Girton interchange: adding the 'missing' slips

[jackal]

Girton interchange is currently being upgraded to remove the weaving space and create a high speed link for the A14 (see plan here). However, there are ongoing proposals for further upgrades to add some or all of the 'missing' slips connecting the A428 to the M11 and A14. For instance, links to the M11 are apparently favoured by the Greater Cambridge Partnership (formerly the City Deal), who hope to get them included in RIS2 (link).

Highways England do not currently plan to provide such links, but have outlined three concepts for adding them that would be compatible with the design under construction:

https://infrastructure.planninginspecto ... ndards.pdf

[jackal]

Here are a few more speculative plans for adding the missing links.

Smarter Cambridge Transport, a local pressure group that want to add a park and ride site within the interchange, have their own suggestion:



They also have a version that adds access between the A1307 and A14 East:

Finally there's this ultra-ambitious Highways Agency plan from 2009, redrawn by Truvelo (not compatible with current scheme):

[jackal]

"Highways England has said it was considering overhauling the Girton Interchange and turning it into an all-ways junction, which would result in less traffic on surrounding roads."

https://www.inyourarea.co.uk/news/cambr ... rush-hour/

[thatapanydude]

The first redesign as shown with the link from the A428 via the roundabouts to the M11, would be a suitable fix and easy to do. While not free-flow the amount of traffic using this would be limited so a free flow would be an overkill. Additionally you can close off Junction 13 which will split the traffic evenly from St Neots (A428) to J14 or into Cambridge.

[Big L]

Good to see they've used a current image at the top!

Also

...There is currently no eastbound access to the M11 from the A14...

I'm sure I've made many journeys on the eastbound A14 on which I have had to actively choose not to access the M11.

[trickstat]

The first redesign as shown with the link from the A428 via the roundabouts to the M11, would be a suitable fix and easy to do. While not free-flow the amount of traffic using this would be limited so a free flow would be an overkill. Additionally you can close off Junction 13 which will split the traffic evenly from St Neots (A428) to J14 or into Cambridge.

Vested interest - Junction 13 is the best one for the athletics stadium!

[KeithW]

The first redesign as shown with the link from the A428 via the roundabouts to the M11, would be a suitable fix and easy to do. While not free-flow the amount of traffic using this would be limited so a free flow would be an overkill. Additionally you can close off Junction 13 which will split the traffic evenly from St Neots (A428) to J14 or into Cambridge.

Hold on a minute there.

Junction 13 provides access to the Park and Ride, the new University West Development, the High Cross Site and a large University site. Close J13 and you will be large volumes of traffic into Central Cambridge. There is so much traffic coming off the M11 at J13 Northbound that at peak times it queues back down Lane 1 sometimes all the way to J12. In the evening rush traffic streams up the Madingley road heading for the A428 and the M11. Its about the only route to the M11 that does flow at all well.

Heading to those facilities via J12 takes you down here.
https://www.google.co.uk/maps/@52.19694 ... authuser=0

What HE are suggesting will prevent traffic flowing between the A428 and M11 having to fiddle their way around minor roads which will be essential if the route from Oxford to Cambridge is upgraded. The worst congestion is on the Madingley road west of J13 heading for the A428, given that was my route home I know that one rather well. You could join the end of the queue for the A1303 to M11 J13 junction at the Madingley Mulch roundabout just off the A428. Some days it took me 20 minutes to travel less than 2 miles.

[roadtester]

I really don't want to come across as a moaner because the A14 around Cambridge has already seen so many decent improvements for which I am immensely grateful, but it would be nice if they could have accepted the IMHO inevitable and incorporated these movements into the recent schemes to upgrade Huntingdon/Cambridge and the Cambridge Northern Bypass section.

[thatapanydude]

The first redesign as shown with the link from the A428 via the roundabouts to the M11, would be a suitable fix and easy to do. While not free-flow the amount of traffic using this would be limited so a free flow would be an overkill. Additionally you can close off Junction 13 which will split the traffic evenly from St Neots (A428) to J14 or into Cambridge.

Hold on a minute there.

Junction 13 provides access to the Park and Ride, the new University West Development, the High Cross Site and a large University site. Close J13 and you will be large volumes of traffic into Central Cambridge. There is so much traffic coming off the M11 at J13 Northbound that at peak times it queues back down Lane 1 sometimes all the way to J12. In the evening rush traffic streams up the Madingley road heading for the A428 and the M11. Its about the only route to the M11 that does flow at all well.

Heading to those facilities via J12 takes you down here.
https://www.google.co.uk/maps/@52.19694 ... authuser=0

What HE are suggesting will prevent traffic flowing between the A428 and M11 having to fiddle their way around minor roads which will be essential if the route from Oxford to Cambridge is upgraded. The worst congestion is on the Madingley road west of J13 heading for the A428, given that was my route home I know that one rather well. You could join the end of the queue for the A1303 to M11 J13 junction at the Madingley Mulch roundabout just off the A428. Some days it took me 20 minutes to travel less than 2 miles.

I am with you on that - in my own scenario coming from St Neots, if junction 13 was to remain open I would use that shortcut to the M11 rather than go via Girton if after an upgrade it wasn't free flow. Closing J13 would of course cause issues but a compromise solution might be to ban right turns from the A1303 onto the M11 South which would keep any J14 upgrade useful and improve the flow out of Cambridge somewhat.

[KeithW]

I am with you on that - in my own scenario coming from St Neots, if junction 13 was to remain open I would use that shortcut to the M11 rather than go via Girton if after an upgrade it wasn't free flow. Closing J13 would of course cause issues but a compromise solution might be to ban right turns from the A1303 onto the M11 South which would keep any J14 upgrade useful and improve the flow out of Cambridge somewhat.

It doesnt affect the flow out of Cambridge as east of the junction the configuration is 2 lanes out and 1 lane, it has the potential to block inbound traffic in but in the 20 years I used that year I cant ever recall seeing any major delays. The right turn lane seems long enough to cope. Inbound traffic used to cope quite well as it was 2 lanes inbound and one out. The real bottleneck inbound is where they turned lane 1 into a bus lane.

https://www.google.co.uk/maps/@52.21507 ... authuser=0

The real problem with respect to Cambridge is commuter traffic is trying to get into a what is now a major centre of employment from either the A14 or M11 on roads that were barely adequate 40 years ago when what are now major centres such as Orchard Park, the Science Park, High Cross etc were green fields. This is still getting worse, the University West site can only be accessed via Madingley Road or Huntingdon Road and its surely only a matter of time before the university astronomy centre moves out of town and is turned into another commercial development.