Where is it?
Halfway around the A720 Edinburgh City Bypass, where two of the city's radials cross the bypass and each other.
It was nominated by Chris Williams.
What's wrong with it?
Imagine, if you will, the city of Edinburgh. Around its southern fringe lies the A720, otherwise known as the City Bypass, a grade-separated dual carriageway (complete with hard shoulders and motorway-like restrictions) that speeds traffic around the urban area. It's like some kind of dream.
However, largely thanks to this junction, if the A720 is any kind of dream, it's the sort that makes you wake up screaming at three in the morning. It's pretty obvious from the diagram what's wrong with it — it's a roundabout. Traffic chaos day and night is caused by the fact that this junction, in the middle of what is effectively a motorway, is one flyover short of adequacy.
Naturally, traffic engineers have done their best to entertain those stuck in the congestion this roundabout causes by surrounding it with cheery red, amber and green disco lights.
Why is it wrong?
There are two schools of thought on this one, and each is equally plausible. The first is the more optimistic; when the Bypass was designed and built it was thought that the volume of traffic entering or exiting the road here would be a significant proportion (ie, the flows of traffic between the two arms of the A720 would not be heavy enough to warrant grade separation). With the benefit of hindsight (and all the thinking time that a typical Sherriffhall traffic jam permits), it's clear as day that this idea was wrong.
The other, more frightening, answer is that the junction is built on the site of old mine workings, and that this made grade separation impossible. The ground is not stable enough to support a flyover. This is backed up by the fact that the design of the junction does not even leave room for future grade separation. If this reason is true, then the future looks grim for regular users of this junction.
What would be better?
A flyover and a free-flowing A720. Or an underpass. Anything. Please. Quickly.
Right to reply
3 options now being considered by Transport Scotland. 2 dumbbell layouts and a grade separated roundabout. Details on Transport Scotland website.
Improvements to the junction announced as part of the SE Scotland City Deal - quoting costs of over £100 million (which seems a bit excessive to me!)
Doesn't mean anything imminent though - work not likely to begin for at least 18 months.
I was on the local Community Council which covers the Sherifhall Roundabout, when we got a presentation from relevant authorities as what the junction at Sherifhal would look like, we were told it would be a 3lane carriageway the full length of the bypass. Can you imagine how we felt when we realised it was going to be 2 lane. When they decided to purchase properties which should have been purchased to allow 3 lanes they decided for economic reasons to purchase enough for a 2lane carriageway and we now know the consequences (penny pinching comes to mind) but who are we to complain we are only the road users. It begs the question what kind of brain do the designers of roads have. Do the powers that be use this monstrosity of a badly designed that they have devised for our capital city, if so they should be ashamed of themselves when you see what the width of the road should have been, not what we got. It has already cost a fortune to get the roundabout updated to what it is now (typical false economy) think how much cheaper if they had done the job right in the first place.
EXACTLY the same as when they made part of the M5 two lanes instead of at least three and EVERYONE - Police, Public, AA etc all said it would be ridiculous to do that. Sure enough, just a few years later the still quite new bridges had to be knocked down (or the hard shoulder was used). 'False economy' is certainly correct. The British are fantastic at it.
Local press suggests that the whole improvement may be ditched given the budget deal with the Green Party. The money is to be used to invest in public transport.