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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 literature on acceptability of road pricing schemes is reviewed, and a number of\ud limitations of that research are identified. In particular, little evidence is found of the\ud differences between users and non-users and the effects of scheme design and level of\ud charge. A stated preference survey was conducted in two UK cities to provide evidence\ud on these issues. Charging was found to be more acceptable to non-users, those who\ud perceived pollution and congestion to be very serious, those who considered current\ud conditions unacceptable, and those who judged road pricing to be effective. It proved\ud possible to identify design combinations, for both cities, which would be voted for by a\ud majority.

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.

This paper is one of a series concerned with the SERC Rolling Programme on\ud fundamental aspects of the performance of dynamic route guidance systems, and more\ud specifically related to that strand of the programme which has been conducted in Berlin,\ud in conjunction with the field trial of dynamic route guidance (LISB). This field trial has\ud provided the opportunity to test methods, developed in an earlier study (May and Bonsall,\ud 1988) for assessing the objective benefits gained by drivers receiving guidance. This paper\ud describes the survey method for that study.\ud A method was developed in which pairs of drivers, one with LISB guidanee and one\ud without, travelled at the same time between the same origins and destinations. One set\ud of journeys were those to and from work performed by participants who had been using\ud LISB for some time, and who were paired with student drivers. The others were off peak\ud journeys in the same corridors, travelled by student drivers in pairs.

A recurring theme in the debate on urban transport policy in the last few years has\ud been the appropriateness of developing Integrated Transport Strategies as a basis\ud for identifying solutions to current and future urban transport problems. Their\ud proponents, including a growing number of local authorities, see them as a means of\ud ensuring that each element of transport policy complements the others. Those who\ud argue against them, and particularly the Department of Transport, have likened\ud them to the gramd and unattainable, blueprints produced by 1960s land use -\ud transport studies. This paper draws on experience with such studies in London,\ud Birmingham and Edinburgh to assess the strengths and weaknesses of the approach\ud now being adopted, to suggest ways in which it might be further developed, and to\ud identify, in the light of experience to date, those elements of policy which might\ud most effectively contribute to the solution of transport problems.

INTRODUCTION \ud \ud 1.1 The growth in demand for travel \ud \ud Over the 20 years hm 1965, National Travel Survey (NTS) data shows a 61% growth in total person - km of travel. More detailed analysis suggests that this is made up roughly as follows:- \ud \ud due to increased population 4% \ud \ud due to more journeys 22% \ud \ud \ud due to longer journeys 35% \ud \ud This implies that around 60% of the growth in travel has been due to people travelling further, rather than making more journeys. \ud \ud It is interesting to note, too, that the same phenomenon occurs even in the most congested areas. Between 1975 and 1985, NTS shows an 11% growth in person -km by London residents, at a time when population fell by 5%. In this case, the growth is made up roughly as follows:- \ud \ud due to lost population -5%\ud \ud due to more journeys 4%\ud \ud due to longer journeys 12%\ud \ud It is of course difficult to estimate the extent to which future growth in travel will be generated by longer journeys. The NRTF, which predicts a growth in car-km of between 120% and 180% between 1985 and 2025, is not based on a procedure which enables the effects of journey making and journey length to be separated. However, it is worth noting that if the same pattern were to exist at a national level in future, the predicted growth in car travel due to longer journeys could be equivalent to between 75% and 100% of today's car travel. It seems appropriate to ask whether it is a wise use of scarce resources to provide the infrastructure and energy needed to enable people to carry out their activities further from home. \ud (Continues...)

This report describes a study conducted for Sheffield City\ud Council to obtain pedestriansr reactions to the quality and\ud acceptability of footways of different construction in\ud different conditions, and to assess pedestriansr preferences\ud for different types of footway construction. The results are\ud intended to aid the Council in identifying priorities for the\ud maintenance of existing footways, and preferred surfaces for\ud new or reconstructed footways. The study involved four\ud stages; a new survey to identify footway characteristics of\ud concern to pedestrians; interviews and objective measurements\ud at a total of 13 sites; interviews at a set of eight purpose\ud built trial sites; and analysis and interpretation of the\ud results.

1.1.1 Any new road, road improvement or traffic management\ud scheme could affect pedestrian journeys in its locality or\ud elsewhere. Some journeys may be affected directly, with\ud severance caused where the new road or road improvement cuts\ud across a pedestrian route, others may be affected indirectly with\ud a new road causing changes in traffic levels elsewhere. To\ud enable effects on pedestrians to be given proper weight when\ud decisions are taken, techniques are required that forecast the\ud effects of the scheme on the number and quality of pedestrian\ud journeys. This is particularly true in urban areas, since\ud effects on pedestrians may be one of the main benefits or\ud disbenefits of measures to relieve urban traffic.\ud \ud (Continues..)\ud

This working paper describes the results and conclusions drawn\ud from experiments in traffic control carried out in Bangkok,\ud Thailand, during a study of the control of highly saturated\ud networks.\ud Other papers in the series are WP 248 (Survey Design and Data\ud Collection)\ud WP 249 (Development of Signal\ud Timings)\ud and WP 250 (Incidents and their\ud Management)\ud This study formed a follow-up to an earlier study reported in\ud WP 220, WP 221 and WP 222.\ud

This working paper is one of a series (WP 252, 253, 254, 255, 274, 275), describing work undertaken under contract to TRRL investigating design guidance for pedestrian areas and footways to satisfy the needs of disabled and elderly people. This working paper reports on fieldwork conducted with disabled people in Leeds to investigate movement distances; assessments of surface conditions including gaps, undulation, gradients, camber and friction; and assessments of bus shelter seating.

This working paper describes a study of the variability of journey times of a panel of fifteen commuters using one north London radial corridor, over a total of seven weeks in the spring and summer of 1987. The objectives were to gain preliminary information on the extent of journey time variability and on the commuters* perception of and responses to the variability they experienced. The procedure for selecting the panel and contacting them is described, together with the data collection method, which consisted principally of panellists using tape recorders in their cars to record the time at which fixed points along the route were passed on each day's journey to work. Early or late arrival and its consequences in relation to the day's tasks were recorded at the destination. Analyses are presented of the distributions of times of complete and partial journeys, of the relationship between journey duration and variability and of the effects of diversion in response to perceived traffic conditions. The safety margins needed to ensure given percentages of punctual arrivals were estimated and contrasted with those from previous studies. Further analyses are presented indicating the general unimportance of punctuality for these panellists, the effects of significant lateness when it did occur, and of the panellists' ability to predict their arrival times in advance. A study of highway link travel time variability and its causes was also carried out for cars at the a same time in the same corridor. The methodology, surveys and data processing of this parallel study are set out in ITS Working - Paper 278, and the results and analysis in ITS Working Paper 279.

Firms in inner areas of Leeds and London were surveyed to determine the type, extent and severity of their transport problems. The problems were compared with tlose of firms in outer control areas of both cities. The important inner area problems were: congestion and delays on the journey to work, on business and visitor trips, and on commercial vehicle trips; inadequate on-site and on-street parking at the firm and at the destination of business trips; public transport difficulties for the journey to work; on-site delays for commercial vehicles; and on-street loading.Altiough firms in all areas experienced similar types of problem, the effect of congestion and parking WaS more severe in the inner areas, and as expected problems were more severe in London than in the corresponding area of Leeds. Solutions applicable to the inner areas are therefore likely to be appropriate elsewhere. The most common effect of problems was lost time. There were also cases of reduced efficiency, lost business, vehicle scheduling difficulties and staffing implications such as turnover and recruitment and staff dissatisfaction. Management had difficulty costing the effects of problems; however, when estimates were made the costs incurred were often considerable. Problems were, for the most part, local or site specific, and solutions are likely to be found within the study areas or at individual firms. However, in the case of congestion and of parking availability away from the firm the problems are more widespread, suggesting that solutions need to extend beyond the study areas.

1.1.1 Any new road, road improvement or traffic management\ud scheme could affect pedestrian journeys in its locality or\ud elsewhere. Some journeys may be affected directly, with\ud severance caused where the new road or road improvement cuts\ud across a pedestrian route, others may be affected indirectly with\ud a new road causing changes in traffic levels elsewhere. To\ud enable effects on pedestrians to be given proper weight when\ud decisions are taken, techniques are required that forecast the\ud effects of the scheme on the number and quality of pedestrian\ud journeys. This is particularly true in urban areas, since\ud effects on pedestrians may be one of the main benefits or\ud disbenefits of measures to relieve urban traffic.\ud \ud (Continues..)

BACKGROUND\ud \ud This study was commissioned by the Civic Trust to identify new approaches to traffic management solutions for Sowerby Bridge. The objective of the overall study was to identify low cost, innovative solutions to problems created by high volumes of traffic using the A58. This road is the main shopping street in Sowerby Bridge. In our brief it was stressed that any new road construction, such as a by-pass, was not a feasible or acceptable solution due to the severe vertical gradients surrounding Sowerby Bridge. \ud \ud The town is on the brink of a major programme of regeneration. A nationally important canoe slalom course has been created, the riverside mill area fronting onto the River Calder is being developed for commercial and leisure use, and there is a proposal to reopen the Rochdale Canal. In view of this it is essential to ensure that traffic on the A58 is managed so as to minimise its effect on the environment and trade, without adversely affecting local access. In writing our report we have separated the problem and solution identification stages. The solution identification stage is reported in Working Paper 263 (Hopkinson et al 1988b). The final stage of our study, which involves presenting our final solutions back to the users of Sowerby Bridge for comment, is to be reported in a forthcoming report, WP 265 (Hopkinson et al, 1988c).

This Study of two firms in Sheffield city centre has been carried out under a contract with LTR2 Division of the Department of Transport, dated 28th March 1980. The Department of Transport has been interested for some time in various aspects of car-sharing, and the impact on car sharing of different work hour arrangements, and had previously carried out surveys of car-sharers in Government offices at Longbenton, Newcastle upon Tyne (TAU 1977) and Llanishen, Cardiff (TAU 1979) where flexible working hours were in operation. This study was designed as a continuation of those studies, in a city centre area where car parking was severely restricted. The prime objective was to measure levels of car sharing in locations with higher levels of public transport provision but more restricted parking, for later comparison with the results from Longbeutzen and Llanishen. The need for the study was occasioned by the desire to know more about the factors which influence people to share cars, and the characteristics of existing spontaneously formed car-sharing arrangements and participants. To obtain this information, details of the travel and work habits of the workforce concerned had to be collected and analysed. It was considered useful to try to establish any characteristics common to ad-hoc car-sharing participants as a basis for suggesting possible causal factors. The form of the study, in terms of the type of data collected, and its subsequent tabulation, was largely shaped by the need to provide data comparable to that collected in the aforementioned studies at Longbenton and Llanishen. Other work in the Institute on the prediction of demand for car- \ud sharing (Bonsall, 1980) and the establishment of experimental carsharing schemes (Bonsall et al, 1980) provided a useful basis for comparing the survey requirements for identifying potential car-sharers with those for identifying existing ones.

Twelve firms from the Holbeck Hunslet Industrial Area of inner Leeds were surveyed early in 1980 to determine the type, extent and severity of their transport problems. In order to compare and contrast these problems with those of firms located in an outer urban area twelve firms in the Stanningley area of Leeds were also surveyed. \ud \ud The samples have been treated as a series of case studies and the results for individual firms are available from the authors. This paper presents the survey results aggregated for each of the study areas. \ud \ud The predominant inner area problems revealed during the surveys, and amenable to solution by local authorities or the firms themselves, included: congestion and delays on the journey to work, on business trips and on commercial vehicle trips; inadequate parking at the firm; public transport difficulties for the journey to work; personal trips during the day; manoeuvring difficulties into and within premises for commercial vehicles; and delays during loading and unloading. \ud \ud Taken together, the results of the five surveys which were conducted at each firm suggested that in terms of the number of firms affected, and the degree of severity, transport problems did not seriously disrupt firmsr operations. Nevertheless they resulted in considerable lost time and in many cases a direct cost. There was a general inability of management to place a money cost against the problems which they mentioned and consequently there is the possibility that the impact of problems may be understated by local authorities. \ud \ud With the exception of parking at the firm, and to some extent manoeuvring difficulties, firms in Stanningley suffered similar problems to those in Holbeck Hunslet. In the case of Leeds it could not be concluded that inner area firms experienced different types of problems, and to a greater degree of severity, than firms located elsewhere in the urban area. Solutions applicable to the inner area are therefore, likely to be appropriate elsewhere. \ud \ud This paper is the first in a series reporting the results of surveys of samples of firms in Leeds and London.

The report evaluates the extent to which representative samples of manu- facturing and service firms drawn from the inner and outer London areas of South Shoreditch and Brimsdown respectively would be affected by proposed bans on 16 ton and 24 ton GVW commercial vehicles within Greater London.\ud \ud The proportion of commercial vehicle trips to and from South Shoreditch firms affected by the bans would be low and one-quarter of the firms would be affected by a 16 ton GW ban. One in five trips to and from Brimsdown firms is currently made by a vehicle in excess of 16 ton GVW, and two-thirds of the sample of firms would be affected. The majority of affected movements are by suppliers' vehicles rather than firms' own fleets. \ud \ud Three firms particularly likely to be affected were examined in more detail, and the implications of their changing to lighter vehicles investigated. A weight-specific 16 ton GVW ban would impose annual operating cost increases on all firms if they were to maintain existing levels of service with their own vehicle fleets. Under a 24 ton GVW ban two firms would incur cost increases while, for the operations considered, there would be a saving in annual operating costs for the third. The assumption that regulations governing vehicle dimensions and carrying capacity remain unaltered is crucial to the conclusions. \ud \ud Night time 16 ton and 24 ton GVW bans would affect a minority of firms, although the duration of the ban would be important. Weekend bans would not significantly affect the firms.

This paper presents the results-of a study of peak period travel times and potential causal factors conducted over a one year period on five radial routes. It describes the hypotheses tested and the survey design adopted and then presents results for inter-vehicle variation in travel time within 250 15 minute periods and for inter-period variation based on 1018 moving observer runs. Moving observer results are found to depend on flow over the previous half hour, and a modified time series analysis used to demonstrate this is outlinzd. The contriuhtion of other explanatory variables is also presented.

Previous studies of inner city manufacturing and service firms and studies of industrial relocation are examined to determine the problems of operating in inner areas, the factors causing firms to relocate, and the criteria which determine the choice of new site. These are related to the issues of retaining existing inner area firms and attracting new ones. \ud \ud Much of the previous work is limited in scope, largely qualitative, and frequently at a level of aggregation which makes identification of particular problems or factors difficult. Existing inner city firms perceive the transport problems of their own operations and of their employees as a major disadvantage of their present location, but there is a lack of quantified information on the extent and relative importance of these problems, and whether they are more severe for inner city firms. Transport issues in themselves are not one of the prime reasons causing firms to relocate, although the influence on availability of suitable labour is more significant. At a regional level transport is not one of the most important criteria in the choice of location, but as a determinant of site at the local level it is mentioned frequently enough to warrant further study. A number of other factors involved in these decisions are to a greater or lesser extent related to transport. \ud \ud To place firms' transport operations in a wider context transport costs, industrial traffic generation, and the effect of some forms of control are discussed.

1.1.1 Any new road, road improvement or traffic management\ud scheme could affect pedestrian journeys in its locality or\ud elsewhere. Some journeys may be affected directly, with\ud severance caused where the new road or road improvement cuts\ud across a pedestrian route, others may be affected indirectly with\ud a new road causing changes in traffic levels elsewhere. To\ud enable effects on pedestrians to be given proper weight when\ud decisions are taken, techniques are required that forecast the\ud effects of the scheme on the number and quality of pedestrian\ud journeys. This is particularly true in urban areas, since\ud effects on pedestrians may be one of the main benefits or\ud disbenefits of measures to relieve urban traffic.\ud \ud (Continues..)

This Report compares the results of the Before and After studies of some effects of the introduction of wheel clamps in Central London. Park and Visit and Vehicle Following studies were carried out in both cases, with Registration Number and Business Interview surveys taking place in the Before study only. \ud \ud The two areas of Central London which were studied comprised an area of Mayfair in which wheel clamps were to be introduced, and an area of Bloomsbury in which they were not. The surveys were designed to identify changes related to congestion and ease of access effects and so complement a series of surveys conducted by consultants for TRRL. \ud \ud The report describes each survey methodology, and presents the results of the Park and Visit and Vehicle Following surveys. A significant reduction in journey times is identified in Bloomsbury but not in Mayfair. However, the confidence intervals for Mayfair were too wide to determine whether the change in travel times in Bloomsbury was significantly different from the change in Mayfair. Significant reductions in search time are recorded in both areas, and a significant reduction in search plus walk time in Bloomsbury. An increase in empty meter spaces is identified in Mayfair and these findings from the Park and Visit surveys are supported by evidence from the Vehicle Following survey which suggests a drop in the degree of searching for meter spaces in Mayfair. \ud \ud Note: Further details of the survey are to be found in the associated technical note to this report (May et al, 1984b) and the individual reports on the Park and Visit and Vehicle Following surveys (May et al, 1984a).

Nineteen firms from the South Shoreditch area of LB Hackney were surveyed in Spring 1980 to determine the type, extent and severity of their transport problems. In order to compare and contrast these problems with those of firms located in an outer urban area, twenty firms in the Brimsdown area of LB Enfield were also surveyed. This paper presents the aggregated survey results for each study area. \ud \ud The most important inner area problems included : congestion and delays on the journey to work, on business and visitor trips, and on commercial vehicle trips; inadequate on-site and on-street parking at the firm and at the destination of business trips; public transport difficulties for the journey to work; on-site difficulties for commercial vehicles; delays during loading; and on-street loading. \ud \ud The most commonly reported effect of problems was lost time, however there were also instances of reduced efficiency, lost business, vehicle scheduling difficulties and staffing implications such as turnover and recruitment, staff dissatisfaction, the necessity to provide assistance for the journey to work or personal trips, ,and adjustments to working hours. There was a general inability of management to place a money cost against the problems which they mentioned although when estimates were made the costs were often considerable, and consequently there is the possibility that the impact of problems may be understated by local authorities. \ud \ud Firms in Brimsdown suffered similar types of problem to firms in South Shoreditch, and in most cases to a similar degree of severity. Solutions applicable to the inner area are therefore likely to be appropriate elsewhere.\ud \ud This paper is the second in a series reporting the results of surveys of samples of firms in Leeds and London.