Brazil had 6,329 subnormal agglomerates in 2010 – irregular settlements known as favelas (slums), invasões (invaded properties), grotas (slums in deep valleys), baixadas (slums in low-lands), comunidades (poor communities), vilas (slums in villages), ressacas (slums in backwaters), mocambos (type of shack) and palafitas (stilt houses), among others – in 323 of the 5,565 municipalities. They concentrated 6.0% of the Brazilian population (11,425,644 inhabitants), distributed in 3,224,529 occupied private households (5.6% of the total).

Twenty metropolitan areas concentrated 88.6% of these subnormal households, and almost half of them (49.8%) were located in the Southeast Region. 

The subnormal agglomerates are often settled in areas less appropriate to urbanization, like steep hillsides in Rio de Janeiro, beach areas in Fortaleza, deep valleys in Maceió – locally known as grotas -, permanently flooded low-lands in Macapá, swamps in Cubatão, creeks and hillsides in Manaus.

67.3% of the subnormal households had either sewage collection networks or septic tanks; 72.5% received electrical energy with exclusive meter; 88.3% were supplied by water networks; and 95.4% had the garbage collected either directly or by garbage bins. 

More detailed information can be found in the publication Subnormal Agglomerates – First Results, which aims at showing how many people live and how many households exist in these areas, public services available and some social-economic features (population by sex and age; color or race; illiteracy and income). 

In order to better understand how IBGE defines subnormal agglomerates and how these areas were investigated in the 2010 Population Census, read the news "2010 Census improved the identification of the subnormal agglomerates":

www.ibge.gov.br/arquivos/noticias/
noticia_visualiza.php?id_noticia=2050

The full publication about subnormal agglomerates is available on page www.ibge.gov.br/home/estatistica/populacao/censo2010/aglomerados_subnormais/default_aglomerados_subnormais.shtm.

In addition to the tables containing information about the agglomerates, their limits are also available in shape (SHP) and KMZ (compatible with Google Earth) file formats.

Almost half (49.8%) of subnormal households are in the Southeast Region

The Southeast Region concentrated 49.8% of the 3.2 million occupied private households in subnormal agglomerates (23.2% in São Paulo and 19.1% in Rio de Janeiro).

The states of the Northeast had 28.7% of the total (9.4% in Bahia and 7.9% in Pernambuco). The North Region had 14.4% (10.1% in Pará). The figures were smaller in the South (5.3%) and Central-West (1.8%) regions:

6,329 subnormal agglomerates were identified in 323 municipalities (5.8% of the Brazilian municipalities).

48 municipalities were in the North Region (10.7% of the 449 municipalities of the region), mostly located in the inland of the states of Amazonas, Pará and Amapá. In most of the municipalities in this region, the subnormal agglomerates were settled in riparian areas, subject to recurring floods. In 52 (2.9%) of the 70 municipalities with subnormal agglomerates in the Northeast (3.9% of the 1,794 municipalities in the region), the agglomerates were located in the metropolitan areas. The Southeast concentrated almost half of the Brazilian municipalities with subnormal agglomerates (145 corresponding to 8.7% of the 1,668 municipalities in the region). Slightly more than half of them were in the metropolitan areas (75 municipalities or 4.5%) and the remaining in the inland of the states. While in a smaller scale, the South Region showed figures similar to the Southeast: 51 municipalities with subnormal agglomerates (4.3% of the 1,188 municipalities in the region), 38 in the metropolitan areas. The Central-West Region had only 9 municipalities with subnormal agglomerates (1.9% of the 466 municipalities in the region).

The subnormal agglomerates were often settled in areas less appropriate to urbanization, like steep hillsides in Rio de Janeiro, beach areas in Fortaleza, deep valleys in Maceió – locally known as grotas -, permanently flooded low-lands in Macapá, swamps in Cubatão, creeks and hillsides in Manaus.

In Rio de Janeiro, the older settlements were located in downtown and closer districts, where the job offers were concentrated.

In São Paulo, the settlements were in small areas far from downtown. A relevant feature in Belém is the large extension of the areas of subnormal agglomerates.

20 metropolitan areas concentrated 88.6% of subnormal households

The subnormal agglomerates prevail in the metropolitan areas:

20 of them housed 88.6% of the households in subnormal agglomerates in 2010, highlighted by the metropolitan areas of São Paulo, Rio de Janeiro and Belém, which, together, concentrated almost half (43.7%) of the households in subnormal agglomerates in Brazil. The largest proportions of occupied households in subnormal agglomerates in relation to the total occupied households in the metropolitan areas were in Belém (52.5%), Salvador (25.7%), São Luís (23.9%) and Recife (22.4%):

States in the North Region have the smallest percentages of households in subnormal agglomerates with adequate sewage collection and electrical energy

The 2010 Population Census raised information about the services of water supply, sewage collection, garbage collection and electrical energy supply. That information is essential for the differentiation and characterization of the subnormal agglomerates.

Degrees were created for each of these services considered as adequate:

In regard to the services of basic sanitation - water supply, sewage collection and garbage collection - and electrical energy supply, the percentages of adequacy of the households in subnormal agglomerates were always lower when compared with the regular urban areas in the same municipalities.

For some services, however, the percentages of adequacy of the subnormal households outpaced those of municipalities with no subnormal agglomerates.

Sewage collection was the service with the lowest degree of adequacy – sewage collection networks or septic tanks – for the households in subnormal agglomerates:

67.3% were adequate, 56.3% were connected to the sewage collection network and 11.0% were connected to septic tanks. It was also the service that showed the highest difference in the percentage of adequacy in relation to the regular urban areas (85.1%). The subnormal agglomerates in Tocantins (0.9%), Roraima (1.8%) and Amapá (7.7%) not even reached 8.0% of adequacy of the households in terms of sewage collection. Minas Gerais (87.2%), Bahia (86.8%) and Rio de Janeiro (83.2%) showed percentages higher than 80%.

As to water supply, 88.3% of the private households in subnormal agglomerates were adequate – supplied by the water distribution network. The smallest percentages of adequacy were in the North Region, highlighted by Rondônia (30.0%) and Acre (48.7%), where water was usually supplied by artesian wells or headwaters (69.1% in Rondônia and 45.5% in Acre). The highest percentages were found in Paraíba (98.5%) and Minas Gerais (98.3%).

The adequacy of the service electrical energy – supplied with exclusive meters – reached 72.5% of the households in subnormal agglomerates, while 99.7% had electrical energy. The difference is composed of households with electrical energy provided by supply companies with no meters (14.8%), households provided by supply companies with meters of common use (8.9%) and households supplied by other sources (3.5%). These numbers show that, while quite generalized in the subnormal agglomerates, electrical energy supply faced quality, safety and regularization issues. Roraima (15.8%), the Federal District (45.3%) and Amapá (45.4%) showed percentages of adequacy of the subnormal households lower than 50.0%. Eight states in the Northeast Region showed percentages of adequacy of electrical energy supplied to the households higher than 75%, highlighted by Ceará (92.8%), Maranhão (91.3%) and Bahia (85.7%).

95.4% of the private households in subnormal agglomerates in Brazil had adequate garbage collection – directly collected or by garbage bins. 79.8% of them were directly collected and 20.2% indirectly collected by means of garbage bins. The lowest degrees of adequacy of garbage collection in subnormal agglomerates were found in Roraima (31.5%) and Tocantins (58.2%). The remaining states showed percentages of adequacy higher than 84.9% and even higher than 98% as in Paraná (99.0%), São Paulo (98.8%), Santa Catarina (98.8%) and Rio Grande do Sul (98.4%).