Eamon Ryan (Dublin Bay South, Green Party) | Oireachtas source

Perhaps I will comment on that point then. The airport cap and the metro were mentioned at the same time. They are connected. The airport cap came from our planning system and not our political system. It came from a recognition that we were really constrained on our roads around the M1 and the M50. The M1 is our busiest, most congested and most constrained road system, as are the roads around it going to the airport. This is real. Having been involved in this issue for many decades, I remember talking to the Arup engineer who designed the widening of the M50. We put in all the Red Cow upgrades and all the massive M1 and M50 junctions around the airport. I remember asking the engineer if that was it and he told me that was it. He said we could do no more, there was no way to expand the capacity there because it was at its maximum. With absolute certainty, it was said the road would gridlock.

I was involved in the planning hearing for the widening of the M50. I think the inspector's name was Devlin. We presented the analysis to show it was guaranteed to fill up, which is where it is now. There is this really chaotic system where it gridlocks if there is an accident or any sort of change. The roads around the airport are the same. This situation cannot be changed by building more roads. That is the first premise. This is a constraint on the airport. If the airport continues to grow, and it will do so, and it is a car-based transport system, we get tailbacks of many miles. Was it two-mile tailbacks that were modelled recently in respect of coming and out of the airport? The whole thing does not work then. The M50 gridlocks. There was, therefore, a reason the cap was put in place. I mention this background because it is one of the other cases for the metro. I mentioned the metro earlier. It is really a spine to build housing up in Lissenhall and Swords, all the institutional connections and having a north-south connection. One of the other benefits of having a metro is that it addresses the traffic capacity issue around the airport, which is a physical reality that cannot be ignored. It is a mathematical certainty that we will get all these massive tailbacks unless we have public transport alternatives.