Josh Arbury has done a post on Len Brown’s rail plans. It includes a picture of the underground rail loop and it got me thinking about the optimal way to utilise the new tunnel for the Western, Southern and Eastern Lines.
Imagine a Southern line commuter getting on at Greenlane wanting to go to the new K’ Rd station. Will all Southern line services go via Britomart, forcing our commuter to an extra long journey? We could make all services take advantage of the tunnel, so that the sequence of stops goes Newmarket, Grafton, Symonds, K’Rd, Wellesley, Britomart. But what if the same commuter wanted to go to Britomart? That’s four extra stations to endure.
We could get our example commuter to transfer at Newmarket on to another service, but what service would that be? It’s a similar problem for other rail commuters on the Western and Eastern lines as well. Because each of the three main lines forks as it enters the CBD loop, there is no right answer here. We may be pretty much forced to make users transfer if they don’t want to take the default fork in the line.
But I think that there may be a way around this conundrum. Enter the “cyclone” rail system:
In this strategy, there are three lines – green, red and yellow, corresponding to the Western, Eastern and Southern lines. Throughout the day, each service alternates between the left and right fork as it approaches the inner city rail loop. In the map above, for instance, a Green C train would enter the loop going clockwise, going via Symonds, K’Rd, Wellesley, Britomart, Parnell, Newmarket, Grafton and Mt Eden, before returning out west. The next inbound train would be the Green A(nti-clockwise) train, and would visit the same stations, but in reverse. Same goes for the Yellow and Red lines. The service then continues around the loop, and back out the way it came in. I imagine at peak the A and C trains would only be 5 minutes apart.
Some good outcomes of this arrangement are:
- Its easy to understand. Kind of like the Link bus service is now
- If you get on the wrong A or C train, you are still going to end up at an inner city station you intended to alight at, it will just take you a bit longer
- Transfers to other lines are very easy, as you should be able to transfer at any station on the inner city loop to the line of your choice
- Travelling around the inner city becomes very easy, you just need to know the fastest direction to your intended destination, and make sure you take a colour that isn’t about to pull out of the “cyclone’. e.g. if you are at Britomart wanting to get to Newmarket, take a Green or Yellow “A” train
- Trains can be branded as they will always run on the same lines. For instance, all yellow line trains could actually be yellow
- It is scalable to include the Northern line train when it enters service. The “C” train would take you to Britomart, while the “A” train will take you to Wellesley.
What are your thoughts? I’ve posted this as an idea on our ideas forum so you can vote and add comments there.