly 3-4 branches are too much, but this does not necessarily mean a single branch point (into two branches) is bad. In fact, around the world, numerous modern rail systems use branching - typically to a moderate degree of one branch at one or both ends. Crossrail, RER, even Hong Kong's East Rail line all have branches.
So should Sydney Metro have branches? Previously, a case was made that Sydney Metro SW does not need a branch. Instead, by extending to Liverpool and then to Parramatta (via taking over the Cumberland line tracks), this would bring in enough patronage to fill up the 45,000 pax/hr capacity of Sydney Metro without branching.
On the other hand, Metro NW is a different story. There is massive spare capacity and the many "string of pearls" employment centres strung up at Chatswood, MacPark, Castle Hill, Norwest and Rouse will all serve to reduce & even out the peaky, unidirectional passenger flows seen in Metro SW. So for the foreseeable future to 2060 and beyond, capacity of 22,000 pax/hr will be the most that is ever needed.
Metro NW without a branch will also have very poor operating cost metrics. The CIE (Centre for International Economics) Report released by IPART in December 2015 shows that all the hype about Sydney Metro's low maintenance driverless trains (that get rid of drivers and get rid of train guards completely), is just that - hype. Benchmarks from around the world show that even the most "technically efficient" rail systems are only around 30% more efficient than Sydney Trains (in terms of cost of moving one carriage over one km). For example, Singapore's Metro has a cost of $7.55 (to move one train car for one km) vs Sydney Trains $9.13. Where the real inefficiencies lies is not lack of fancy train hardware or maintenance cost inefficiency, but in "allocative efficiency" - which is about patronage, rail catchments, service differentiation and demand side measures - ie: measures to ensure train carriages are kept full. Allocative efficiency (ie: cost per pax trip) is where Sydney Trains underperforms by 300%, as shown below:
The Singapore benchmark of $7.55 to move one train car along one km provides an excellent way to cost Sydney Metro NW's operating expenses:
They can cause overcrowding (especially at inner urban stations) during peak hours, they can increase complexity and they can cause unreliability if they are on the surface (ie: if they are not in a tunnel or in an overpass).
They are also (wrongly) blamed for low frequencies (eg. every 15~30mins) during off peak periods. However, as we shall see below, in fact it is the high operating costs of unbranched lines that make high off peak frequencies uneconomic. As shown below, branching in this case **helps** improve off peak economics and is either neutral or positive for better off peak frequencies.
As for the issue of decreased reliability, this is so for surface ("flat junction") rail lines, where branches need to cross over the other rail line (of the bidirectional track pair). But the flat junction problems disappear completely when rail lines are in separate tunnels.
Without a doubt, Sydney's network has far too much branching, with each end often branching not just to two branches, but often into three or four branches. Clearly 3-4 branches are too much, but this does not necessarily mean a single branch point (into two branches) is bad. In fact, around the world, numerous modern rail systems use branching - typically to a moderate degree of one branch at one or both ends. Crossrail, RER, even Hong Kong's East Rail line all have branches.
On the other hand, Metro NW is a different story. There is massive spare capacity and the many "string of pearls" employment centres strung up at Chatswood, MacPark, Castle Hill, Norwest and Rouse will all serve to reduce & even out the peaky, unidirectional passenger flows seen in Metro SW. So for the foreseeable future to 2060 and beyond, capacity of 22,000 pax/hr will be the most that is ever needed.
Metro NW without a branch will also have very poor operating cost metrics. The CIE (Centre for International Economics) Report released by IPART in December 2015 shows that all the hype about Sydney Metro's low maintenance driverless trains (that get rid of drivers and get rid of train guards completely), is just that - hype. Benchmarks from around the world show that even the most "technically efficient" rail systems are only around 30% more efficient than Sydney Trains (in terms of cost of moving one carriage over one km). For example, Singapore's Metro has a cost of $7.55 (to move one train car for one km) vs Sydney Trains $9.13. Where the real inefficiencies lies is not lack of fancy train hardware or maintenance cost inefficiency, but in "allocative efficiency" - which is about patronage, rail catchments, service differentiation and demand side measures - ie: measures to ensure train carriages are kept full. Allocative efficiency (ie: cost per pax trip) is where Sydney Trains underperforms by 300%, as shown below:
Tuesday, 2 February 2016
Sydney Metro: extension to Liverpool will untangle Western line
In December 2015, TfNSW confirmed it was considering an extension of Sydney Metro to Liverpool via a direct route that would pass through the vicinity of Bankstown airport. This announcement also marks the first (major) departure of Sydney Metro plans from the 2012 Transport Masterplan. However, most people would consider the Parramatta to CBD corridor to be higher in priority, so why is so much being poured into the Bankstown & Liverpool corridors and not the Parramatta/Western line corridor?
As it turns out, the Liverpool extension would not only speed up Liverpool to CBD journeys, but it can also untangle the Western line and create a 200% capacity increment, which should be enough for a Sydney of 10+ million people. Plus it would also provide a Cumberland line "on steroids", that would have trains running every 2 minutes instead of the current every 15-30 minutes. The diagram below shows an example of how the Western line "untangling" would work:
As it turns out, the Liverpool extension would not only speed up Liverpool to CBD journeys, but it can also untangle the Western line and create a 200% capacity increment, which should be enough for a Sydney of 10+ million people. Plus it would also provide a Cumberland line "on steroids", that would have trains running every 2 minutes instead of the current every 15-30 minutes. The diagram below shows an example of how the Western line "untangling" would work:
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