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Saturday, 3 August 2024

A Tale Of Two Roundabouts

This post comes from London where two roundabouts have been redesigned to add protected cycling space.

The first is the Old Street junction which is right on the border of the boroughs of Hackney and Islington, but part of the Transport for London Road Network (TLRN) and is so a strategic road for motor traffic.

The overall design for the roundabout was "peninsularisation" whereby one of the areas between two of the four roundabout arms was closed to traffic and the remaining three sides converted to two-way traffic. This essentially leaves the junction as a pair of closely associated signalised T-junctions.

The north and east arms are on London's Inner Ring Road, the southern arm heads towards the City of London and the western arm heads towards Westminster, and so there's lots going on traffic-wise as well as it being a transport interchange for buses with the Underground. Just north is the Moorfields Eye Hospital and the local area has lots of business and leisure destinations as well as there being lots of people living there.

The old roundabout had been signalised for years and there were two-stage pedestrian crossings on three of the arms (City Road east without any) and it was a pretty grim place to be. There were also a network of subways feeding the Old Street Underground station on the Northern Line which is under the centre of the junction. The project has been going on for ages as it includes works to the station, but the road works are pretty much complete.

A one-way cycle track meets traffic signals with an ahead lane and a right turn lane which crosses the road in parallel with a pedestrian crossing.

For cycling, the junction now has a series of with-flow cycle tracks which are at carriageway level and protected by narrow traffic island strips. At three locations, the cycle tracks split into two lanes which means that people leaving the junction carry on ahead with those crossing an arm having little right turn lanes. Above is a photograph of the approach to the southern arm with the left lane heading south to the City of London and the right turn lane a crossing to access City Road westbound.

The arrangement provides one-way cycle crossings which operate in parallel with pedestrian crossings in two locations and traffic movements are separated out in essentially hold the left arrangements. However, this doesn't apply to cycle movement which crosses the eastern arm because unfortunately, there is no pedestrian crossing here as was the case with the old layout. The cycle movement is quick here, but it is stingy not to have added a pedestrian crossing.

Timber and steel seating benches and tables with a long rectangular rain garden.

The closing of the northwest side of the junction has released lots of space back into the public realm and as well as this giving the opportunity for better access to the station, there is much more space for people to flow as it's a very busy pedestrian area. It has also providing space for public seating and rain gardens (above); and yes, I took the photo a few months back when it was a little colder.

A line of closely spaced fat HVM bollards with a cycle track and road beyond. The road has a white Tesco lorry on it.

Of course, being the UK, the project has now attracted hordes of hostile vehicle mitigation (HVM) bollards which, as usual, create a blot on the public realm landscape. The designers have tried to make some useful adding cycle hoops, but they don't work properly as one cannot lock a front wheel to the HVM bollard (above).

From a cycling perspective, the junction is so much better than mixing with traffic, but there are issues. There is no way to turn right from Old Street west into City Road south and so you have to remember to turn off before the junction into some of the old local cycling network. It's not the end of the world, but it's not intuitive. The pedestrian crossings all cross the cycle spaces rather than being floated which means there is going to be mixed levels of compliance as signals are for motor traffic rather than people management.

The approaches and exits to the junction are also hit and miss because while the signals generally allow progress to be made ahead of traffic, you end up being dumped back into general traffic or bus lanes. Hopefully the links will be addressed in the future. Here's a video of the junction and a little extra to the east where access to Cycleway 1 can be found.


The other roundabout I wanted to look at is 4.25km to the north east in Hackney, the Lea Bridge Roundabout and yes, if you've followed this blog a while, that name will ring a little bit of a bell. 

The junction is another large TfL-managed roundabout which carries the north-south A107 with the western arm carrying a local road, Kenninghall Road, and the eastern arm forming the A104 Lea Bridge Road. Yes, that Lea Bridge Road which passes from Hackney to Waltham Forest some 800 metres to the north-east and which I looked at for my 400th post.

A mini bus station area in the centre of the roundabout with several red London buses parked up.

In terms of footprint, this junction is pretty similar to Old Street, but the changes are far simpler and in general a fair model for efficient retrofit for roundabouts like this. The roundabout form is kept as it was, that it is to say a four arm roundabout with two stage pedestrian crossings over each arm. The curious bus terminus in the centre has also been kept and it remains with its signal-controlled exit back into the circulatory area (above).

From a cycling perspective, this project provides a further section of Cycleway 23 which connects Dalston to the Waltham Forest part of Lea Bridge Road and which crosses the roundabout from Kenninghall Road (through filtered streets).

A one-way cycle track split into ahead and right lanes. The right lane crosses a road with a pedestrian crossing behind and the pedestrian crossing is accessed by crossing the ahead cycle track lane.

The design approach is very similar to aspects of Old Street. The junction is now encircled by with-flow cycle tracks that split into two lanes at the roundabout exits with an exit ahead and right to cross the arm in parallel with pedestrians. It's a way of adding cycling into an existing traffic signal arrangement which should be broadly neutral in capacity terms and I think it largely keeps the same number of general traffic lanes. 

The cycle crossings, like pedestrians are in two stages, but I can't quite work out how they operate as in most cases, I caught a green over both crossings most of the time. I suspect some of this will be responding to motor traffic flows.

Am uncontrolled crossing from a grey footway over a black cycle track to a waiting island with grey tactiles. There is then a signalised crossing to a large island with red tactiles and this is all reversed in the distance to the far side of a roundabout arm.

From a walking point of view, the project hasn't really changed much from the crossing the main carriageway point of view, but of course there are now cycle tracks to cross to get to the main crossings. In all cases, the cycle track crossings are uncontrolled and very annoyingly offset (see above). The tactile paving of the uncontrolled crossings is the same colour as the paving which is very poor indeed as dark grey would provide the contrast needed here.

The northern and southern arms drop cycle traffic back with general traffic and buses, but the project also includes pushing C23 to the Waltham Forest boundary, and so here there are with-flow cycle tracks on Lea Bridge Road.

A grey footway with a black cycle track to the right and a road to the right of that.

The Lea Bridge Road section is very compromised. The south-westbound bus lane has been retained, so although some of the space for the cycle tracks might have been nibbled from the edge of the carriageway, it also takes away a strip of footway on each side of the road which means narrow footway-level cycle tracks. There are various vehicle crossings which trip the cycle track to the right which is a significant issue for the stability of those using more than two wheels (above).

A red cycle track left and buff footway right separated by a grey paved strip running through parkland.

A little further east and eastbound cycle traffic is taken into Millfields Park. Westbound cycle traffic will be out on the street heading south-westbound with a south-westbound bus lane. The surface of the cycle track is a nice red colour (above), but it is not machine-laid and is one of the worst surfaces I have cycled on in a long time, and for some reason, it has swapped sides with the pedestrian path since consultation

Anyway, this is for a revisit another day when the Lea Bridge Road works are complete and so I'll leave you with a video of the roundabout, but with the bonus of me heading into Waltham Forest to show that London is slowly connecting itself for cycling.

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