Highways Agency - Safe roads, Reliable journeys, Informed travellers

4. Scope of Assessment

The M1 HOV Pilot scheme will be assessed by two consultants. The Monitoring Consultant will assess the impacts of the HOV scheme; the Scheme Consultant will assess the impacts of the widening and also the general operation of the HOV scheme, including publicity. The following sections describe the scope of the assessment in more detail.

4.1 Monitoring Consultant

The assessment of the impacts of the HOV scheme by the Monitoring Consultant will cover the following factors:

• The effect of the scheme on traffic. The consultant should consider the role of all the following: speeds, flows, journey times, queue lengths, headways, lane utilisation, vehicle classification, vehicle occupancy and travel patterns. Where appropriate, the effects should be determined on a lane-by-lane basis. The effects will be determined over a range of different conditions (e.g. special events, incidents or bad weather). The effect will be assessed both on the motorway itself and on the surrounding network (adjoining motorways and all-purpose trunk roads).
• The effect of the scheme on safety. This includes numbers and severity of accidents, and also accident risk. The effect will be assessed both on the motorway itself and on the surrounding network.
• The effect of levels of enforcement on compliance with the scheme (in particular, the numbers of rogue vehicles using the HOV lane).
• The effect of any changes to the operation of the scheme once it is installed (e.g. to the times of operation, the signing or the physical design).
• Feedback from drivers and/or local residents. This will include obtaining information before the HOV lane is installed, such as origin/destination data. This will enable comparisons to be made once the scheme is operational.

These factors will be defined in more detail in the document specifying the Monitoring Requirements for the project.

The assessment by the Monitoring Consultant should also attempt to identify any unforeseen side effects of the scheme. As much data as reasonably possible should be collected prior to the introduction of the scheme, to make it more likely that side effects would be identified. This will also mean that the assessment is flexible enough to allow for changes to the design of the scheme. The extent of the "before" data set will depend on how cost effective it is to collect the data.

The Monitoring Consultant will provide reports describing the results of the above assessment. These reports will be used by the HA for publicity and to answer questions on the operation of the scheme.

All of the data collected to assess the M1 HOV pilot scheme will form part of a notional data set of national traffic data, to be made available to the HA or consultants for other HA schemes.

4.2 Scheme Consultant

The following aspects fall outside the scope of the assessment by the Monitoring Consultant, and are expected to be carried out by the Scheme Consultant for the widening and HOV schemes:

• To establish the cost/benefits of the scheme against those predicted in the original business case. The results of the assessment by the Monitoring Consultant will be an essential input into this work. The Monitoring Consultant will provide information on the effects of the scheme; the Scheme Consultant will apply a monetary value to these and (if required) carry out a business case for further roll-out of HOV lanes.
• To optimise, as far as possible, the operation of the scheme. This includes the times of operation, the signing, the physical design, and also the levels and methods of enforcement. The Monitoring Consultant will assess the effects of any changes to the operation of the scheme once it is installed, but will not determine the policy.
• To assess the effects of widening the M1. A key requirement will be modeling the effects of widening the M1. The widening and the HOV scheme are being implemented simultaneously, and the Monitoring Consultant will be measuring the effects of these changes. The Scheme Consultant will have to estimate the expected effects of widening so that the effects can be disaggregated; modelling is likely to be the most appropriate method of estimating these effects.
• To determine the publicity strategy for the scheme (in particular, the publicity prior to the scheme opening).
• To assess the effectiveness of the publicity for the scheme and to monitor the press and public response to the scheme.
• To assess the maintenance required during operation of the scheme. This includes maintenance of the signs, the road surface and the Variable Speed Limit gantries.
• To mitigate any environmental effects of the scheme (e.g. any landscaping effects).
• If required, to determine the effects of construction (e.g. additional delays and construction noise).

The Highways Agency will determine the criteria under which the HOV scheme will be deemed a success, and also the criteria under which the scheme might be removed.

4.3 Discussion

In several of the assessment areas, there is no clearcut dividing line between the work of the Monitoring Consultant and the Scheme Consultant. Examples of these are in optimising the operation of the scheme and in dealing with publicity. For the operation of the scheme, the Monitoring Consultant will provide information on how the scheme is operating and analyse the effects of any changes to the operation, but will not be responsible for policy decisions on the operation. However, the Monitoring Consultant can make recommendations on the operation of the scheme.

Similarly, the Monitoring Consultant will provide reports on the scheme, to be used for publicity, but will not be responsible for the publicity itself. Monitoring the press and public response to the scheme could be carried out by either the Monitoring Consultant or the Scheme Consultant. As the Scheme Consultant is responsible for the publicity strategy, it makes sense for them to monitor the press and public response to the scheme.

There will be between a close liaison between the Monitoring Consultant and the Scheme Consultant, including a considerable exchange of information. For example, the data collected by the Monitoring Consultant will be a key input to the assessment of the widening scheme, and the results of the assessment of the widening scheme will be fed back to the Monitoring Consultant to enable them to disaggregate the effects of the widening from the effects of the HOV scheme.