§ the lack of specialist experience of some city traffic authorities in ATC which may lead to inadequate or poorly defined functional specifications and bid documents and thus disputes and delays in implementation (some systems have been out to bid 2 or 3 times);
§ the difficulty of reconciling the level at which designs and specifications are prepared to ensure that the system will operate as intended, satisfactory potential suppliers are not ruled out but unsatisfactory potential suppliers are ruled out;
§ the difficulty of combining an ATC system with other traffic management actions which are necessary to ensure that the system works efficiently and that traffic operations and safety are improved; there is no point in introducing state of the art ATC equipment but perpetuating poor junction design;
§ Institutional responsibilities - operations – in developing cities, traffic signals are often a traffic police responsibility. However, responsibility for planning, design, operation etc of ATC systems is more appropriate to traffic engineers. It is necessary to ensure that a satisfactory arrangement between traffic engineers and police is obtained (see Chapter 4 Institutional Arrangements)
§ Institutional responsibilities - maintenance – at this stage, there are few demand responsive ATC systems in developing cities on which to base maintenance experience but there have been cases where maintenance of fixed plan schemes has failed (e.g. Manila). A maintenance plan must be part of system design. In some cities, this can be handled readily by the traffic management agency (e.g. Leon, Sao Paulo, Curitiba etc) but in others it will be necessary to include an extended period for maintenance or staff training or a combination in the supply-installation contract.
Lessons – ATC is a key feature of Bank
traffic management projects/components. The incidence of traffic responsive
systems is likely to increase since real costs are reducing, reliability is
increasing and, although the operational benefits of demand response systems
may be marginal over simpler systems, (i) the benefits are real and (ii) they
raise the image and confidence of the traffic management agency. In the past,
there have been design, specification, procurement, responsibility and
maintenance issues and there are examples of schemes which have failed at the
design and bidding stages and have not been sustainable. Procurement has been a
special problem due to the desire of cities to (i) retain suppliers (of an
existing ATC system or of existing signals) or (ii) specify proprietary systems
or (iii) use of supplier credit for at least part of a system and these
arrangements make compliance with ICB guidelines difficult. Probably the only
solution within a Bank project is for the ATC system to be regard as a
counterpart loan contribution (provided the specified system is regarded as
technically satisfactory). Many cities do not have the necessary background or
expertise to deal with the issues and (i) there is a need for model documents
and procedures for the planning and procurement of ATC systems and (ii)
although consultants can be employed, training of local staff and budget
resources are vital to ensure sustainability. The institutional arrangements
for the system need to be clearly defined if the best is to be obtained; in
general, ATC systems should be the responsibility of the traffic management
agency and not the traffic police as the technology has moved beyond the areas
of competence of most traffic police.
Rationale and Objectives An efficient road freight transport system is essential to city and national economies and this is recognized in the primary objective of traffic management – to improve the efficiency of movement of “people and goods”. “Trucks” have a negative image arising from valid concerns over adverse environmental impacts (noise, emissions, visual intrusion), their contribution to traffic congestion (size and slowness) and the physical damage caused to roads (often due to overloading). The wider policy issues affecting trucks such as the potential to shift freight to other modes (rail), vehicle standards (size, safety, weight, driver qualifications etc), regulation of the industry (licences, axle load testing, entry to the market etc) and break bulk terminals (to break loads into smaller units which can be carried by trucks more suitable for urban use) must be part of a comprehensive truck policy but clearly outside the scope of “traffic management”. However, traffic management can play a part and the objective of urban traffic management with respect to trucks-commercial vehicles is
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