Adaptability of the Structure to the Conurbation of Glasgow

It is now possible to abstract the proposed macro- and micro-structure for the conurbation of Glasgow in order to demonstrate how closely it resembles the abstract model of the polycentric net. The highlighting of all districts and towns (by circles with the appropriate radii), of the primary and secondary nodes (by dots of the appropriate visual weight) and of the primary and secondary transport links on the figure-ground base map (Fig. 5.20) illustrates that the structure is generated for, and follows closely, the existing pattern of development of the conurbation of Glasgow; but it is visually confusing. Therefore the base map with all details of the existing figure-ground is eliminated so as to show the city structure as a diagram (Fig. 5.21). This diagrammatic representation of the city allows an immediate understanding of the polycentric nature of the conurbation and of the network of linkages between the nodes; it also demonstrates how closely the real structure of the conurbation resembles the abstract pattern of the polycentric net.

The system of the polycentric net is open-ended and can adapt to any change in socio-economic conditions and can cope with any growth or shrinkage of population. In a real city this process is complex. If the population grows the question is which green areas should be developed; the decision does not involve major restructuring of an existing area and does not directly affect the

existing population of districts or towns within the conurbation. Therefore expansion is relatively easy to manage. If, however, the population shrinks the question is whether, and if so which, built-up areas of the city could contract, and then existing communities will be directly affected.

One needs to remind oneself at this stage that the micro-structure will work efficiently only if all the centres are supported by the appropriate size of population, and this is currently not the case in all areas of the existing conurbation of Glasgow. Unfortunately data for the conurbation as a whole are not available; therefore this discussion concentrates on the city of Glasgow including Rutherglen (1975 boundaries). If 40% of the city area is allocated to open land (see section 3.3) and only 60% of the total area is built upon then the gross population density of Greater Glasgow is around 55.7 persons per hectare (pph) and therefore only a little short of

5–21. Diagram of the structure of the conurbation of Glasgow with the figure-ground eliminated

the 60 pph benchmark which is believed to be necessary to support local services and facilities and public transport. Glasgow’s population is accordingly on average only a little too small, but it is rather unevenly distributed over the city area (Fig. 4.32). Those districts with a population below the city average (with the 1975 boundary about 33.4 pph over the total area equivalent to a population of 55.7 pph over 60% of the area) represent 53.5% of the total city area but accommodate only 32% of the city’s population (Fig. 5.22). It is these

5–22. Areas in the city of Glasgow below the required average population density (based on Glasgow City Council, 1995)

districts that do not achieve a sufficient population to support local services and facilities. Many of them are located at the edge of the city and incorporate a considerable amount of open land over and above the 40% set as threshold value, but a number of them are located in the central development zone on either side of the River Clyde.

There is the additional problem of outmigration. The city population (excluding Rutherglen) fell from 1,055,000 in 1960 (Glasgow City Council, 1996, pp. 15–18) to 622, 333 (Glasgow City Council, 1995) with only insignificant changes to the city boundary and area. This amounts to a population loss of 41% in that period. The decline was dramatic during the 1960s and 1970s, but during the 1980s and 1990s there was a steady decline in the rate of outmigration (between 1980 and 1993 around 3,000 persons or 0.5% a year with a falling tendency). Not to cope with the situation of uneven distribution and continued loss of the population would mean that the micro- structure would not work optimally in over half of the developed areas of the city. There are three ways of dealing with the mismatch between population and built-up area.

• Strategy one: increase the population in those areas with a population density below the city average (around 55.7 pph over 60% of the total area of Greater Glasgow). This strategy is based on the assumption that people could be attracted to move from the countryside or from the conurbation but outside the city into underpopulateo areas of the city. With the proposed micro- structure the city population of Glasgow (including Rutherglen) would have to increase by 21.4% (145, 226 people).

• Strategy two: increase the population in those areas below the threshold average by redistribution of population from areas with densities above average. This would require that 21.4% of the total city population living in districts with average and higher than average density would have to move into the 53.5% of the city’s districts with densities below average.

• Strategy three: decrease the size of the built-up area of the city in those districts below the population average. This strategy is based on the

assumption that the population in the higher-density area will or should not be reduced and that the population in the lower-density areas needs to be

concentrated into a considerably smaller area to achieve the required gross density. This approach would involve demolition of existing fabric in and the dislocation of people out of 21.4% of the city area (4,348 ha).

Strategy One

The first strategy needs little further discussion as its advantages, but also its difficulties, are obvious. There is competition between urban districts and towns; some of those outside the city boundary of Glasgow offer better conditions for industry, services and other facilities to locate, and this causes outmigration. If competition could be changed into co-operation—clearly, the sustainability of individual places can be seen only in conjunction with the entire urban region— and if Glasgow could be made more attractive in terms of workplaces and general living conditions, then it might be possible to attract people into the city and achieve a more balanced population and workplace distribution in the conurbation and city region. This surely is the aim of many local agencies and departments but requires strategic plans for the regeneration of the entire region rather than individual areas in it.

Strategy Two

The second strategy considers that there may not be any need for an increase in the city’s population or a decrease in the city’s area if a more even distribution of population could be achieved in the individual built-up areas of the city. The problem with this strategy is that the weak areas of the city would be strengthened by weakening the strong areas, and this seems to be a problematic option. The densely populated neighbourhoods and districts are all historical areas of good spatial structure and form, and part of their quality is the high concentration of people which in turn supports good services and facilities. Quite apart from the fact that decanting population from the higher-density areas may reduce their quality and perhaps even viability, this strategy is likely to involve a considerable amount of restructuring of urban areas and dislocation of people and might therefore be economically and socially unacceptable.

Strategy Three

The third strategy has been widely, and often, discussed in Glasgow, causing considerable commotion at times. There have been suggestions that the city should get rid of the most deprived areas and relocate people from these areas into more advantaged districts. Others have suggested that areas at the very periphery of the city should be phased out and returned to farmland, regardless of their level of deprivation or otherwise, because they are furthest away from central services and facilities. It so happens that some of the most deprived areas are at the very edge of the city. Many of those who in recent decades have spent considerable sums of money and have made huge efforts to improve deprived areas—specifically the local housing associations and co-oper-

5–23. City of Glasgow: the most deprived areas (based on Glasgow City Council, 1995)

atives—have reacted strongly to such suggestions. They point out that there are communities and people in these areas who want to stay and further improve these districts. They also believe that demolition of housing stock and dislocation of people would only repeat the disasters of the comprehensive development of many urban areas immediately after the Second World War.

An examination of the location of the most deprived areas reveals that they are not only located at the very periphery of the city but also immediately north, east and south of the well-structured central belt (Fig. 5.23). Therefore the level of deprivation on its own cannot be the basis for a decision to eliminate an urban area—if such a decision were ever to be made—because demolition frequently means shifting part of the problem elsewhere; the location of areas has to be considered as well.

It would make sense to start consolidation of the city in the more central areas because this would achieve more continuity of development with the appropriate structure and density right next to, and in good connection with, the already densely developed and well-structured city centre and the northern inner south- east/north-west development belt west of it. This would result in the priority regeneration of areas directly east, south and north of the city centre, and indeed one such project is already under way with the regeneration of the Crown Street area in the Gorbals, presently Glasgow’s most coherent approach to the regeneration of a deprived area just south of the city centre, intended to bring people back into this inner-city zone. However, the regeneration of all urban areas in the city to the same levels of quality and density as pursued in the Crown Street Regeneration Project might not be feasible unless the regeneration would entice more people and businesses to locate in the city. This reinforces the conviction that one strategy alone cannot solve all problems, and a combination of them may have to be applied.

Combination of Strategies

In reality all three strategies may well form part of a regeneration programme for the city and conurbation. All areas other than those that are already rather dense and well structured may undergo some form of compaction; some people and businesses may be attracted into the city because of added bonuses resulting from ongoing regeneration programmes; and some areas may be so derelict and so badly located that their regeneration into sustainable entities may prove too costly and thus they may actually be given up in favour of the regeneration of other, more promising areas.

A decision as to the right strategy needs to be based (a) on a thorough understanding of the qualities and deficiencies of all areas on the basis of the sustainability criteria already used earlier, and (b) on an assessment of the amount of restructuring required in each neighbourhood and district and the long-term costs and benefits of their restructuring. Regeneration of a district is in the end viable only if it can achieve within reasonable economic and social costs the required population density as well as affordable services and facilities and public transport, because only then will a district become a well-functioning and attractive part of a sustainable conurbation or city region. This in turn means that a decision to regenerate an individual district will have to be based (a) on the long-term costs and benefits of regeneration based on each of the three strategies, and (b) on the impact of the regeneration of a district on the entire conurbation and urban region.

5.5 Conclusions

The investigation of the city region and conurbation of Glasgow has generated evidence of the viability of the micro-structure of a more sustainable city. The

investigation has also shown that for the region and conurbation of Glasgow the polycentric net is the most suitable macro-structure.

That Glasgow fits the polycentric net is, of course, no evidence of the general applicability of this macro-structure model of a city region. It happens to fit because of the specific development patterns as a result of specific topographical conditions of the city region, a unique historical development process and specific socio-economic conditions. Other city regions can be expected to have different features and may therefore demand the application of a different macro-structure model or even

5–24. The macro-structure of the Rhine-Main region in Germany (based on Fig. 3.29 which is reproduced by kind permission of the Magistrate of the city of Frankfurt am Main)

a combination of different models.

The admittedly rather superficial return to the Rhine-Main region in Germany

(Fig. 5.24) leads to the conclusion that in its centre (Frankfurt am Main)

conditions may be similar to those in the Glasgow conurbation, albeit with a more compact inner area, specifically along the river, and more fragmented outer areas. But then this central area of the region is linked to rather fragmented development clusters, some of which form chains along transport routes. The overall structure of the region is still a kind of polycentric net but with two dominant linear development strips: a major east-west one along the rivers Rhine and Main (with Mainz/wiesbaden to the west, Franlcfurt in the middle and Aschaffenburg to the east) and a major north-south one in the centre of the region (with Darmstadt to the south, Frankfurt am Main in the middle and

Wetzlar/Giesen to the north) (see Magistrat der Stadt Frankfurt am Main, 1997, p. 22; 1995, pp. 11,15). The configuration of the Rhine-Main region is therefore a combination of net and linear development.

It appears therefore that the macro-structure of an individual town or city is in the end of relatively little significance when it comes to the definition of the form of a more readily sustainable conurbation or city region. It is the entire polycentric net that has to be taken into consideration; the existing conditions of such a net cannot be ignored, let alone easily changed. However, of considerable significance with regard to sustainability is the micro-structure of all parts of the net, which consists of a hierarchy of provision centres of different capacity (from neighbourhood to district to town and city centre) linked by a hierarchy of transport links of different capacity (from walkway and cycle path to motorway and from bus to LRT and railway). This structure provides not only access throughout the city, conurbation or region to a variety of services and facilities and to open land but also a high degree of mobility and in spatial and formal terms the potential for imageability of individual neighbourhoods, districts and towns.

A precondition for the viability of the micro-structure is a relatively modest degree of compactness of the development clusters (e.g. an average gross population density of around 60 persons per hectare throughout the city region). Compactness is not, however, required, and not even possible, in the city or city region at large, because of the inclusion of open land. It is needed in the individual neighbourhoods and districts and perhaps also towns that form the city or region.

This confirms what was concluded at the end of the evaluation of city models in Chapter 3. A city, conurbation or city region can have any of a variety of macro-structures and still score well with regard to sustainability criteria. Preconditions are that it has in all its parts the appropriate micro-structure and that extreme forms of compactness and concentration of population (in the form of a very large core city with a rather remote countryside) and extreme forms of decentralisation and dispersal of population (in the form of a galaxy of settlements or neighbourhoods) are avoided.

It has become clear in this investigation that the search for a generally valid sustainable city form is a bit of a red herring. What really counts is the search for a sustainable conurbation or city region. It has been demonstrated that in the region and conurbation of Glasgow a rudimentary micro-structure of the required nature does already exist and that this structure can be improved and expanded across the entire region without major upheaval and without major restructuring of the existing development pattern. What still requires investigation is how the micro-structure can be implemented in individual urban districts; this will be demonstrated with the help of a number of examples in Chapter 6.

References

The Courier, Bearsden, Milngavie & Glasgow West, (1997) Issue 553, Friday,

21 November.

Gehl, J. (1987) Life between Buildings: Using Public Space, Van Nostrand Reinhold, New York.

Glasgow City Council (1995) Ward Profiles, City Planning Department, Glasgow.

Glasgow City Council (1996) Glasgow’s Housing Plan 1996: Draft for

Committee, Housing Department, Glasgow.

Magistrat der Stadt Frankfurt am Main, Dezernat Planung, Amt für kommunale Gesamtentwicklung (1995) Bericht zur Stadtentwicklung Frankfurt am Main

1995.

Magistrat der Stadt Frankfurt am Main, Dezernat Planung, Amt für kommunale Gesamtentwicklung (1997) Stadt-Pläne: Stadtentwicklungsplanung im

Vergleich,

Internationaler Frankfurter Städtebau-Diskurs, Deutsches Architektur-Museum 29. Februar-1. März 1996.

Moudon, A.V. (ed.) (1987) Public Streets for Public Use, Van Nostrand Reinhold, New York.

Richards, B. (1990) Transport in Cities, Architecture Design and Technology Press, London.

Zuckermann, W. (1991) End of the Road: The World Car Crisis and How We