The A12 in Essex: why didn't they just build a motorway and have done with it?

[Patrick Harper]

The A12 shares the fate of the A1 in that D2 upgrades happened before a motorway was envisioned along its corridor, by the time this happened the D2 sections were largely 'good enough' for the job.

[c2R]

Yes, the nominal speed limit until you get to the 80 sign is 50, and the speed limit is 80 on the motorway, but guess how many people obey either?

That's an interesting question - I'd say that anecdotally, there seemed to be greater adherence to motorway speed limits in Sweden than in neighbouring countries, and I definitely saw more police visibly conducting enforcement on any time I've driven through (I don't think I've ever seen so many trees as driving on the E4 from Malmo to Stockholm!)... and I thought this style of sign was brilliant, if a but cluttered.



That said, the giant central reservation gaps where logging traffic appeared to use to conduct a turn in the road was somewhat on the terrifying side so I'm perhaps not surprised.

[Piatkow]

For people who think the A12 is bad now I remember walking down Brook Street hill in the late afternoon on a bank holiday. We were overtaking the traffic. I learned quite a few rat runs around Brentwood from the days when the A12 went through the middle of the town.

One think that has always puzzled me is that the Mountnessing bypass was built as D3 while only being a short link between the two older D2 Brentwood and Ingatestone bypasses. It was later downgraded to D2. Later sections were kept at D2.

[Bryn666]

For people who think the A12 is bad now I remember walking down Brook Street hill in the late afternoon on a bank holiday. We were overtaking the traffic. I learned quite a few rat runs around Brentwood from the days when the A12 went through the middle of the town.

One think that has always puzzled me is that the Mountnessing bypass was built as D3 while only being a short link between the two older D2 Brentwood and Ingatestone bypasses. It was later downgraded to D2. Later sections were kept at D2.

The road widens back to D3 towards Chelmsford as well for the Margaretting Bypass, which just introduces a 3 into 2 bottleneck before it goes back to D2 around Chelmsford. There's no logical design reason for this - and I would hazard a guess it causes numerous queues in the morning peak towards London.

This of course also went back down to D2 when it tied into Three Mile Hill, so a completely pointless D3.

[c2R]

The road widens back to D3 towards Chelmsford as well, which just introduces a 3 into 2 bottleneck before it goes back to D2 around Chelmsford. There's no logical design reason for this - and I would hazard a guess it causes numerous queues in the morning peak towards London.

I can sort of understand Chelmsford, because it would have been a significant destination for traffic before the ports became a factor, so it wouldn't surprise me if a lot of traffic heading south to this point used it as a destination.

As for the Brentwood bypass though, there's no logical reason if they knew that the M25 was going to be built... But perhaps they didn't, at that point, and in terms of road travel again it may have been Chelmsford focussed at the time...

[FosseWay]

Yes, the nominal speed limit until you get to the 80 sign is 50, and the speed limit is 80 on the motorway, but guess how many people obey either?

That's an interesting question - I'd say that anecdotally, there seemed to be greater adherence to motorway speed limits in Sweden than in neighbouring countries, and I definitely saw more police visibly conducting enforcement on any time I've driven through.

Various southern European countries, with Italy probably in the lead, have a reputation for playing fast and loose with speed limits to an outrageous extent. But nowhere I've been down south - and I used to live in Naples - can match certain roads in Sweden for speed limit breaking. It's not unusual on my local highway (158) to get platoons of cars (so limited by the slowest) doing into three figures in a 70 limit.

However, I think motorways outside urban areas might be an exception because the limits there are comparable to similar roads in other countries. It's all the city streets that are signed 30 but would be 50 in, say, Germany, or all the rural roads where NSL is 70 (100 in Germany) where you get the huge differential between what people do and what the signs say.

I can't say I've seen any more police enforcement here than in the UK, tbh. Perhaps they're all on the E4 and in Stockholm where they're needed more - they're all a bunch of wasters over there!

[Piatkow]

As for the Brentwood bypass though, there's no logical reason if they knew that the M25 was going to be built... But perhaps they didn't, at that point, and in terms of road travel again it may have been Chelmsford focussed at the time...

According to Wikipedia the Brentwood bypass was opened in 1965 so the plan probably pre-dates a firm decision on the route of the M25. At the time there were still S2 sections at Mountnessing and Margaretting and the route used the original Chelmsford bypass. International traffic came from about three ferries a day at Harwich.

As an aside, there was a breeder of fancy rabbits adjacent to the old Chelmsford bypass with a large sign advertising "Netherland Dwarfs". I often wondered what Dutch travellers off the ferry thought about it.

[KeithW]

According to Wikipedia the Brentwood bypass was opened in 1965 so the plan probably pre-dates a firm decision on the route of the M25. At the time there were still S2 sections at Mountnessing and Margaretting and the route used the original Chelmsford bypass. International traffic came from about three ferries a day at Harwich.

As an aside, there was a breeder of fancy rabbits adjacent to the old Chelmsford bypass with a large sign advertising "Netherland Dwarfs". I often wondered what Dutch travellers off the ferry thought about it.

In 1965 the nearest thing to what is now the M25 was the London Ringways plan.

The planned north and east sections of Ringway 3 and the planned south and west sections of Ringway 4 were incorporated into the M25 in 1975, construction of Ringways 3 and 4 were started in 1973 as I recall. For the full story try
https://www.roads.org.uk/ringways

[Glenn A]

The A12 should have been replaced by a D3M in the eighties, as the East Anglian economy was the fastest growing part of the economy by then and the A12 was becoming unfit for purpose. Also a so called M12 should have been extended along what was the A45 to Felixstowe.

[skiddaw05]

Just out of interest how much freight traffic is generated between Felixstowe and London, compared with Felixstowe and the Midlands - the A12/A14 junction appears somewhat underpowered for any significant A12N>A14E movements

[jgharston]

I'm always warey joining the A19 southbound at Inglby Cross

[KeithW]

The A12 should have been replaced by a D3M in the eighties, as the East Anglian economy was the fastest growing part of the economy by then and the A12 was becoming unfit for purpose. Also a so called M12 should have been extended along what was the A45 to Felixstowe.

Maybe but the inquiry to build the All Purpose Road that was became the A14 ran for many many years due to objections over the route to the Catthorpe interchange, trying to build a D3M motorway would probably have killed it stone dead. This was also a period when money was pretty tight due to a recession and the cost of supporting around 3 million unemployed. Even finishing the M20/A20 to the channel ports and proposed channel tunnel were paused. I know as I had to use the A20 from Ashford to Maidstone at the time which was not pleasant. When things started easing the first priority was finishing the M20. The last link from Folkestone to Dover was completed as a D2 All Purpose Road .

Here is what the CIHT has to say

History
When the Bedfordshire sub unit of the Eastern Road Construction Units was established its original design briefs included the M11 Cambridge Western Bypass, the A45 Cambridge Northern Bypass, the A45 Bury St Edmunds bypass and with a lowly priority the A45/A11 bypass of Newmarket. At that time the concept was perceived of a series of local bypasses on the A45. The emphasis to the west of Cambridge was on the improvement of the existing A45 towards St Neots.

The traffic work associated with the M11 and A45 in the Cambridge area however identified a strong demand for better northbound links with the A1 and the Sub Unit were given a brief to investigate the dualling of the A604 County Road between Cambridge and Huntingdon where Stirling Maynard and Partners on behalf of the then Ministry of Transport were developing proposals for a Huntingdon Bypass which would improve the connections to the A1 significantly. The A604 was already a problematic route for the local authority. Substantial commuter flows between Cambridge and Huntingdon caused peak hour delays which were exacerbated following the establishment of the new community of Bar Hill to the north of Cambridge.

Following Traffic Studies and a public consultation, the final decision identified the Green Corridor as the preferred corridor. Shortly afterwards the Bedfordshire Sub unit was appointed to undertake the identification and design of routes within the corridor.

Thus the final piece was put in place and the scene set for the implementation of a strategic trunk route linking the industrial Midlands to the East Coast ports.

The geometric standards have evolved, including those associated with the design of all forms of junctions, from at grade priority junctions to roundabouts and grade separated interchanges. In particular the operational aspects of weaving and merges and diverges are now better set out in the standards.

The applications of the design standards has resulted in a route which has similar characteristics along its length.

Here is what Felixstowe looked like around 1980 - not the colossus it is today. The A45 was pretty quiet in those days once you got east of Newmarket, the perceived priority in those days was the A604 from the end of the M11 to the A1 at Alconbury. The A45 from Cambridge to St Neots was a rather sleepy S2 road.

Felixstowe container port was MUCH smaller back then - see the 1980 plot plan.