Metrolink - Alternative Routes - See post one for restrictions.

The concept is pretty straight forward, for the cost of one (extra) Metro line, you could afford about 5 or 6 Luas lines. Which obviously gives far greater coverage of the whole city then one extra Metro line would.

To be honest, I can’t really think of any alignment for a second line that would come even close to the Metrolink line in demand levels or passing a CBA. Maybe an East - West line, but that would overlap with Dart Underground.

Lucan certainly doesn’t need a Metro given it will be getting a DART+ line!

I mentioned this over on another thread. It seems the TII are suggesting using Luas/LRT rolling stock for the “Metro West” alignment rather then “Metrolink” rolling stock.

While I’ve no doubt this will be a popular alignment, I really don’t see the level of demand to justify Metrolink rolling stock operating every 90 seconds or anything even close to that!

Using LRT has become the norm for such orbital routes around Europe. Copenhagen is just about to open an orbital route that looks almost exactly the same as “Metro West”, it is about the same distance from the city, etc. and they are using Luas like trams for it. Paris also uses Luas like trams for their orbital routes.

I’m totally open to the idea of it being a “Metro”, but I’d love to see a detailed study into the alignment, what is the expected demand level, more or less then the Green line? What is the cost difference of using Luas on the alignment versus Metro?

BTW there is an interesting question here about the operating cost of driver operated Luas versus driverless Metro (but higher capital cost).

The issue most likely is that last 8%, you would likely need to tunnel that last 8% (possibly multiple short tunnels along the route), if you want to run a fully segregated, fully automated Metro.

You would add billions to the project.

That is why Copenhagen and Paris choose trams for their orbital routes. They mostly run like a Metro on fully segregated sections, but for the last 10% or so where they have to get into a very built up area, they run at street level, thus saving the cost of having to tunnel through those areas.

I do think it is a smart trade off.

Of course if the demand is there in future, nothing stopping you converting it to Metro.

Exactly this.

I've come around to the idea that these sort of hybrid tram/Metro systems can be a very useful tool in some circumstances.

Basically run like a Metro through areas of high segregation, mostly fields, at higher speeds and then when you come to major towns/urban areas where people actually want to go, you switch to street or near street running, so that you can get the tram into the heart of the area where people actually want to go.

If you aren't happy with the above, then your alternative options are:

• Tunnel under those urban areas to get to the heart of where people want to go. Obviously that massively increases the cost of the project, reasonable for a core city center like Dublin, but you would probably struggle to justify it for somewhere like Clondalkin!
• As Kris says, build the station outside the urban area, so outside the area people actually want to go too! Either leaves people having a long walk or a connecting bus.

The Danes seem to take this approach a lot and it seems to work very well for them. Not just for Copenhagen's orbital route, but they also in other cities they have some commuter towns connected to the nearby city by tram. The Tram gets up to 100km/h while running through fields between the two, but once it reaches the town it runs on the street to get into the town center.

Worth noting I'm playing Devils Advocate, I'd love to see a detailed report comparing the two options.