The continuing dispersion of international metropolitan areas is illustrated by recently released 2011 Census of India preliminary data for the Mumbai "larger" metropolitan area. The historical core, the "island" district of Mumbai (Inner Mumbai) lost population between 2001 and 2011, while all growth was in suburban areas outside the historic core. Indeed, since 1981, Inner Mumbai lost 140,000 residents, while suburban areas gained 13.2 million.
The larger metropolitan area is defined by district boundaries, the census division level below that of the state. The Mumbai Metropolitan Region Development Authority has a more "tight" definition, composed of smaller administrative units (municipalities), however that data is not yet available on the internet (Note). The larger metropolitan area includes four districts, two of which compose the city of Mumbai, Inner Mumbai (the historic core), and Outer Mumbai. The larger metropolitan area also includes the district of Thane, which is to the east and north of Mumbai and the district of Raigarh, which is to the south of Mumbai. The overwhelming majority of growth outside the city of Mumbai has been in Thane, which is accessible by land and bridge to Mumbai. Raigarh is less accessible from Mumbai and requires travel through Thane to reach.
The historic population trends of these four districts are described below. The evolution of the Mumbai urban form is illustrated by the following:
(1) The population growth rate peaked first in the core, Inner Mumbai, Outer Mumbai later and then fell substantially. Recent growth has been concentrated in the outlying districts of Thane and Raigarh. Figure 1 shows the population growth rate by district for each decade since the 1901 census.
(2) Much of the population growth was in Inner Mumbai until 1961. From 1961 through 1981, the bulk of the population growth moved to Outer Mumbai. By the 1981 to 1991 period, Thane emerged to virtually equal Outer Mumbai in its share of growth and has been dominant since 1991. Figure 2 indicates the share of the larger metropolitan area growth by district since 1901.
(3) The population of Inner Mumbai has risen comparatively little since 1961, with nearly all growth occurring first in Outer Mumbai and later in Thane. These two suburban areas now account for 90 percent of the larger metropolitan area population, double the 44 percent of 1961. Figure 3 illustrates the actual population, by district, of the larger metropolitan area from 1901 to 2011.
Inner Mumbai: The historic core (Inner Mumbai) registered 3.146 million residents, down from 3.327 million in 2001. The historic core now contains only 12 percent of the larger metropolitan area population, down from 40 percent in 1961, adding approximately 375,000 residents during that forty year stretch. Overall, since 1960, the island district has captured only 2 percent of the larger metropolitan area growth. This contrast with the period before 1951; Inner Mumbai had captured approximately 60 percent of the larger metropolitan region population growth between 1931 and 1941, and 49 percent between 1941 and 1951. However, Inner Mumbai's share dropped to a 26 percent share in 1951 to 1961 and an 11 percent share in 1961-1971. This is consistent with the overall trend in urban core population growth in metropolitan areas around the world, with population stalling or even declining once there is little greenfield land remaining for development. Inner Mumbai had lost population in the 1981-1991 census period, however recovered to reach its population peak in 2001. The 2011 population for Inner Mumbai was the lowest since the 1971 census. These population losses have occurred despite an unprecedented building boom of high-rise residential towers.
Outer Mumbai: The Mumbai Suburban district (Outer Mumbai) became a part of the city of Mumbai through a 1950 consolidation. As Inner Mumbai became fully developed, population growth shifted sharply to Outer Mumbai. By 2011, Outer Mumbai grew to 9.33 million residents, an increase of 7.95 million from its 1961 total of 1.38 million. Outer Mumbai captured 41 percent of the larger metropolitan area growth from 1961 to 2011. However, as the supply of greenfield land has been reduced, Outer Mumbai's growth has also slowed considerably. In each of the three decades from 1941 to 1971, Outer Mumbai grew by more than 100 percent. Outer Mumbai attracted only 19 percent of the larger metropolitan area growth, down from a 58 percent peak in the 1971-1981 period. The 2001-2011 increase of 744,000 (8.7 percent) was the lowest since the 1951-1961 census period, and was substantially below the 27.2 percent from rate from 1991 to 2001.
Thane: During the last 10 years, Thane has become the largest district in the Mumbai larger metropolitan area, with a population of 11.1 million, passing Outer Mumbai. Thane is now the largest district in India. In 2001 Thane had 8.1 million residents in 2001 and grew 35 percent to 2011. This, however, is down from a 55 percent growth rate between 1991 and 2001, reflecting a decline in the overall growth rate of the larger metropolitan area (see below). Thane has steadily increased its share of growth in the larger metropolitan area, from 24 percent between 1961 and 1971 to 55 percent between 1991 and 2001. Thane reached a peak in the 2001-2011 census period, capturing 74 percent of the larger metropolitan area growth. Since 1961, Thane has captured 49 percent of the growth in the larger metropolitan area and added 9.4 million residents. In each of the last two census periods, Thane has added 2.9 million residents, equal nearly to the population of the urban core, Inner Mumbai.
Raigarh: More remote from the core, Raigarh has experienced considerably slower growth than Thane, and until recently slower than Outer Mumbai. Raigarh grew 19 percent, from 2.21 million in 2001 to 2.64 million in 2011, an increase of 19 percent. This was the only census period since 1901 in which Raigarh grew more quickly than Outer Mumbai. Raigarh accounted for 11 percent of the larger metropolitan area growth between 2001 and 2011 and 8 percent since 1960. Raigarh added approximately 1.575 million residents from 1961 to 2001, more than four times that of larger Inner Mumbai (the urban core).
Overall Population Growth: Consistent with the general population growth rate declines witnessed in less affluent nations, the Mumbai larger metropolitan area is growing less quickly than in previous decades. Between 2001 and 2011, the area grew 17.3 percent, which is down from 30.9 percent between 1991 and 2001. The greatest growth had been between 1941 and 1951 (49 percent), with rates from 30 percent to 39 percent in each of the decades from 1951 to 1991 (Figure 4).
Mumbai: Penultimate Density, Yet Representative: The core urban area (area of continuous urban development) of Mumbai represents approximately 80 percent of the larger metropolitan area population. Mumbai is the third most dense major urban area in the world at nearly 65,000 residents per square mile (25,000 per square kilometer), trailing Dhaka (Bangladesh) and Hong Kong. Yet even at this near penultimate density, Mumbai exhibits the general trends of dispersion and declining density that are occurring in urban areas around the world, from the most affluent to the least. In the two Mumbai city districts, as in other megacities, housing has become so expensive that population growth is being severely limited. Overall, the Mumbai larger metropolitan area may also be experiencing slower growth as smaller metropolitan areas outperform larger ones, a trend identified in a recent report by the McKinsey Global Institute. Finally, the over-crowded, slum conditions that prevail for more than one-half of the city's residents could be instrumental in driving growth to more the distant suburbs of Thane and Raigarh.
Note: This "larger metropolitan area" definition is consistent with the cruder US Bureau of the Census delineation for metropolitan areas, which is based upon counties (in 44 states), rather than tighter definitions, such as municipalities or census tracts.
Photo: Chhatrapati Shivaji Terminus, formerly Victoria Terminus, Mumbai (by author)
Wendell Cox is a Visiting Professor, Conservatoire National des Arts et Metiers, Paris and the author of “War on the Dream: How Anti-Sprawl Policy Threatens the Quality of Life”