Where is it?
South of Kingston, where the A3 Kingston Bypass becomes the A3 Esher Bypass.
It was spotted by Dave Ryan.
What's wrong with it?
For a start, the roundabout interchange with the A243 only has two lanes each way through the underpass — it's the narrowest point on the Kingston Bypass. The lane is dropped too early — the A309 takes a large amount of traffic but all of it has to squeeze under the roundabout first.
But that's not all. The A243 is a major road into Kingston and you can only reach it... southbound, when you're pretty much past Kingston. Northbound traffic either has to come off too early and go through Esher or too late at Tolworth. Of course, that doesn't stop some people: you can always exit northbound by pulling across the merging sliproad from the A243 and diving off down a residential street. Stupid? It wouldn't be necessary if the junction worked.
And still there is more. The underpass itself is not properly drained. It doesn't just form puddles when it rains, it forms the kind of lake that makes drivers of small cars come to a sudden stop half way down the slope, causing major delays in bad weather.
Why is it wrong?
The access problems can be explained quite easily. The Kingston bypass was built in the 1930s and originally returned to the A3 line by what is now the A309 here. In the 1970s, the Esher bypass was constructed, branching off the Kingston bypass at this point. Historically there had never been access to what is now the A309 from the west so it wasn't provided when the Esher bypass was built. The rest can only be explained by a lack of foresight in the engineering of the interchange.
What would be better?
The land actually exists to built south-facing sliproads from the A309, and free-flowing ones at that! But back in the real world, perhaps the drainage problems can be sorted out.
Right to reply
I know this junction well - one of the problems it causes is that as there is no access to the A3 westbound from the A243 all traffic from the area trying to reach the A3 has to join at Tolworth (the next junction east), which makes that junction overloaded, and squeezes more traffic through the two-lane section. And, of course, traffic leaving the A3 cannot do so until Tolworth.
I don't see access from the Esher bypass to the A309 as the priority - a more direct route to Esher is to leave the A3 at the previous junction (A244). Traffic into southern Kingston is more likely to benefit from provision of access to the A243. A solution would be to change the sense of the slip roads between the A3 and A309, so that instead of linking the A309 with the underpass, they link the Esher bypass with the roundabout. Yes, A309 traffic would then have to use the roundabout, but the much larger flows to and from the A243 could be accommodated.
Oddly enough the roundabout section works quite well, no traffic lights needed to stagger it out. It's only the A309 entrance which is bad. Approaching it from the A3 or either side of the A243 is ok, apart from small side road which appear half way up the slip road (common for this part of the A3!) and have cars darting out on the main road as if they didn't care about if they were alive tomorrow. The worst part is the merging of the A309 into the northbound A3. You actually have 5 lanes of traffic merging into 2 - the A3 northbound is virtually motorway standard before this junction, but just before it you have 3 lanes of national speed limit traffic squeeze into 2 lanes of 50mph traffic with a speed camera to boot! Add to this 2 lanes of traffic from the A309 forced into this to go into a very thin 2 lane underpass and you can imagine how messy it can get. Add the drainage issues to this and it becomes a nightmare! But overall it still works and flows better than its neighbour, the A3/A240 junction at Tolworth, which often has knock on effects onto the A3 itself.
The A309 is not a major route into Kingston. The A309 is part of the original Kingston By-Pass (and is still called Kingston By-Pass Road), and was used by traffic bypassing Kingston on the way to Esher, Guildford and Portsmouth. There are four good roads approaching Kingston from London, points east and Leatherhead.
Today, traffic going south now leaves the KBP at Hook West, with the A3 running along the new Esher By-Pass, which finishes at the junction of the A245 at Cobham and is of near-motorway standard. The old KBP, however, is still used by people getting from London to Esher, and from other points east (Sutton, Wimbledon, even Croydon) to Esher, Staines, Hampton Court, Walton and the M3. It's effectively across south London to Staines and the M3.
I agree that the Hook underpass is really too narrow, since going eastbound it takes all the traffic from Portsmouth and Esher, that is, five lanes of traffic, into two lanes. Although I've never encountered the sort of congestion you might expect.
Living myself to the north west of this junction, I would certainly appreciate south-east facing sliproads from the A309 onto the A3. This would enable me to bypass Esher en route to the M25 etc, Esher being a busy town these days. South west-facing slip roads from the A243 roundabout onto the A3 too make good sense, not least to improve the options available to traffic to get into Surbiton/Kingston from the south or out of the Chessington area headed south/south west. On the face of it there seems to be land aplenty to accommodate both extra options and this would also facilitate a 'meaningful' lane drop, from the A3 northbound carriageway.
I take all the exits off this junction from time to time. The aforementioned congestion, as 3 lanes goes to 2 for that 500M stretch through the underpass, is an obvious issue.
What I also find is traffic joining the A3 London bound (from Kingston and Chessington) has to contend with any traffic from the local road (Fullers Way North) about 100M after you join.
This causes all sorts of fun as people slow to about 5 mph to leave (its too tight to take faster) just as others speed up to A3 speeds and other people cross lanes (as mentioned above) to get to the exit. Ahhh!
Just close Fullers Way access.
The limitations of the hook underpass are all too obvious to see by people who use this frequently. My real beef with this junction is that no provision was made to access the A3 southbound when approaching from either direction on the A243. Therefore any traffic that may wish to by-pass Esher and head straight towards Cobham or Guildford either has to go to Tolworth to get access or, worse still, drive through Esher itself to achieve the same objective. I can only imagine, like a majority of these ideas, it was designed by someone who didn't have to make that journey and it somewhat nullifies the use of the A3 which has the capacity to handle extra traffic and take it away from Esher. Sitting in Esher most days, as I do, I often wonder if there actually is a by-pass.
The sliproads on this junction are a work of comedy. The London-bound A3 onramp, as others have commented, has local roads (most notably Fullers Way) branching off it at right angles and acting as an auxilliary route for Kingston-bound traffic that can't get off the A3 any other way. It also has a zebra crossing going across it right immediately after the roundabout exit, and a petrol station access at the same point. The southbound offramp from the A3 has peoples' driveways opening directly onto it for goodness' sake!
I live in Kingston and would make agree with pretty much all of this - what is not metioned here is that there is also no access to the A3 Southbound from the A243 - this catches me out time after time. Its ridiculous that the main Southbound route out of Kingston & Surbiton does not then connect Southbound with the main Southbound route out of South West London! And every time you forget this and turn right the roundabout you end up flying off down the A309 to Claygate & Esher and having to crawl past Sandown Park and thru Esher to get back on the A3 at the next junction!
Would also concur about the local access road - I use it frequently when coming in from A3 northbound and it involves cutting accross merging traffic, braking hard and then performing a very tight turn at slow speed. Dangerous! Its still better than the alternative of staying on the A3 for another mile then crawling thru Tolworth.
I am amazed there are not traffic lights on the Ace of Spades roundabout, but then I spent years working in tourism explaining to baffled overseas visitors why we put traffic lights on roundabouts... Madness!
The Ace of Spades was the first junction on the Kingston Bypass to have grade separation and its limitations are accounted for by its age. I'm not sure if what is now the A309 ever had three lanes but if not the lane drop would make sense. The stumps of the original concrete lamp posts were still visible last time I went through. I recall these were odd double bracketed posts with the underpass side head linked to the post by a long pole to make it lower
By all accounts in the 50s it was the wild west of the road network. D3 with narrow lanes (probably the first D3 in the country) and banked turns, it was totally derestricted until the 70 national road limit came in but had traffic lights at regular intervals and sort of resembled reigate avenue (A217) now
Add in 1950s cars with mechanical braking and brake fade and....suffice to say that I am told one garage (I think at the Combe Road junction) used to put the mangled wrecks on display in the forecourt to try and dissuade people from confusingt it with Brooklands race track and approaching traffic lights at 85 hoping they would stay green....In the end the whole road was grade separated largely for safety reasons. The 50 limit was much later, within the last 10 years or so.
The northbound A3 on the way into this junction is horrible. After the magnificent Esher Bypass, you are greeted by a 20mph limit drop, speed cameras and the road narrowing to 2 lanes, not to mention the A309 joining in while there are still only two lanes. This leads to huge queues, that sometimes even stretch back to Esher Common. The solution is to demolish the A309 slip road that joins before the underpass, and replace it with a slip road from the A3 to the Ace of Spades roundabout, which the A309 merges with before the roundabout. This would also solve the problem with the entrance into Kingston. Sadly, I don't think anything can be done about the lane drop, apart from the speed limit drop being less drastic. As for the way out of Kingston southbound, there is plenty of space to build a slip road onto the A3.
From a flat SE of the Toby Jug roundabout I watched the underpass at that junction being dug/built. My dad had a shop 100 yards east of what was then the roundabout. As a schoolboy at Tolworth Boys Secondary (ground floor of what is now Tolworth Girls in Fullers Way North) I also watched the Ace underpass being built. The excuse given by the powers-that-be for NOT connecting the A243 to the new (1970s) Esher Bypass (south/west bound) was that it would increase the volume of traffic on the A243. So instead they lumbered Esher with traffic which should be consigned to the new A3 - dumb or what?
Personally, these days from Chessington where I now live, I use the A243 (southbound), the B280 and A244 to access the Esher Bypass/A3 (causing increased misery to the residents of Malden Rushett and Oxshott).
A link from the A243 to the A3 south/west bound would be a logical and relatively simple matter (though expensive at today's prices) requiring no major bridge works, and would ease congestion on a number of surrounding roads, junctions and towns.
However, to eliminate the two lane (in both directions) bottleneck under the 'Ace' underpass would require a prohibitively expensive and far more imaginative scheme, which I believe would be possible if there was a will.
It would involve dropping the north/east bound A3 into a three lane tunnel (roughly where the A309 link currently joins it), so that it continues under its present alignment, at the same time removing the link from the A309 at that point (more of which later). This tunnel would re surface adjacent to the Tolworth Recreation Ground (rear of Tolworth Girls) where a strip of land would be acquired to provide a joining slip road from the 'Ace' roundabout which would run above the new tunnel to this point and swing out onto the strip of land as the main road rose to the surface, enabling the two to merge. This strip of land only needs to be two lanes wide.
This would also allow for a widening to three lanes of the south/west bound carriageway, which would also run above the new tunnel as there would now be ample room through the current underpass. (Yes, I know. The new tunnel would have to go very deep because of the dip in the underpass, but if they can dig Cross Rail under the city of London, a tunnel under the 'Ace' would be a breeze.) There would also be room through the underpass to accommodate a single lane slip road from the A309 in the opposite (north/west bound) direction. This would merge with the (north/east bound) slip road from the roundabout near the Fullers Way North junction where the slip road currently merges with the A3 (Though preferably a bit beyond the Fullers Way junction to eliminate the dangerous crossovers mentioned by previous correspondents).
While all this was being done, modern drainage would have to be installed to take care of any flooding problems.
No houses would be lost. Only a small strip of (unoccupied) land two lanes wide would be acquired. Traffic congestion would be eased. BUT, a lot of money would have to be spent.