Over the last two weeks of May Camden Cyclists investigated the evening rush-hour ‘Judd jam’, carrying out some traffic counts to understand it and suggesting some solutions. They acknowledge their counts are small and, compared with official counts, very rough and ready – but they match what lots of us will have seen happening ourselves.
Their report has been forwarded to Marchmont Voice – here it is …
The jam is caused by the large number of motor vehicles wanting to turn west from Judd into Euston Road. The lights give priority to Euston Road, a red route, which allows for only 2 or 3 Judd vehicles to get through for each cycle of the lights. Thus the traffic backs up on Judd Street.
The traffic travelling N on Judd is primarily coming from traffic travelling westbound (WB) on Guilford Street, though some comes from WB traffic on Tavistock Place (ratio approx. 77/23). Though we have no counts to confirm it, we believe that the majority of this traffic comes from Gray’s Inn Road and that it is using Judd as the final part of a rat-run to avoid the King’s Cross junction.
The WB traffic on Guilford that does not go N to join the Judd jam carries on to Russell Square where it either turns N to join the Woburn jam or S (to go places we did not investigate). The N/S ratio is approx. 43/57 but we think that is a false reading since the NB traffic on this lights-controlled junction is so heavy that, if the Guilford NB traffic respects the yellow box, the lights can run through multiple cycles with no NB traffic getting across (despite all the hooting from behind). We suspect that much of the traffic that turns S is actually destined for the N but trying another route (such as all the way around Russell Square).
* In our count for the N turn onto Woburn we included the small number of vehicles that use Herbrand and Coram as a rat-run through to Woburn. See the evidence here
* The WB Tavi traffic turns N onto Judd by using the Wakefield / Handel dogleg.
* The WB Guilford traffic turns N towards Judd by using the Lansdowne / Brunswick dogleg.
Drivers are willing to sit in traffic jams for long periods of time, making the street environment for residents and other road users extremely unpleasant. From the behaviour we witnessed we believe that many drivers are continuously reassessing their route, selecting from possible options at each junction, based on the weight of traffic they see ahead. In the evening rush-hour this area suffers from traffic trying to travel north or west and, like water, it finds its own level, filling all possible routes equally to the detriment of all.
One idea might be to change the traffic light sequence at the Judd/Euston junction to give more time to the flow from Judd. However that would reduce the flow from the east along Euston Road, which would result in a greater build-up on Gray’s Inn Road, which some drivers would avoid by choosing the Judd route, and so it would all end up the same as before the change to the lights. So that would not solve anything, and would only tend to enforce the idea that Judd should be taking this level of traffic.
TfL and Camden have already decided which roads can take heavy rush-hour traffic – see this page 22 of the Camden Transport Strategy. In this area these include: Gray’s Inn Road, Euston Road, Woburn Place. And does not include: Judd Street, Tavistock Place, Guilford Street, let alone Wakefield, Handel, Lansdowne, Brunswick, Herbrand, Coram.
North and West bound traffic is using these local streets are if they were part of the SRN. TfL and Camden need to redirect that traffic back onto the SRN. Our suggestions would be to implement some or all of the following:
• Close the left turn from Judd onto Euston,
• Close the Wakefield / Handel dogleg to through traffic,
• Close the Lansdowne / Brunswick dogleg to through traffic,
• Close the Herbrand and Coram rat-run.
TfL and Camden have already consulted on traffic schemes which would achieve some of these measures and we hope they can quickly implement something to resolve the traffic problems in this area.