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Car parks are an essential piece of infrastructure associated with the road networks, yet\ud commonly available traffic assignment models do not to explicitly integrate them into the\ud modelling process. This research attempts to integrate the choice of car parks in urban areas\ud into the travellers’ route choice and incorporates both the route and car park choice in a joint\ud modelling framework of traffic assignment based on equilibrium approach. This paper\ud illustrates the implementation of the model in a commonly used standard suite of traffic\ud assignment software. The proposed method considers multiple user classes - commuter and\ud non-commuter flows, and involves modelling the demand for short stay and long stay car\ud parks over multiple departure periods. A special search time delay function has been\ud developed to represent the disutility in searching for a place in a car park, which is integrated\ud further into the function of generalised cost of travel. This technique has been successfully\ud applied to study the choice of car parks in the case of a simple hypothetical network. Another\ud larger numerical example illustrates the case of managing the demand between two car parks\ud in Leeds, England.

Integration as a principle in urban transport policy is frequently advocated but rarely defined. We suggest a range of types of integration, and highlight the problems in developing an effective integrated strategy, given the number of variables involved. We argue that integration should be designed to serve agreed objectives of transport policy, rather than being an objective in its own right.\ud We then consider the principles for designing an effective integrated strategy. We define the concept of synergy, which is often advocated as a benefit of integration, and discuss whether it, and other aggregation benefits short of true synergy, are achievable. We then consider the alternative approach of using integration to overcome barriers, an approach which is likely to be in conflict with pursuit of synergy, but more likely to lead to readily implemented strategies.\ud We then review a number of examples where these principles have been applied, and investigate them to assess whether synergy has been demonstrated. Generally we find little evidence of synergy in outcome indicators. We conclude with some more general guidance on approaches to integration.

This paper describes local government decision-making in transport in three areas of the UK, London, West Yorkshire and Edinburgh, in which major changes in local government decision-making structures have taken place over the last decade, and between which arrangements are now very different. The research discusses whether institutional change has had a beneficial or adverse effect, and whether any of the current structures provides a more effective framework for policy development and implementation. The results show that although the sites share a broadly common set of objectives there are differences in devolved responsibilities and in the extent to which various policy options are within the control of the bodies charged with transport policy delivery. The existence of several tiers of government, coupled with the many interactions required between these public sector bodies and the predominantly private sector public transport operators appears to create extra transactional barriers and impedes the implementation of the most effective measures for cutting congestion. There is, however, a compelling argument for the presence of an overarching tier of government to organise travel over a spatial scale compatible with that of major commuter patterns. The extent to which such arrangements currently appear to work is a function of the range of powers and the funding levels afforded to the co-ordinating organisation.

The aim of the paper is to provide a number of recommendations for use of transport and land use planning models in the formulation of local transport plans. It is based on a study of Local Transport Plans (LTPs) in England. LTPs are required by central government (Department for Transport) as part of its process of allocating funds to local authorities. The first round of LTPs (for which 85 authorities submitted plans) was carried out in 1999-2000 and the next round will be required in 2005. Authorities are also required to produce Annual Progress Reports (APRs) summarising the progress made towards meeting the objectives laid out in the LTP. The research was carried out in two stages, the first being a review of current guidance, publicly available Local Transport Plans and other relevant material, the second being a series of case study interviews with five local authorities. From these two processes a number of recommendations on modelling requirements and use of models were put forward classified by the size of the local authority

The paper reports on the development of UK transport targets for CO2 emissions for 2050. Five key studies containing future carbon emissions scenarios for the UK were used to establish targets for overall reductions in emissions to achieve stabilisation at 550 ppm and 450 ppm of atmospheric CO2. Two approaches were used to consider the proportion of total emissions that would be attributable to transport in the future: 26% of total emissions as now and an increase to 41% of total emissions in line with forecasts. The overall targets and expected contributions from transport were used to derive target emissions for the transport sector to be achieved by 2050, which ranged from 8.2 MtC to 25.8 MtC. Even the weakest of these targets represents a considerable reduction from current emissions levels.

This paper describes a method for devising transport strategies that makes iterative use of transport models to find the optimal levels of pre-defined transport measures. It gives the results from using this method in nine European cities. At the heart of the procedure lies the definition of objective functions which encapsulate policy-makers’ objectives with respect to economic efficiency and sustainability. These objective functions include a number of significant parameters and the paper examines the sensitivity of the results to changes in the values of these parameters. The parameters concerned are: the level of shadow price used with regard to public sector financial surplus and deficit; the trade-off between the perspectives of the present generation and a future generation (of importance to issues of sustainability); the trade-off between internal benefits/costs and external (environmental) benefits/costs; and the level of user benefits that can be “value captured” in the sense of raising additional finance for transport policies. Full sets of results are given for these sensitivity tests, and a number of practical transport policy conclusions are made.

The material in this Working Paper was generated as input to DETR's Guidance on the Methodology for Multi Modal Studies (GOMMMS). DETR subsequently decided only to provide summary information on transport policy measures, and to leave the consultants involved in individual multi modal studies to make their own assessment of individual policy measures in the context of specific study areas. It has been decided to make this fuller document available as a reference source. The purpose of the review of policy measures was to provide summary information on the range of policy measures available, experience of their use and, based on past studies, their potential contribution to the range of policy objectives specified for GOMMMS. The review was based on an earlier one included in the Institution of Highways and Transportation's Guidelines on Developing Urban Transport Strategies (1996). This material was updated using references published since 1996 and expanded to cover policy measures relevant in inter-urban areas. It had been intended to circulate it for comment before publishing a revised version. However, DETR decided to use an abridged version before this consultation was complete. It should be borne in mind that this document has not, therefore, undergone the peer assessment which had been intended. To avoid unnecessary further work, the material is presented as it had been drafted for the GOMMMS Guidance document. The only modifications have been to change the chapter and paragraph numbers, and to remove the cross references to other parts of the Guidance document.

EXECUTIVE SUMMARY\ud \ud This Final Report covers the results of the EU-funded research project FATIMA (Financial Assistance for Transport Integration in Metropolitan Areas) which had the following objectives: \ud \ud (i) to identify the benefits to the private sector of optimal urban transport strategies, and the potential for obtaining private sector funding to reflect those benefits; \ud \ud (ii) to determine the differences between strategies optimised using public funds and those optimised within the constraints imposed by private funding initiatives; \ud \ud (iii) to propose mechanisms by which private sector funding can be provided so as to achieve appropriately optimal transport strategies while maintaining quality of operation; and \ud \ud (iv) to use the results to provide more general guidance on the role of private sector funding for urban transport in the EU. \ud \ud The project adopted an approach which involved the application of the same study method to nine cities, chosen to reflect a range of urban transport policy contexts in Europe: Edinburgh, Eisenstadt, Helsinki, Merseyside, Oslo, Salerno, Torino, Tromsø and Vienna. This method involved specifying appropriate policy objective functions against which transport strategies could be assessed, and finding the specific strategy that optimised each of these functions. The objective functions covered a range of differing regimes with respect to constraints on public finance and the involvement of the private sector. \ud \ud \ud It was found that, in a majority of the case study cities, optimal socio-economic policies could be funded by road pricing or increased parking charges, considered over a 30 year time horizon. Such measures would typically be used to make it feasible to increase public transport frequency levels or decrease public transport fares. In general it was found to be important that the city transport planning authority had complete control over all transport measures, affecting both private and public transport. \ud \ud However, such strategies are likely to require significant levels of investment and, given current attitudes towards constraints on public spending, it might be politically awkward for the public sector to raise such finance. There is thus a potentially useful role for private finance to be used to help overcome such (short term) financing problems. However, it must be appreciated that the private sector will expect to make a profit on such investment. In cities where optimal policies are funded by travellers, the private sector can be reimbursed by travellers. In cities where it is unfeasible for travellers to fund all the costs of optimal policies, it will be necessary for the private sector to be reimbursed from public funds (raised from taxes). An important issue here is that the use of private finance should not be allowed to replace optimal policies with sub-optimal policies. \ud \ud \ud Whether or not the private sector is involved in financing a strategy, there may be interest in private sector operation of the public transport service. However, evidence on the scale of benefits or losses from such operation is unclear. If, though, a city authority decides that private operation is beneficial, it should use, where legally possible, a franchising model in which it specifies optimal public transport service levels and fares. On the other hand, if a deregulation model is required (in order to comply with national law), private operators should not be given complete freedom to determine the operating conditions which meet their profitability target, even if the level of profitability is itself constrained as a result. There are typically a number of combinations (e.g. of fares and frequency) which achieve a given level of profitability, and not all will be equally effective in terms of public policy objectives.

The final report of project FATIMA is presented in two parts. Part 1 contains a summary of the FATIMA method and sets out the key recommendations in terms of policies and optimisation methodology from both project OPTIMA and project FATIMA. Part 1 is thus directed particularly towards policy makers. Part 2 contains the details of the methodology, including the formulation of the objective functions, the optimisation process, the resulting optimal strategies under the various objective function regimes and a summary of the feasibility and acceptability of the optimal strategies based on consultations with the city authorities. This part is thus mainly aimed at the professional in transport planning and modelling.

Very few transport studies have been able to demonstrate that transport policy measures alone can improve sustainability by reducing fuel consumption and emissions below existing levels. There is therefore an increasing interest in the use of coordinated transport-land use policies, but a lack of understanding of relevant relationships. This research sought to obtain greater insight into these relationships. The main objectives were: (i) to increase our understanding of the impact of accessibility and environmental quality on individuals’ and firms’ location decisions; (ii) to use the findings of (i) to enhance a newly developed strategic transport and land use interaction model; (iii) to use the enhanced model to assess the implications for urban sustainability of the impact of transport policy on location choice; and (iv) to use the enhanced model to assess the relative performance of different combinations of transport and land use strategy. \ud \ud There were two main strands to the work. The first involved the use of a newly developed strategic transport-land use model DELTA/START to test the effects of a range of values for environmental and accessibility coefficients. The tests were based on Edinburgh, and included several combinations of road pricing, fares reductions and light rail, and an alternative land use strategy. The second strand involved a literature review and survey work undertaken in Edinburgh using a stated preference approach to identify values for environmental indicators and accessibility to feed into the model. \ud The survey work of households and businesses was successful in producing values for environmental quality and accessibility. We found that changes in air quality were valued more highly than corresponding changes in noise levels. The survey also revealed some interesting issues that merit further investigation: deteriorations in environmental quality were valued more highly than improvements, there was a greater resistance to increases in council tax beyond current levels than up to current levels and valuations were higher where conditions were worse. \ud \ud The transport strategies were predicted to induce considerable shifts in activity, with city centre populations increasing by up to 20%. However, these substantial changes in activity had relatively small impacts on the transport indicators. The results for the alternative land use scenario showed similar effects. Generally it appears, from the tests involving the strategic transport model that the effects on transport indicators of land use changes, whether induced through transport strategies or imposed through land use planning, are an order of magnitude lower than those of the transport strategies themselves. This is an important policy result since it calls into question how much can be achieved by pursuing coordinated land use and transport strategies. \ud

The overall objectives of Project OPTIMA were: \ud \ud (i) to identify optimal urban transport and land use strategies for a range of urban areas within the EU; \ud \ud (ii) to compare the strategies which are specified as optimal in different cities, and to assess the reasons for these differences; \ud \ud (iii) to assess the acceptability and feasibility of implementation of these strategies both in nine case study cities (Edinburgh, Merseyside, Vienna, Eisenstadt, Tromsø, Oslo, Helsinki, Torino and Salerno) and more widely in the EU; and \ud \ud (iv) to use the results to provide more general guidance on urban transport policy within the EU.

This Working Paper presents the results of tests of various transport policies which could potentially have a major impact on private car travel and hence gain environmental benefits at a national level. The forecasting methodology was to take OPCS population forecasts for year 2006 in 28 age/sex/area type categories, predict the car available percentage of person in each category in 2006, and then predict trip mileage growth (by three mode types for the 28 categories each subdivided into car available and car non-availahle. For the latter two predications, NTS data for 1985/6 and 1991/3 were compared and projected forward with various adjustments. The effect of individual transport policies on trip rates for individual cells was determined from results derived from other studies, coupled with a consideration of economic theory. Of the tests considered, only the tripling of fuel prices for private mode transport was ahle to hold private mode mileage in 2006 at ahout its 1992 level.

This paper describes the background and methodology employed in research funded by EPSRC to assess the effect of individual traffic control measures, both in isolation and in combination upon urban arterials. The aim of the project was to test the transferability of the techniques developed in a DRIVE II project, PRIMAVERA, to a range of different types of urban corridor. Measures can be classed into three broad categories: Congestion Management, Public Transport Priority and Traffic Calming. The scope of these measures is wide, some operating at a junction level whilst others affect the whole network. Measures from these areas are applied to a sophisticated microsimulation model of four urban arterial corridors: three in Leeds and one in Leicester. The effects of the application of individual and integrated measures are assessed in terms of their efficiency, environmental and safety impacts using a form of Multi-Criteria Analysis. Travel time and other monetary costs are also taken into consideration. This paper describes the study of two neighbouring arterials to the west of Leeds, the Otley and Kirkstall Roads. These arterials have been considered together since they are geographically close to each other. The Otley Road is the main arterial to the north west of Leeds City Centre, linking the Outer Ring Road to the Centre and is approximately 5km in length. The Kirkstall Road is to the south of the Otley Road, running west to east. The section of Kirkstall Road chosen for inclusion in this combined corridor is 3.5 km in length. The land use surrounding each corridor is primarily residential although near the city centre on the Kirkstall Road there are light industrial units. A popular district shopping centre exists halfway along the Otley Road.

A series of hypothetical corridors have been simulated, representing a range of junction spacings, capacity distribution, availability of parallel routes, bus flows and routing patterns. These have been used to test a range of traffic management measures designed to increase capacity, improve public transport operations and calm traffic. All measures have been assessed in terms of their impact on travel costs and conclusions have been drawn in terms of the appropriateness of different measures in differing contexts.

This paper describes the background and methodology employed in research funded by EPSRC to assess the effect of individual traffic control measures on urban arterials, both in isolation and in combination. The aim of the project was to test the transferability of the techniques developed in a DRIVE II project, PRIMAVERA, to a range of different types of urban corridor. Measures have been classed into three broad categories: Congestion Management, Public Transport Priority and Traffic Calming. The scope of these measures is wide, some operating at a junction level whilst others have an impact over a whole corridor. Measures from these categories are applied in a sophisticated microsimulation model of a series of hypothetical networks and four urban arterial corridors: three in Leeds and one in Leicester. The effects of the application of individual and integrated measures are assessed in terms of their efficiency, environmental and safety impacts using a form of Multi-Criteria Analysis. Travel time and other monetary costs are also taken into consideration. Whilst these results are of interest to local planners in the operation of each of the arterial corridors studied, a wider insight into the operation of urban arterials can be drawn from this study leading to more efficient control of the available road space.

This paper describes the background and methodology employed in research funded by EPSRC to assess the effect of individual traffic control measures, both in isolation and in combination upon urban arterials. The aim of the project was to test the transferability of the techniques developed in a DRIVE II project, PRIMAVERA, to a range of different types of urban corridor. The techniques concerned can be classed into three broad categories: Congestion Management, Public Transport Priority and Traffic Calming. The scope of these measures is wide, some operating at a junction level whilst others concentrate on the efficient use of road space. Measures from these areas are applied to a sophisticated microsimulation model of four urban arterial corridors: three in Leeds and one in Leicester. The effects of the application of individual and integrated measures are assessed in terms of their efficiency, environmental and safety impacts using a form of Multi-Criteria Analysis. Travel time and other monetary costs are also taken into consideration. This paper reports the results for the A47 Humberstone and Uppingham Roads which form the main arterial route to the east of Leicester.

This paper describes the background and methodology employed in research funded by EPSRC to assess the effect of individual traffic control measures, both in isolation and in combination upon urban arterials. The aim of the project was to test the transferability of the techniques developed in a DRIVE II project, PRIMAVERA, to a range of different types of urban corridor. Measures can be classed into three broad categories: Congestion Management, Public Transport Priority and Traffic Calming. The scope of these measures is wide, some operating at a junction level whilst others affect the whole network. Measures from these areas are applied to a sophisticated microsimulation model of four urban arterial corridors: three in Leeds and one in Leicester. The effects of the application of individual and integrated measures are assessed in terms of their efficiency, environmental and safety impacts using a form of Multi-Criteria Analysis. Travel time and other monetary costs are also taken into consideration. This paper reports the results for the A64 York and A63 Selby Road which are the main arterial routes to the east of Leeds. 1

INTRODUCTION\ud \ud Even with relatively simple model packages and modern computers, it is not feasible to test all combinations of model input variables to see which combination gives the 'best' outcome. Neither is it usually possible to solve the models analytically for the optimum. Consequently, there is a potential role for a methodology which takes as input the results from a relatively small number of runs of the model package and then models the response surface in the region containing the optimum, in such a way that it can be analytically solved for the optimum. This paper will set out such a methodology together with a Case Study.

This working paper is the third in a series relating to the EPSRC funded project, " The definition of capacity in urban road networks : the role of area speed-flow relationships". The paper looks at the sensitivity of the results to the process of modelling blocking-back in NEMIS, for the same 6x6 grid network described by May and Shepherd (1994b). \ud \ud First of all the blocking-back logic implemented in NEMIS is described. This logic was developed by Shepherd (1990) for use on an arterial network with the intention of blocking cross flows at signalised junctions. When implemented on grid networks with high demands and certain turning ratios this logic can lead to gridlock conditions. The logic implemented in NEMIS caused an irrecoverable gridlock condition i.e. once gridlock occurs it cannot be cleared. Although gridlock conditions may exist for short periods of time in the real world driver behaviour and or external factors combine to relieve the condition eventually. The results will be discussed with and without the blocking-back model implemented in NEMIS for matrix B - heavy inbound traffic. \ud \ud This work also revealed some problems with the tracking approach described by May and Shepherd (1994a) and the definition of demand when extended from single link/zone networks to multi-zone networks. One of the main problems was that of overlapping in the space-time domain, the amount of overlap increasing as demand is increased.

INTRODUCTION\ud \ud This evidence, submitted to the Select Committee for its inquiry into Urban Congestion Charging, is based on my research into the subject, and professional involvement in studies of methods for managing the demand for urban travel, over the last twenty years. In the 1970s I was responsible, within the Greater London Council, for their studies of the use of comprehensive parking control, physical restriction of road space, and supplementary licensing (a low technology method of congestion charging) as methods of traffic restraint. At the same time, I was an adviser to the World Bank in its study of Singapore's area licensing scheme which is still the only congestion charging system in operation. In the 1980s I was an adviser to the US Transport Research Board in its investigation of appropriate methods for managing urban traffic, and to The MVA Consultancy in its study of electronic road pricing for Hong Kong. Since 1987 I have been involved, as a director of The MVA Consultancy, in a series of integrated transport studies in London (for the London Planning Advisory Committee), Birmingham, Edinburgh, Bristol and Merseyside, each of which has investigated the role of congestion charging as part of a wider transport strategy. I am currently directing a programme of research, funded by the Engineering and Physical Sciences Research Council, which is assessing the relative impact on urban road networks of different methods of imposing congestion charging, on their own and in combination with traffic signal control and bus priorities. This research has used Cambridge and York as case studies. In addition, I am currently acting as one of the technical advisers to the Department of Transport's study of congestion charging in London. \ud \ud (Continues..)

This working paper is the first in a series relating to the EPSRC funded project, " The Definition of Capacity in Urban Road Networks : The role of Area Speed-Flow Relationships". It defines the measures collected and the methods for data collection in terms of space-time diagrams. The four measures are collected by simulating different levels of demand. Two cases are presented, the first simulates constant demand throughout each simulation period, the second simulates a demand profile which stays uniform as peak demand increases. \ud \ud The paper concentrates on single link models with only one OD pair and only one route. Two equivalent networks are presented. The first represents a single link where the capacity of the link is maintained. The second is a purely hypothetical network where the capacity is reduced to zero as demand increases. This is achieved by a loop configuration so that the departure rate is affected by the queue blocking-back on itself.

This working paper is the second in a series relating to the EPSRC funded project, " The Definition of Capacity in Urban Road Networks : The Role of Area Speed-Flow Relationships". The paper reports on the collection of the four measures described by May and Shepherd (1994) for a 6x6 grid network for various origin destination patterns. \ud \ud The grid is divided into zones. Within each zone the simulated links are defined as either inbound, outbound or orbital in nature and the data is aggregated according to link type and vehicle generation time or period. This form of data aggregation is required by the strategic model START. \ud \ud The aim of this paper is to determine the area speed flow relationships within the zone links and to test whether they are sensitive to changes in OD pattern. Six different OD patterns have been simulated across a similar range of demand.

This working paper reports work indertaken on an EPSRC study, the optimisation of integrated urban transport strategies. It is the fist in a series of papers each reporting work using a different transport model. This paper is concerned with work using PLUTO, a transport model based on a hypothetical city, which can provide model runs quickly and cheaply. \ud \ud PLUTO was used to experiment widely, examining paths towards an optimum when considering discrete policy variables, continuous policy variables and hybrids where several policy variables may be combined to form a strategy. \ud \ud \ud Our search for a method by which to reach an optimum solution uses regression analysis of carefully specified sets of model runs. We find that the use of statistical modelling techniques is extremely useful in pointing the way to an optimum, using only a limited number of model runs. However, care is necessary to ensure that the regression models are interpreted correctly.

This Working Paper extends the study reported in Working Paper 400, which used the MVA START model for London, disaggregated into three income groups for each of car owners and non car owners, to investigate the distributional effects of road pricing in London. At the time of that study, it was not possible to obtain, from the disaggregate model, output on trips, flows and speeds. The further work reported in this Working Paper has involved extending the evaluation procedures to provide output on trips, flows and speeds; assessing the results from the previous study in tms of these indicators, and testing a fourth charging structure. In all, four charging structures were tested. It is concluded that the additional charging structure tested here, with the original LPAC charging structure, but with charging extended to the off peak in inner London, is by far the most effective in terms of overall benefits, and is similar in its distributional effects to the original LPAC structure.

The aim of this research has been to investigate the modelled effects of alternative road user charging systems upon an existing road network using the congested assignment models SATURN and CONTRAM applied to the city of Cambridge. Four road user charging systems which are being considered for practical application have been tested. These are toll cordons, time-based charging, a congestion charging system similar to that proposed in Cambridge and distance-based charging. Tests have been conducted using current morning peak travel demand patterns both with a fixed trip matrix, to isolate rerouteing issues and using the SATURN elastic assignment program, SATEASY, in order to address the effects of charging upon the frequency, timing and distribution of trips. Network impacts have been assessed using a series global indicators, in particular effects on vehicle-km, vehicle-hours and the resulting average network speeds. In addition, results have been obtained for total delay times, cordon crossing flows and revenues generated from charging. These results are presented and their implications discussed.

\ud \ud

This Working Paper presents results obtained using the MVA START model for London, with the primary intention of investigating the distributional impact of road pricing in various forms and at various levels. In order to look at distributional effects the START model had to be 'disaggregated' by income groups - three each for non-car owning and car-owning households. Initially, this allowed us to see the distributional impact of the LPAC Preferred Strategy, mainly involving public transport and traffic management policies. Beyond this we tested three structures (or 'regimes') of road pricing, varying from a complex three cordon plus screenlines structure, to a single Central London cordon. Somewhat surprisingly, the latter was found to be regressive in its application. The structure with the highest benefits, as well as being relatively progressive, was the complex structure of three cordons plus screenlines, with an optimum charge level of 50 pence per cordon crossing, each way but with the outer two cordons being peak only.

This Working Paper is one of a series representing work under a SERC grant on queue management strategies for urban traffic control systems, whose objectives are:- (i)to generalise the strategies developed in an earlier study of queue management; (ii)to develop a computer graphics based representation of queue propagation and management; (iii)to test the strategies' applicability and performance in UK networks; (iv)to investigate their incorporation into standard signal optimisation programs. The study is based on earlier work in Bangkok (May et al, 1988) also funded by SERC, in which queue management measures were developed by trial and error to allow for the fact that queues from downstream junctions frequently blocked upstream junctions and could, as a result, unnecessarily obstruct crossing movements thereby reducing junction capacity and spreading congestion to other areas. The methods developed in that study involved:- (i)predicting the growth and decline of queues from downstream junctions; (ii)estimating the speeds of the starting and stopping waves which determine (i); (iii)identifying the most appropriate stage at the upstream junction in which queues should arrive; (iv)identifying the most appropriate time in that stage during which queues should be present; (v)adjusting the split between stages to allow for loss of throughput in blocked stages; (vi)adjusting the cycle time as necessary in the light of (v). It was steps (iii) and (iv) which involved the greatest element of trial and error, and it was accepted that further work was needed to identify alternative strategies for determining:- (i)during which stage to allow queues to block an upstream junction; (ii)how to adjust the stage timings at that junction to allow for the loss of capacity. This paper reviews these approaches and makes recommendations. It considers first of all, in Section 2, the options at an individual junction. It then considers in Section 3, the application of these options in a range of increasingly complex networks.

In December 1990 we were invited by Birmingham City Council and Centro to submit a proposal for an introductory study of the development of a common investment appraisal for urban transport projects. Many of the issues had arisen during the Birmingham Integrated Transport Study (BITS) in which we were involved, and in the subsequent assessment of light rail schemes of which we have considerable experience. In subsequent discussion, the objectives were identified as being:- (i) to identify, briefly, the weaknesses with existing appraisal techniques; (ii) to develop proposals for common methods for the social cost-benefit appraisal of both urban road and rail schemes which overcome these weaknesses; (iii) to develop complementary and consistent proposals for common methods of financial appraisal of such projects; (iv) to develop proposals for variants of the methods in (ii) and (iii) which are appropriate to schemes of differing complexity and cost; (v) to consider briefly methods of treating externalities, and performance against other public sector goals, which are consistent with those developed under (ii) to (iv) above; (vi) to recommend work to be done in the second phase of the study (beyond March 1991) on the provision of input to such evaluation methods from strategic and mode-specific models, and on the testing of the proposed evaluation methods. Such issues are particularly topical at present, and we have been able to draw, in our study, on experience of:- \ud (i) evaluation methods developed for BITS and subsequent integrated transport studies (MVA) (ii) evaluation of individual light rail and heavy rail investment projects (ITS,MVA); (iii) the recommendations of AMA in "Changing Gear" (iv) advice to IPPR on appraisal methodology (ITS); (v) submissions to the House of Commons enquiry into "Roads for the Future" (ITS); (vi) advice to the National Audit Office (ITS) (vii) involvement in the SACTRA study of urban road appraisal (MVA, ITS)

This study was designed to review the proposals for road user charging in the Randstad, Stockholm, Oslo and Singapore, to determine the intentions for monitoring of each of these proposed schemes, to assess the implications for the development of policy in London, and to identify any opportunities for obtaining experience which would help in clarifying the uncertainties associated with proposals for road pricing in London. The study reviewed the objectives and operational requirements for road pricing in London and the criticisms levelled against such proposals. On this basis it developed a series of requirements for monitoring and information gathering to help clarify the outstanding uncertainties. These were used as a check list for a series of discussions with those responsible for proposals in the case study cities. Discussions indicated that the proposals in most cities had changed markedly in the period since the study was commissioned. These changes, and the resulting nature of the proposals, meant that only the proposals for Stockholm were sufficiently similar to those in London to justify collaborative monitoring. The report recommends that such collaboration be developed. However, both the Randstad and Oslo schemes offer the opportunity for obtaining information on actual or predicted user response, while the Singapore proposals will provide valuable experience of new technology. It is recommended that all of these are pursued. The discussions highlighted several lessons of direct relevance to the development of policy in London. In particular it is seen as important to keep the specification of the measures simple; to pursue extensive consultation with those who might be affected and with all political parties and government bodies who might be involved in policy decisions; to provide clear guidance on the anticipated uses of the revenue: and to develop a system which is implemented flexibly, so that problems can be remedied as they arise. \ud \ud In this context, the role of assessment and monitoring is limited. It should not be used to delay decisions; however, once a commitment is made to proceed, experience from elsewhere will be of value in informing the consultations. A carefully designed monitoring programme will be important in assessing and enhancing a scheme once implemented. It is recommended that the monitoring programme should be based on the requirements identified in this report.