Yesterday I posed the question of which piece of transport infrastructure carried the most people during the morning peak. The answer is that at the moment they both carry about the same number of people, the difference of course is that the Britomart tunnel has the ability in the future to carry many many more people in the same amount of space as I intend to show you shortly. I have mentioned before how hard it seems to be to show just how much benefit the CRL brings to the city and this post is another intended to try and show some of this information in a different way to make it easier to understand.
The data for this post came from a couple of sources, the current PT information came from the Screenline Study which counted the number of people on buses and trains that entered the CBD last year. The vehicle traffic numbers come from Auckland Transport’s vehicle counts from which there are AM peak hour counts for the roads the cross enter the CBD. I have then mixed this information together along with information we already know about the capacity of the CRL and the EMUs to put these maps together.
A quick explanation about the maps:
- The lines represent places where people enter the CBD from, Red lines are access points from the motorways, Blue from local streets, Yellow from the ferries and Green is the rail network. The size of the line represent the number of people (not vehicles) coming via that route.
- For the streets the bus and vehicle counts are merged into one arrow, bus patronage is worked out at approx 30 people per bus for the current map, 40 per bus for the 2017 map and 50 people per bus for the 2022 map. In reality we probably won’t see utilisation that high but I thought it would be useful to show the difference.
- For the rail network the current count only includes people entering Britomart so other heavily used stations like Grafton and Newmarket are not included which take up much of the reserve capacity. The final map only shows the network at 60% capacity with the assumption that people would still get off at stations like Newmarket. Also before getting accused of accused of having a CBD only focus, the lines represent capacity to the Aotea station for visual purposes only.
First up here is what we have currently. The rail network is small but it is actually the 4th largest source of arrivals into the CBD when compared against each individual streets. You can also see the massive impact that buses from the North Shore and from the Isthmus and down Symonds St make, over 70% of people coming along these two corridors do so on a bus.
Next we see the what things might look like in 2017. By this time we should have all of our new EMUs running which will boost capacity as well as attractiveness of rail network. There are likely to also be significant increases in the bus network following the implementation of the planned improvements to it. In here I have assumed that only about half of the capacity of the EMUs arriving into Britomart is being used yet that line is already the single biggest on the map.
Lastly we see the impact once the CRL is opened, as mentioned the lines only represent about 60% of the available capacity as not everyone will want to head to the CBD. The capacity of the CRL absolutely dwarfs every other entry point to the CBD and it does so without impact to the surrounding streets once it has been built. It is also worth pointing out that the usage of the bus network has been greatly increased, probably more that we can expect in this time as combined it is around 65% higher than the bus patronage is now.
Going back to yesterdays post, to get the same amount of extra capacity we would need probably another 15 general traffic lanes into the CBD, around an extra 400 buses per hour or some combination of the two.