While there are many purpose-built interchange facilities in London, interchanges frequently take place at locations where few formal facilities exist. For example, a suburban railway station with bus stops, a car park or a taxi rank close by is an interchange zone.
Interchange zones often comprise spaces that fall within the control of a number of different organisations and where the public transport operators may have little direct control over management of the space (for example, at clusters of on-street bus or coach stops). In many cases, the public highway, managed by Transport for London or the borough, is the 'glue' joining the public transport modes together. Transport providers should work with boroughs to define the scope of the interchange zone.
An interchange zone is often a gateway to the public transport network, in that it represents the interface between the public transport services and the surrounding area (or the 'urban context'). This includes connections by the most common mode of access, walking, but can also include provision for access by bicycle, cycle hire, bike sharing, taxi, bus or even the private car.
At the core of the interchange zone, the function of much of the public space may be strongly influenced by its role as a connection between public transport and feeder modes. At the periphery, an interchange zone may simply be the catchment from which passengers are drawn.
To help planners and designers identify the impact that interchange functions place on different public spaces within an interchange zone, spatial management guidelines have been set out. These guidelines will help optimise the quality of the interchange zone and passenger functions resulting in improved efficiency. In so doing, consideration should be given to the differing needs of those using the space and the activities going on there (both relating to interchanging or otherwise).
To reflect the complexity of interchange zones, these guidelines refer to different spaces within the interchange zone as one of three types:
When designing, or seeking to improve an interchange facility or zone, the spatial management principles should be applied at brief development stage, then considered throughout the design development to evaluate design concepts against anticipated needs. This should be subsequently written into the interchange facility management agreement to ensure design integrity is retained post implementation.
The attributes of these spaces are defined as follows:
Areas where passenger decisions take priority. Examples include decision points such as entrances, ticket offices or corridor junctions. At these locations there should be good sight lines, clear signage or transport information. There should be no non-essential physical infrastructure or visual distractions such as advertising, retail or other land uses that would serve to distract or confuse passengers.
Movement spaces connect decision spaces. Typically these include corridors and paths specially reserved for passenger movement and connections to/from/between transport modes or the surrounding area. These spaces should provide clear, unobstructed routes, matched to desire lines. Street furniture, plantings, advertising, information displays, retail boards or any other fixed items should not protrude into these zones but may be located adjacent to them.
Opportunity spaces include those areas of the interchange zone outside the core corridors of movement or decisions. They can accommodate cafés, retail entrances, retail display, seating or landscaping. Street furniture, advertising or other fixed or temporary infrastructure located in these zones must be managed so as not to protrude or interfere with the requirements of decision or movement spaces in adjacent areas.
Opportunity spaces may be located next to movement spaces such as the example in London's St Pancras Station where the movement space is 'The Street', connecting the Tube with National Rail. The retail facilities in the opportunity spaces are managed behind the column line so as not to conflict with movement in the movement space.