Defining Polycentricity in Different Levels

Hall and Pain (2006a, 3) demonstrate that a new urban spatial structure, polycentric mega-city regions, is emerging in the most highly urbanized parts of the world through a long process of very extended decentralization from big central cities to smaller ones. This is a new urban form consisting of 10 to 50 physically separate, but functionally networked town and cities clustered around one or more larger cities. The economy of these areas is dependent on information- intensive service industry, mainly advanced producer services.

Champion (2001, 664) demonstrates that there are three ways in which a polycentric metropolis or region can emerge. The first one is the “The Centrifugal Mode”. In a monocentric city, continuous growth may result in increasing land rents and accessibility problems to central city. As a result, production and service activities may move to alternative centers, which in time may rival the original CBD. Most of the former manufacturing belt cities are transformed in the contemporary era according to the centrifugal mode. The second way is “The Incorporation Mode”. A growing urban center might incorporate smaller centers in the surrounding area. These incorporated centers later may attract population and businesses and secondary centers may emerge around them resulting in a polycentric urban area. The third way is “The Fusion Mode” in which several independent centers might develop linkages and merge. In all these models, strong economic networking between settlements is the key point. Dallas-Ft. Worth and Miami- Ft. Lauderdale metropolitan areas are good examples to polycentric developments formed as a fusion between two independent centers.

Fishman (1990) demonstrates by the end of 1980s, the suburb and central city division started to become obsolete. Growth corridors stretching 50-100 miles brought the end of the monocentric city (Fishman 1990) . These corridors usually ended with an international airport and they included high-tech infrastructure (Batten 1995). Fishman (1990) calls these corridor cities as “New Cities”. Contemporary urban structure includes multiple corridor cities, in which cities are functionally interconnected. The best example is Randstad in the Netherlands. This new urban structure is multicentered. Batten (1995) calls the interlinked cities in one region as “network cities”.

In identifying the anatomy of the polycentric mega-city regions, Hall et al. (2006) argue that as suburbanization became an important trend, the traditional city boundaries will not be sufficient to understand the new metropolitan geography. People living miles away from a city commute daily to their works and this creates a economically interlinked regions. To overcome this boundary problem in defining metropolitan areas, American urban analysts have come up with Metropolitan Statistical Area (MSA) concept (Hall, et al. 2006), which has 50,000 or more population nucleus concentrated in a county with a central city. Around this central core, there are adjacent suburban communities having a high degree of social and economic integration with that core (U.S. Census Bureau 2000c). European geographers translated the (MSA) concept as functional urban regions (FUR) that has a core defined in terms of employment and density and a ring around the core defined in terms of daily commuting patterns to the core. Contiguous FURs make up mega-city regions (MCRs). MCR concept in Europe also derives from Combined Statistical Metropolitan Area (CMSA) concept in the US (Hall, et al. 2006), which is a grouping of contiguous metropolitan and micropolitan statistical areas according to a certain population criteria (1 million or more) (U.S. Census Bureau 2000a).

European geographers identified eight MCRs: South East England with London being the center, The Randstad in the Netherlands encompassing Amsterdam, The Hague, Rotterdam, and

Utrecht, Central Belgium with Brussels as the center, Rhine Ruhr region, The Rhine-Main Region in Germany with Frankfurt as the center, the EMR of Switzerland running between Zurich and Basel, the Paris Region, and Greater Dublin.

American geographers also responded to the MCR concept by identifying ten megapolitan areas. The megapolitan studies are started in Metropolitan Institute of Virginia Tech. Megapolitan area

is basically a large region with metropolitan and micropolitan areas that are interconnected physically through transportation networks and constitute a functionally interdependent urban network.

Other specifications in the definition are that megapolitan area combines at least two or more existing metropolitan areas; derives from contiguous metropolitan and micropolitan areas, will have 10,000,000 or more residents by 2040; and constitutes a distinctive cultural and historical identity. These megapolitans encompass only 20% of the US land area, but they have 67% of the total US population, meaning that they have the highest density areas. The basic unit of

megapolitans is counties. Megapolitan regions evolve as the spillover of the vastly expanding major metropolitan areas (Lang and Dhavale 2005; Lang and Nelson 2006). As the metropolitan area boundaries is pushed further out, the formation of mega-city regions become inevitable. Major metropolitan areas also have a polycentric structure in themselves in terms of

concentration of business activity. These megapolitans include nation’s largest and most important metropolitan areas and they define a larger territory than consolidated statistical metropolitan areas. The international airports are located in these regions. Thus, megapolitans are the gateways to the global economy (Lang and Dhavale 2005; Lang and Nelson 2006).

Carbonell and Yaro (2005, 3) demonstrate that between now and 2050, more than half of the US population growth and two thirds of its economic growth will occur in these megapolitan

regions. Megapolitans are expected to become the new CMSA definitions of the US Census Bureau by 2010. There are 10 megapolitan regions identified by Lang and Dhavale (2005) with their major metropolitan areas: Northeast with Boston, New York and Washington DC as their

major metro areas; Midwest with Chicago, Detroit and Pittsburgh; Gulf Coast with Houston and New Orleans; Piedmont with Atlanta and Charlotte; NorCal with San Francisco; Southland with Los Angeles and Las Vegas; Valley of the Sun with Phoenix; Cascadia with Seattle and

Portland; Peninsula with Miami and Tampa; and I-35 Corridor with Dallas and Kansas City.

The core economic competencies of megapolitans identified by Lang (2005) demonstrate that these megapolitan areas mainly specialize in service sector and high-tech employment. Northeast specializes in finance, Piedmont in banking, Southland in entertainment, and Peninsula

specializes in tourism. Cascadia, Gulf Coast, I-35 corridor, Nor Cal specialize in high-tech manufacturing, energy, and aerospace industry. Among the megapolitans Midwest is the only one that is dependent on manufacturing (Lang and Dhavale 2005). The major centers of these megapolitans are in cooperation with each other. More investment is being made in high-speed rail, broadband communications, and other infrastructure to establish stronger transport and economic linkages among the major centers of megapolitan regions. The government is developing tools such as the Transportation Infrastructure Innovation Act (TIFIA) to establish stronger connectivity between these regions (Carbonell and Yaro 2005).

From the definitions of MCRs and megapolitans vs FURs and metropolitan areas, we can derive that polycentricity can be defined at two levels: regional and intra- urban (metropolitan)

(Kloosterman and Musterd 2001). Regional polycentricity was first captured in Gottmann’s seminal work “Megalopolis” (Gottmann 1961) and today it continues with MCRs and megapolitans. Gottmann (1961) identified that in the Northeastern Atlantic seaboard of the United States a new urban structure is emerging. In 1960s, urban landscape between Boston and

Washington DC was comprised of continuous built up areas of manufacturing plants, residential communities, old urban centers, and new suburbs connected with traffic arteries (Gottmann 1961, 5). This tightly interwoven system transcended state boundaries and encompassed many different regions with 37 million people (Gottmann 1961, 7). Decentralization in US metropolis has continued after 1960s. Today American metropolis is characterized by a massive spurt of city building and the evolution of dispersed, polycentric spatial structure (Lang and Knox 2007, 5).

Graham (1997b, 23) argues that advanced telematics linkages tend to facilitate the development of polycentric urban regions through their support for extended complexity. He further suggests that with their polycentric constellations of centers, distributed across large areas, such urban regions are becoming the norm. Polycentric MCRs, CMSAs, and megapolitans define very large geographic areas and they are formed with coming together of FURs in Europe and metropolitan and micropolitan statistical areas in the US, which are also polycentric and include smaller cities and towns. We define intra-urban polycentricity at the MSA level in the context of this thesis. For example, Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area is a part of Baltimore-Washington Consolidated Metropolitan Statistical Area in census

definition. The CMSA is divided into three metropolitan divisions including Bethesda-

Gaithersburg-Frederick, MD Metropolitan Division, Washington-Arlington-Alexandria, DC-VA- MD-WV Metropolitan Division, and Baltimore-Towson, MD MSA. Each metropolitan area is divided into counties and cities are located under counties. Washington DC, Arlington.

Alexandria, Bethesda, Tyson’s Corner, Baltimore are all considered as cities in this CMSA. According to the definition of Metropolitan Institute of Virginia Tech Washington-Arlington-

Alexandria, DC-VA-MD-WV Metropolitan Statistical Area is a part of Northeast megapolitan region that includes Boston, New York, and Washington its major core cities. In this case, the megapolitan includes the CMSAs. As stated by the Metropolitan Institute, megapolitans are seen as the future definitions of CMSAs. As a conclusion, in this thesis, polycentric metropolis is defined as a metropolitan area including suburbs and commuting hinterland with wide-spread observations of employment sub-centers rivaling the CBD in size (Champion 2001, 663).