MMS Infrastructure charging: seminar summary pages

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In October 2000 GO-East commissioned a consortium led by Mott Macdonald to undertake the London to Ipswich Multi modal Study (LOIS). The study is investigating movement by all modes over a 30 year period for an area encompassing Stansted, the north east sector of the M25, the Thames Gateway area and Southend, the ports of Harwich and Felixstowe, and Ipswich to the north. The M11 bounds the west side of the study area. The study is required to take on board potential development at Shellhaven and Stansted, as well as the existing ports, and also consider the effect of a potential Lower Thames Crossing. Because of the close proximity to London the strategic modelling platform utilises the LASER land use model also used for the ORBIT study, and preliminary network information was extracted from the Orbit highway model Naomi for part of the LOIS detailed area model.

Existing Demands

The study has identified 10 sub-corridors with the area which reflect the main current demand for movement. Major north south movements in the London Ipswich corridor are carried on the A12 and by rail into Liverpool Street Station (104,000 ppd). The Southend - London corridor is served by the A127, the A13 and rail services into Fenchurch St Station (30,000 ppd). The A120 serves as the main east west corridor for movement with no rail service connecting to the west side of the area. The A130 corridor carries east west and north south movement and again has no parallel rail service.

Analysis of movements have identified that some 50 percent of road traffic is for journeys to work, with origins and destinations of traffic on the M25 and the south section of the A12 widely dispersed. With average flows of over 70,000 vehicles per day sections of the A12 frequently experience heavy congestion. As well as north south movements, the lack of public transport to meet demand in orbital directions, and providing connectivity to the west side of the area is seen as a key issue. Rail passenger movements are constrained by track and station capacity at the south end of the corridor, with rail freight movements also constrained by the North London Line, the Ipswich tunnel, and capacity on the Felixstowe to Nuneaton line at the northern end of the area.

Assessment of Policy Measures including RUC.

Because of the major interaction between movements in the A12 corridor and the M25 and other routes to the south, the effect of policy measures for the area are primarily being assessed using LASER in conjunction with the Orbit study. Road User Charging would increase the cost of travel on tolled routes and the impacts will depend on various factors such as the use made of revenue raised, the effect of charging on traffic flow and journey speed and the effects of traffic or travel diverted elsewhere. Within the southern section of the A12 corridor the opportunities to provide additional highway capacity, either on or off line, are extremely constrained by existing development and the limited opportunities for connection to the M25.

There are many factors which will influence a driver's decision whether to consider alternatives and divert or continue to use a tolled road. The understanding of these factors and their relative importance is essential if the effects of congestion charges or tolls on traffic flows, accident levels, environmental issues and financial benefits are to be properly measured.

Thus infrastructure charging within the LOIS study has to consider how RUC on the M25 and the routes to the south interacts with demand on the A12, A13, and other road and rail routes in the area. The impacts of possible tolling and infrastructure charging to be tested within the ORBIT study on the M25 will have a major impact on A12 traffic and assumptions within the LOIS model in respect of RUC are thus consistent with that of ORBIT.

The assessments within Orbit included a review of a wide range of demand management mechanisms and concluded that the most promising strategy for reducing traffic levels and managing demand through infrastructure charging on the M25 (and including the southern section of the A12) is likely to be as follows:

  • Apply urban congestion charging over the whole of London and the urban areas outside the M25 extending over 50 km from central London (ie possibly extending to include Basildon and to the south of Chelmsford)
  • Apply ramp metering or charge tolls for entry to the M25 and southern end of the A12 at levels not so much to reduce traffic levels on the motorway but more to 'lock in' the effects of other measures (that is to control the amount of traffic on the M25 which might be induced by the improved levels of service)
  • Provide high occupancy vehicle lanes to bypass ramp metering or toll charging on entry to the M25, and elsewhere as necessary, to support initiatives such as car poling, and bus based park and ride services.
  • consider carefully the case for limiting further development in the vicinity of the M25 junctions and A12 junctions.

The main RUC scheme components scheduled to be examined using LASER thus include;

  • charging over area extending 50 km from central London
  • a general area-wide charge of 20 p/km (subject to confirmation) with supplement of 3p/km on M25 other motorways and principal trunk roads applied over the day and constant for all vehicle types
  • charges halved in Thames Gateway and other regeneration areas

Other area-wide charge levels of 10p/km and 30p/km are due to be considered by ORBIT and a comparison of the effects on movement within the LOIS study area of each of these will be made.

Strategy Options.

Strategies under development within the LOIS study have been progressed further following a series of stakeholder workshops held in Autumn 2001, and comprise a do-minimum, high public transport and a high road theme. The effect of complimentary policy measures (ie with a single assumed RUC scheme and a limited range of possible variations to this) will thus be considered. Behavioural issues including measures designed to influence mode choice including flexible/staggered working hours and teleworking will be considered as part of a sensitivity test in conjunction with earlier research undertaken by Halcrow for DTLR. Underlying all strategies is the need to make best use of the existing infrastructure, reduce the demand for movement alongside traffic management measures, provide alternatives modes to the car, and provide for better management of freight movement. The high public transport strategy thus includes new heavy rail corridors, and high road strategy considers the effect of new highway infrastructure, with measures to limit induced traffic.

LASER, Land use Transport Model.

A land use / transport interaction model developed by MEAP is being used (LASER). This has the following features of relevance here:

  • It operates at circa. 150 zones for the LOIS study.
  • It contains all the important reactions of travellers to charging except time of day choice
  • The locations of manufacturing and strategic financial and business employment are input and treated as fixed, although the locations of a large part of the retail and education employment are modelled
  • Household location is influenced by employment location
  • The demand segmentation is extensive but demand segments are aggregated prior to assignment
  • The road traffic assignment model uses speed / flow relationships to effect capacity restraint, although the network is detailed and commensurate with the NAOMI and LOIS zone systems.

The model is the only one available with most of the responses required for testing congestion and motorway charging which is currently available to the LOIS and Orbit teams.

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