There seems to be a huge amount of discussion (and disagreement) about the proposals for Highbury Roundabout.
Taking the issues a point at a time; If there is one thing we can nearly all agree on, I think it is that gyratory systems are generally a Bad Thing, as they encourage traffic to travel at greater speeds, and are much more scary to cross. They are also very scary for cyclists. The classic example of this was Norman Foster’s interventions to Trafalgar Square, where a once scary racing circuit is now a much calmer, and more slowly-moving two-way traffic system, with the Northern arm pedestrianised, and Trafalgar Square completely redefined as a major public amenity and events location.
So, we can agree that closing an arm of Highbury Roundabout is almost bound to be a Good Thing. But then the question is, which arm:
There are strong and vocal supporters of proposals to close each of the four arms of the roundabout, all have whom have developed arguments as to why their proposal should be favoured. I won’t go into the arguments here, but rather stick my neck out and say I think the current proposal to close the western arm is the right one, on the basis that the large majority of people movements in the area are associated with and gravitate towards the station, and that common sense suggests that this would be the most obvious link to join the central roundabout area to the public (ie pedestrian) realm, and would provide the best-used additional pavement area.
However, having reach this conclusion about arm closure, I am personally horrified at the amount of space traffic engineers have taken from the central roundabout area to remodel the roadway and cycleways. The highway round the other three sides of the former roundabout is currently shown at six lanes wide, or seven, if you count the 2-way cycle route, which is far worse than the current racetrack round the roundabout. This flies in the face of public amenity and common sense. It is my impression that traffic engineers still see their role as trying to move traffic through an area faster, whereas I think most people would agree that traffic calming is what we need at busy junctions such as this - after all, that is the intended purpose of removing the gyratory.
At the moment, the traffic scheme proposes to remove 27% of the central roundabout area and give it over to traffic movements. (If you zoom into the map, you can see in red the current outline of the roundabout.) I think we have to push back on this, and demand that pedestrianisation be achieved without loss of the valuable green space that is the roundabout itself: In a Borough with so little green space it seems wrong to lose such a large amount of that green space in the name of maintaining traffic flows.
I also have my doubts about the merit of introducing quite so many cycle lanes, when the route one would have to take on a bicycle is in several directions quite counter-intuitive. Looking at the proposed layout, and imagining what I might do if I wanted to travel from Holloway Road to Upper street on my bike, I would probably opt to just stay on the road rather than criss-cross over the various convoluted cycle routes. In my experience most cyclists tend to take the most direct route rather than follow cycle paths that take longer. The cycle routes need to be logical and straightforward, or some cyclists may take matters into their own hands and start using the western (pedestrianised) arm as an informal alternative route, which I'm not sure would be the best solution either.
And then finally, there is the discussion about whether to remove the railings around the Arboretum, (so-called because it is a collection of various tree species, originally planted as an experiment in 1959, to investigate the resistance of various tree varieties to exhaust fumes). Again, personally, I think the railings should be removed, or we won’t get the benefit of a major new public open space, and the rebalancing of the public realm between motorised vehicles and everyone else. The removal of all the railings on the Angel section of Upper Street a few years is a good demonstration of the success of this rebalancing principle. However, I do think a lot more discussion is needed about how we landscape the central area so that it can take the wear and tear of being a public open space.
Overall, I think we should commit to closing the western arm, push back on the loss of the green space at the expense of traffic, revisit the cycle lane proposals, and keep talking about the use of the central area.