Alternatives to the private car to access Bath City centre from the east are essential for a balanced transport strategy for the city. With the abandonment of a proposed Park and Ride site to the east of the city, Callidus set itself a project challenge to come up with an alternative solution.  The result is a new two tear interchange station at the roundabout junction between the A46 and the A4 London Road. The idea requires visitors to the City to make a seamless interchange from one bus to another bus at the interchange station.  Buses from dispersed locations outside of the city, including other rural Park and Ride sites, drop passengers off at the interchange.  The passengers then continue on their journey to the town centre on frequent shuttle services that operate along the A4 London Road to the centre of the City.

The interchange station is built within the existing A46 / A4 London Road roundabout junction.  It is proposed that a light weight structure is built over the central island of the roundabout. This would house the waiting areas, information boards and a help desk.  In addition, the interchange station could also include cafes, shops and tourist information. /span> From the roundabout level, lifts and escalators would transport passengers to the lower level where north-south orientated platforms would be located. General through traffic would remain but speeds would be reduced and safety barriers installed.  Sound insulating material could also be used to absorb noise from passing vehicles.

The circulation of buses around the roundabout could be on a special segregated bus lane and possibly in an anti-clockwise direction so that the bus doors always face towards the inner kerbline.  A tidal flow bus lane in the centre of the carriageway on the A4 as far as the Gloucester Road junction would give buses priority inbound and outbound from the city throughout the day.

This scheme utilises existing transport infrastructure to create a public transport interchange. The environmental impacts would therefore be minimal.  In fact it might be argued that this would be an enhancement to an existing heavily engineered highway scheme.

Potential Park and Ride sites could be located much further afield as the time taken for buses to get to the interchange is much less than if they also needed to travel into the centre of Bath.  Therefore, Park and Ride sites at the M4 / A46 junction or the A420 / A46 junctions could be economically feasible.

Reduction in motorised traffic from the east of the city will contribute to the wider Transport Strategy for the city. This in turn will enable environmental improvements to be made throughout the city.