Improved Ecosystem Services and Environmental Gentrification after Rehabilitating Brazilian Urban Streams

Abstract

The high levels of environmental pollution observed in urban freshwater ecosystems result in losses of ecosystem goods and services, reducing the well-being of human populations in densely populated tropical cities. The Belo Horizonte Metropolitan Region (BHMR) resembles other megacities in the Global South, with inadequate collection and treatment of domestic sewage being an important source of environmental degradation. However, urban stream rehabilitation can improve ecosystem quality and the physical and mental well-being of local citizens. Therefore, the objective of this study was to assess whether the rehabilitation of three BHMR streams and the increased provision of ecosystem goods and services for local residents were associated with environmental gentrification and public health issues. To achieve this objective, we asked three questions. (i) Was there socioeconomic improvement in the households located near the rehabilitated streams? (ii) Did property values appreciate near the rehabilitated streams? (iii) Was the relative incidence of diseases decreased in the residents living near the rehabilitated streams? We tested three hypotheses. (H1) The socioeconomic profile of the households in the areas neighboring the rehabilitated streams improved. (H2) The property values of residences in the areas neighboring the rehabilitated streams increased. (H3) The incidence of waterborne and other types of diseases in the areas neighboring the rehabilitated streams decreased. To answer the first question and hypothesis, we compared 2000 to 2010 census tracts in the areas neighboring the rehabilitated streams with others in the municipality of Belo Horizonte (BH). We observed non-significant socioeconomic and demographic differences. To answer the second question and hypothesis, we used real estate transactions between 2009 and 2018 using hedonic models. After controlling for multiple interacting variables, we observed real estate appreciation after stream rehabilitation. To answer the third question and hypothesis, we analyzed the association between the prevalence of waterborne diseases, vector-borne diseases, and other diseases in the residents living near the rehabilitated streams. To do so, we analyzed hospitalization data from 2005 to 2016 for residents neighboring the streams versus BH. We observed a significant increase in the prevalence of waterborne and vector-transmitted diseases until two years after the stream rehabilitation, followed by a decrease until 2010. Trends for other types of diseases differed from these and mostly followed the general tendencies of BH, indicating different temporal variations. Our results highlight that ecosystem goods and services fostered by urban stream rehabilitation have potential contributions to the well-being of urban populations. The economic analyses applied in the paper have clear policy implications in support of urban stream rehabilitation. Although South American countries lack mandatory rehabilitation investments, Belo Horizonte’s example can inspire other interventions in tropical megacities.