Congestion and Bus Services

The following article has been written by Peter Osmon FIET, and was submitted for publication on 20 August 2018.

Overview

Efficient and reliable bus services are important to London’s economy and to the many Londoners who use them every day: but the traffic congestion, due to moving and parked vehicles, encountered by buses can double journey times and many thousands of hours of Londoners’ lives are wasted every day due to service delays attributable to congestion. Our buses share road space with great numbers and varieties of other vehicles. Resulting congestion negates the reliability and ups the cost of providing bus services. Private cars are the most obvious source of this congestion. But a full quantitative treatment could attribute bus service delays to all the various categories of vehicular traffic.

Technological changes- App cab services, Internet shopping deliveries and the favourable economics of electric cars- are new and growing sources of increased traffic congestion- further damaging to the cost of and reliability of our bus services.

What is to be done about London’s congested bus routes?

Measures which would give more road space priority to buses, including extending bus lanes, could shift some of the congestion burden from buses onto private cars. The Mayor needs additional powers to counter the threats from technological change to bus services. The author favours regulation of Internet delivery services to minimise interference with other traffic and TfL taking over provision of App cab services to provide a premier class point-point passenger service alongside London’s standard class bus service.

Traffic congestion encountered by buses can double journey times

Reducing this congestion would improve bus services, with consequent service cost/revenue benefits, as this example shows.

Consider a hypothetical bus route comprising 16 stages with service intervals of 8 minutes. Suppose an average stage duration of 4 minutes during the peak and 3 minutes off-peak. Then, during the peak, a bus travels the route (in one direction) in (4 x 16) = 64 minutes and 64/8 = 8 buses are needed to maintain the service in each direction: 2 x 8 = 16 buses in total. Off-peak only 2 x (3 x 16)/8 = 12 buses are needed.

More generally, if congestion induced delay can be reduced by N%, then the number of buses needed to maintain the service level is reduced by N%. Alternatively, the same number of buses can provide a service with N% shorter intervals- less crowded buses likely attracting (some) more fare paying passengers.

Incremental reductions in congestion would generate these benefits incrementally.

Sources of congestion

Bus services are affected negatively by two kinds of vehicular congestion: dynamic- slow moving traffic on crowded roads; static- waiting or parked vehicles restricting the capacity of the roadway. Evidently dynamic congestion is responsible for longer bus journey at peak traffic compared with off-peak, whereas static congestion is a more constant factor- extending journey times throughout the day.

London’s bus routes are carried by a variety of roads, reflecting the historical incremental development of our city, and which are more or less fit for the purpose. The variety of congested routes is exemplified by conditions along three Inner NW London roads:

A41: a relatively modern 4 to 6 lane radial road, with significant congestion only at peak times.

A5: an ancient 3 to 4 lane radial road, with significant congestion along its length, especially but not only at peak times.

A407: an old 2 to 3 lane orbital road, frequently congested and with tailbacks at approaches to intersections.

Road space occupancy of bus travel per person compared with car travel

An example illustrates this issue. Compare the road space occupancy per person of a 5m long bus with 30 passengers and a 3m long private car transporting just its driver-

(a) Both vehicles stationary: (30/15 = 2 persons per metre of road) compared with (1 person per 3m of road): bus travel makes 6x better use of precious road space

(b) Both traveling at 15 km/h and separated by stopping distance of 10m: 30 persons per 25m of road compared with 1 person per 13m of road- bus require 30/25 = 1.2 person per metre of road, whereas car travel requires 13m of road per person: the moving bus makes more than 10x better use of road space.

Evidently there is an efficient-use-of-scarce-road-space case for giving buses priority over cars. We are already accustomed to giving buses a degree of priority by means of bus lanes, but this priority is nowhere proportional to the factor ten that fairness would imply.

More road space priority for buses would shift some of the congestion burden from buses onto private cars (and some motorists might then choose to use public transport instead of their cars):

Currently, buses and private cars share the roadway along bus routes, with buses having a degree of priority by means of bus lanes. Some further measures that would provide additional road space priority for buses are as follows.

Extension of Bus lanes:

so they are operational for more of the day

so they extend fully up to intersections.

Introduce Bus lanes:

into 3-lane roads at the approach to intersections.

Smart traffic light control:

Lights turn green for buses as they approach intersections

Respect for bus priority:

Require other vehicles to give way to buses at intersections etc.

Require other vehicles to maintain good lane discipline alongside bus lanes.

Enforcement of the above using video cameras installed on the sides and front of buses together with automatic number-plate identification and prosecution- as with Congestion Zone Charging- would surely be economical and effective. Revenue from fines would likely more than cover the cost of these measures.

New contributions to congestion, consequences of Londoners’ adopting new technologies, threaten the future reliability of bus services: the rapidly increasing road traffic related to Internet/WiFi enabled services- cabs and retail deliveries, and the attractions of electric motoring. These will have to be managed.

Managing the volume and behaviour of “cab” traffic

There is a legitimate demand for a “premier” passenger transport service in London- speedier than buses and also point-to-point: cabs. Increased pressure on road space for private cars would increase demand for the service. But unless the increasing use of cabs is carefully managed, cab traffic will contribute significantly to congestion. According to the Guardian 16/08/2018 there are now 45,000 drivers in the capital working for Uber alone, and the Mayor does not have power to cap the number. Ideally cabs should not be permitted to cruise or otherwise travel needlessly to collect passengers, although there is a case for them to use bus-lanes. If the mayor had the necessary powers, a system of widespread small cab ranks, and a fleet of licensed radio-controlled cabs, centrally managed by an optimising algorithm, could ensure an efficient cab service that contributed minimally to congestion. In the opinion of the author the best way forward would be for TfL to have this management role, with license fees potentially providing a source of direct subsidy for the higher passenger volume “standard class” bus services.

Management of retail delivery traffic

Londoners are increasingly shopping on-line from home, with next-day or same-day delivery (and often return) of purchases, to home or workplace by courier, and consequent reduced demand for bus services to shopping centres. In another context this exponentially growing habit is called “the death of the high street”. The volume of courier cars and vans on London streets must already be making a significant contribution to traffic congestion- and “we ain’t seen nothin’ yet”! How to control it without overmuch reducing end-user benefit?

On-line retailers (Amazon et al) have their warehouses outside London and transport Londoners’ purchases to distribution points within London where they are transferred to couriers for delivery. From the viewpoint of road-usage efficiency, with multiple on-line retailers and multiple courier companies, there is much journey duplication: needless traffic- and some similarity to the cab traffic management problem just discussed.

Centralised management, like the solution proposed for cab traffic, seems necessary to overcome journey duplication, and the Mayor needs the powers to impose this.

There is also some similarity to Royal Mail’s situation, who are of course one of the courier companies: mostly delivering smaller and lighter than average items. Royal Mail’s couriers are postmen pushing carts full of letters and packets along the footpaths. Retailers’ own couriers’ deliveries tend to be spaced out, and powered carts would be more appropriate. If these used the footpaths, as disabled and baby buggies do, and cycle paths, potential congestion increase could be transferred from the roadway to where it might be more readily absorbed.

Electric cars are displacing diesel and petrol driven cars

Electric cars have lower running costs- because they are more efficient and because electricity is cheaper (there is no excise duty or VAT). Charging using off-peak electricity is especially economical. These factors will surely prompt more motorists- perhaps especially commuters- onto London’s roads. How can this source of additional congestion be countered- unless by road space charging and additional priority for buses?

Importance of data

Private cars, cabs, and delivery vehicles have been highlighted above as a sources of bus-service impeding congestion. Detailed analysis of static and dynamic congestion causes would allow a fuller treatment, with quantitative attribution of the characteristic contributions of all vehicular traffic categories to delays in bus services and development of effective measures to protect and improve London’s Bus Service.

Peter Osmon FIET

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‘Driverless cars: on a road to nowhere’

We are very pleased to announce that Christian Wolmar will be joining us once again at a special event on Friday 9th February 2018.

Driverless cars: on a road to nowhere’ is the title of Christian’s latest book, and Christian will be speaking about this from 6pm at The Gallery, 75 Cowcross Street, EC1M 6EL. The venue is close to Farringdon station.

If you would like to attend the event, and join the discussion, it would be useful if you could let Chris Barker, Secretary of the London Group, know as places are limited. Full details, including how to contact Chris, are provided in the flyer below (which is also available as a pdf here).

Flyer for Christian Wolmar event 'Driverless cars: on a road to nowhere'

 

 

TfL and DfT partnership for a joined-up London rail network

A week after the publication of the Centre for London’s report Turning south London Orange: reforming rail to support growth, the secretary of State for Transport, Patrick McLoughlin, and the Mayor of London, Boris Johnson, announced a new approach to the delivery of rail services in London and the south east.

In an announcement on 21 January 2016, the Department for Transport (DfT) and Transport for London (TfL) set out a commitment to improve capacity and service levels across the region’s rail network. Essentially, the DfT and TfL will work together to create a more joined-up London rail network with more frequent services and increased capacity.

The proposals are set out in a prospectus to accompany a consultation (open until 18 March 2016). Details are provided at: A new approach to rail passenger services in London and the south east.

v1: 7.02.2016

Reforming suburban rail

On the 14 January 2016, the Centre for London published a new report “Turning south London Orange: reforming suburban rail to support London’s next wave of growth”.

The press release read: “South London’s transport network is over-crowed and congested. By 2025, the population is set to grow by 270,000 and the pressure on rail services will intensify. The solution? Upgrade south London’s rail network into the Overground, by devolving rail services to Transport for London”.

Details can be found at the Centre for London’s website in Turning south London Orange: Reforming Suburban Rail to support London’s next wave of growth, where you can also download the the report.

v1: 7.02.2016

Archway Gyratory Removal

REMOVAL OF THE A1-A400 ARCHWAY GYRATORY IN TFL ROADS TASK FORCE PROGRAMME

By John MacBryde

The Archway Gyratory is one of the 30-odd (very odd) gyratories which have been identified in the Transport for London (TfL) programme for examination and possible early removal. “The Roads Task Force, a key election pledge by the Mayor, is looking at how TfL and the boroughs could redesign gyratories…and continue to make roads safer for all users. It is also looking at how the road network could better serve local communities.” [GLA Press Release]

Aerial view of Archway Gyratory (1963)
AERIAL VIEW [1963] ARCHWAY GYRATORY [GOOGLE EARTH]
This “squareabout” junction was conceived by the London County Council in 1963 as part of the Archway Tower redevelopment scheme. It was intended to create the southern end of the then projected A1(T) dualling as far north as the A1-A1000 Wellington Junction, the northern part being the responsibility of the Middlesex CC, beyond the historic Archway Bridge. Only the short 6-lane widening was carried out by the LCC in 1963-64. The northern (1500 m) section was left as a 9 m single carriageway since MCC and the MoT were unable to agree a detailed scheme or finance.

Enter the late Transport Minister Marples. Being aggrieved by his recent M1 motorway ending up at the end of an unimproved A1(T) road in North London, he launched one of his more “juicy” one-way schemes of the 1960s. This created a de facto dual carriageway through Highgate by twinning the existing A1 road with the relatively minor B519 up Highgate and North Hill. Cue outrage by the wealthy burghers of Highgate Village who (largely) stopped it all happening.

The great irony, clearly lost on Marples, was that the Archway Road was conceived in 1820 as a bypass to Highgate Hill ! Marples megalomania required several satellite one-way systems to the north, south, east and west of the diamond shape mega-scheme in the middle. The damaging Highgate Village one-way lasted from 1963-93, ie until the formal DETR abandonment of the A1 dualling.

This dualling was the subject of two near-riotous public inquiries in the 1970s. Only two of the satellite gyratories, ie the Wellington A1-A1000 intersection to the north-west and the Archway A1-A400 junction to the south-east, survive to the present time. The latter is the subject of investigation by TfL for possible abandonment (as is also the Wellington Gyratory). A possible solution, prepared by the London Group of the Campaign for Better Transport (CBT) and basically derived from an earlier scheme of the local Better Archway Forum (BAF) is shown on the diagram (right).

DIAGRAM OF REVISED [TWO-WAY] LAYOUT @ 1:2000 SCALE
DIAGRAM OF REVISED [TWO-WAY] LAYOUT @ 1:2000 SCALE
Key to Diagram:

Outbound Traffic Lanes shown in WHITE

Inbound Traffic Lanes shown in BLACK

Kerbside [24h] Bus Lanes shown in RED

This effectively exploits the 3-4 lane capacity of the legs of the “squareabout” by reverting two of them (NE & SE) to two-way general traffic and two of them (NW & SW) to predominantly bus-priority “transit malls” (to use the US terminology) with limited [20 mph] access and egress for B519 traffic up and down Highgate Hill. The carriageway space outside Highgate Underground could thus serve as unified boarding and interchange area for the several LT bus routes passing through or terminating at Archway. This would be consistent with its old [1976] GLDP status as “A Major Interchange

The main objection to the revised scheme, as traffic engineers will be very quick to point out, is that there is “negative reserve capacity” compared with current peak hour flows. In other words, the same number of vehicles cannot negotiate the new layout. However, if throughput is calculated in terms of persons per hour (pers/h) as opposed to vehicles per hour (veh/h) there will probably be rough equivalence or even surplus capacity, given very much higher bus occupancy. Moreover, it would be eminently possible to speed bus movements by dint of virtually continuous kerbside bus lanes which would also act as de facto safer cycle lanes through the currently hazardous gyratory layout; two of the key issues and objectives set out in the 2012 Roads Task Force Report and its Proposals

The various arms of the former gyratory would thus conform to four of the nine individual categories of street (as defined in the 3×3 (“Tool Box”) matrix in the Roads Task Force Report). These might be characterised as follows (in all cases they should be subject to the current local (Islington) 20 mph speed limit).

NE:   Archway Road Directional lane management? B3 CITY STREET
SE:   St Johns Way Asymmetrical 3-lane layout C1 LOCAL STREET
SW: Highgate Hill Interchange + raised surface? C2 TOWN SQUARE
NW:Tollhouse Way Asymmetrical incl 2 bus lanes C3 CITY PLACE

© 2014 John MacBryde DA(Edin) DipTP(UCL) ARIBA MRTPI MCILT

An update on the 2050 London Infrastructure Plan

The Mayor launched a three-month consultation on his 2050 London Infrastructure Plan on 30th July. The Plan is the first attempt to set out the full range of infrastructure requirements for the capital over the next half century, during which time the population of London is forecast to increase by thirty seven per cent to more than 11 million people.

Isabel Dedring, Deputy Mayor for Transport, will present an update on the plan’s progress to the London Group of the Campaign for Better Transport at City Hall on Wednesday, 22nd October at 4pm.

If you would like to attend, please let us know in advance. Full details of how to do this are provided on the attached poster.

IsabelDedring_PublicityPoster_October2014

The group exists to campaign for sustainable transport solutions in London and to support the work of the campaign nationally