Identifying Through Accessibility Planning How Sustainable Growth Can Be Achieved in the Compact City: a Case Study of Edinburgh
D Smith, Derek Halden Consultancy, UK
This paper reviews whether the goals of economic growth and improving accessibility in Edinburgh can be matched with sustainable development of the City.
This paper reviews whether the goals of economic growth and improving accessibility in Edinburgh can be matched with sustainable development of the City. Building from research at Edinburgh University, and analysis by DHC for the City Council congestion charging scheme, this paper considers options for transport system change and land use development to minimise travel needs whilst maximising opportunity.
The compact city model, describing a high density city with business, retail and cultural activity focussed in the centre and accessed by radial public transport corridors, accurately describes the spatial structure of many European cities. The compact city has been promoted as a sustainable urban form by many researchers, and the evidence from travel patterns in more decentralised cities supports this, though the debate over this issue continues. The city of Edinburgh in Scotland fits closely to the compact city model, as its high density historic centre provides the focus for the city?s business, shopping and culture, and is served by good quality bus corridors.
The monocentric compact city model encounters problems in the case of high economic growth, as the busy city centre often lacks space for development. Edinburgh?s economy has grown substantially in recent decades, mainly fuelled by growth in the financial sector. Increased wealth has led to greater car ownership and use, while much development has taken place at out-of-town business and retail parks. Furthermore housing development has not kept pace with employment growth and the number of commuters to the city, the majority of which travel by car, has increased. This paper uses accessibility modelling in conjunction with modal split data to illustrate how the location of these new developments offer both greatly reduced public transport choices and very high car accessibility in comparison to the city centre.
In light of congestion problems and the experience of out-of-town development over the last fifteen years, Edinburgh?s local government has put forward an ambitious plan for sustainable growth in the city for the next decade. This includes a new light rail network with the first line linked to a major mixed-use housing and employment development on the northern outskirts of the city (the Waterfront) and a further two lines on existing public transport corridors. Accessibility modelling is used to assess whether more sustainable travel patterns are likely at these new development areas. Plans also include improvements to the bus and heavy rail network and, far more controversially, a congestion charging scheme. After the success of London?s congestion charging scheme, the policy is seen as having the double benefit of reducing car use through demand management and providing a revenue source for public transport.
The proposed Edinburgh charging scheme has two charging cordons - one delimiting the city centre and the second just within the bypass marking the city limits. The two cordon scheme imposes a charge on radial vehicle movements and commuters originating outside the city boundaries, but suburban vehicle movements go unchecked. This covers the majority of vehicle movements but is a less than optimal solution, particularly in light of recent land use development in suburban areas. The construction and operational costs of an area based scheme across the city are however prohibitively high. Opposition to the policy has led to local politicians opting for a referendum on the transport plans.
Accessibility modelling shows that the radial nature of public transport links in the city severely restricts the number of people with viable public transport options to out-of-town development locations. If the new Waterfront development is to achieve sustainable travel patterns that are found in the city centre then the substantial improvement in public transport proposed must be delivered, in combination with the mixed high density land uses, public transport priority and parking restrictions already found in the city centre. Integrated land-use and transport planning is essential, and many recent planning and transport decisions have not been consistent with this vision. New accessibility planning processes have the potential to manage the joint working between land use and transport and to explain to businesses and residents the Council strategy.
Association for European Transport