Measuring racial residential segregation at different geographic scales in Cape Town and Johannesburg

Abstract

Since the formal dismantling of apartheid in the early 1990s, the South African government has placed much emphasis on redressing the social imbalances caused by apartheid, including overcoming patterns of segregation inherent in the apartheid city. The National Development Plan, in specifying its principles for the spatial development of South African settlements, outlines the principle of spatial justice: that apartheid's policy of confining particular groups to limited spaces must be reversed. In order to inform the future success of the National Development Plan's goal of social cohesion, research into residential segregation can provide one indication of how socially integrated South African society is. The purpose of this article is to measure racial residential segregation at different geographic scales for the South African cities of Cape Town and Johannesburg, and to measure how residential segregation has changed over time using data from the population censuses of 1991, 1996, 2001 and 2011. Theil's entropy index of segregation, applied to grid squares of varying spatial sizes, is used to calculate both racial diversity and racial segregation for both cities. The results show that from 1991 to 2011, segregation levels decreased at all geographic scales in both cities. However, despite this decrease, both cities remain highly segregated. If the census enumeration area or small area is used as the base from which to calculate segregation, Cape Town as a whole is more racially segregated than Johannesburg. However, Johannesburg is more racially segregated than Cape Town at larger geographic scales.