Sistemas de aproveitamento de águas pluviais em comunidades de assentamentos informais

Abstract

Subnormal conglomerates are increasingly common in large urban centers, especially in the city of Rio de Janeiro. In these areas, urban infrastructure services are precarious, including restricted access to water supply and basic sanitation. This work aims to develop a design concept of an integrated and individual harvesting rainwater system that can be used in low income communities. Initially, was selected for the development of the project design, being chosen the Acomodado community, in the Paula Ramos Complex, Rio Comprido neighborhood, Rio de Janeiro-RJ. It is a densely occupied region with characteristics appropriate to the project. The methodology of the work consisted of 6 stages, such as: (1) characterization of the study area, (2) presentation / acceptance for the community about the project, (3) estimation of residential water demand, (4) determination of the potential of rainwater harvesting, (5) assessment of quantitative and qualitative aspects of rainwater and (6) development of rainwater harvesting project and cost estimate. The following were analyzed: topographic maps, IBGE and SNIS data, rainfall data from stations of the Rio Alert System (2018), characterization of water consumption with questionnaire application to residents, water quality analysis, and assembly of a prototype of treatment of their respective costs. Community characterization results include low population education, and infrastructure problems, especially in water supply. Thus, community acceptance for a new water supply alternative was high (94% of respondents). Such as for non-potable water demand, laundry, wash floor and toited consumption of 5.68 m³ / residence.mês or 52.14 L.hab-1.dia- 1. The quality of the rainwater presents compatible parameters for the use in non-drinking demands, according the recommended treatment. The amount of rainwater available in the region presents an average annual rainfall of 1477 mm.year-1 and 29 consecutive dry days from a historical series of 20 years. The development of the project in the community includes PET gutters, first flush and a low cost chlorinator. The integrated solution proposes in the Acomodado Community the division of the area into 7 supply zones connected to 6 reservoirs, so that the upstream group generates effective precipitation to supply the reservoir downstream, and so on up to the last downstream group situated at the entrance of the community. The reservoirs were calculated by the dry consecutive days method (GROUP RAINDROPS, 2002). As for the individual solution, each house would be responsible for its use of rainwater, and the reservoirs were calculated by the joint resolution method (SMG / SMO / SMU, 2005). The average costs of implementing the integrated and individual systems per household in the community was R$ 5,910.80 and R$ 2 986.48, respectively. It can be concluded that communities of informal settlements have the possibility of including new alternative forms of water supply. Due to the water crisis experienced, there is a need to think about access to water for all citizens, even in regions of high socio-environmental vulnerability.