Highways Agency

Conclusions

The Highways Agency's feasibility study on high occupancy vehicle (HOV) lanes concluded that introduction of an HOV lane would be feasible at each of the four locations being investigated.

The preferred option is to introduce the HOV lane as an 'open access' (non-segregated) peak period off-side running lane. It is recommended that HOV lanes should generally start about 0.5km before the off-slip nose of the initial junction. They would then be continuous until their end about 0.5km after the off-slip nose of the terminal junction.

This solution would separate the potential conflict points of slip roads and HOV lane transitions and thus avoid combining weaving movements for both reasons at coincident locations. However, detailed layouts should be considered further prior to implementation. This should include micro-simulation modelling of the preferred layouts.

For the M3 and M61, the preferred solution is to convert the third lane or off-side lane to an HOV lane in the required peak periods. Similarly, for the M1 and M62, the preferred solution is that during widening to four lanes, the fourth or off-side lane would be allocated as an HOV lane for use in the required peak periods. The incremental costs of introducing HOV lanes during widening compared to introduction of HOV lane schemes on an existing motorway are relatively low, as much of the temporary traffic management and roadside equipment enhancement costs would be already included in the widening schemes.

The preferred engineering solution for each location was assessed using an outline traffic and economic assessment. This assumed a 5% reduction in carriageway traffic as a result of transfer from single-occupancy vehicles to High Occupancy Vehicles. Further sensitivity testing was then carried out.

Ranking of each location has been based on the results of the preliminary economic analysis.

This showed that the schemes already scheduled to be widened to D4M standard (M62 and M1) are likely to outperform schemes that will remain as D3M (M61 and M3). Introduction of HOV lanes during widening would also comply with the current philosophy of 'locking-in' the benefits of the increased road capacity. The M62 is forecast to be the best scheme in cost benefit terms, followed by M1 and then M61. Consequently, in economic terms, the feasibility study recommends that the M62 (junctions 25-27) scheme is taken forward for further study.

An M1 HOV lane scheme is economically viable, either as a southbound AM peak lane only or through introducing an HOV lane in both directions, each operating in the dominant peak period in that direction.

• Download the detailed feasibility study (1.2MB PDF)