Direito à moradia em cidades sustentáveis: parâmetros de políticas públicas habitacionais Natal 2013

The right to housing is included in several international human rights instruments and in Brazilian legal system integrates the constitutional catalog of fundamental social rights (art. 6) and urban development policy (art. 182 and 183). Besides, it is for all federative governments its effectiveness by building programs and improvement of housing conditions and sanitation (art. 23, IX), which justifies the investment in urban planning and public policy of housing affordability because they are tools for achieving this right. Newer strategies in this area have been based on tax incentives, combined with the mortgage as a way to induce the construction of new housing units or reform those in a precarious situation. However, there is still a deficit households and environmental soundness, compounded with the formation of informal settlements. Consequently, we need constant reflections on the issue, in order to identify parameters that actually guide their housing policies in order to meet the constitutional social functions of the city and ensure well-begins of its citizens (art. 182). On the other hand, the intervention of the government in this segment can not only see the availability of the home itself, but also the quality of your extension or surroundings, observing aspects related to environmental sanitation, urban mobility, leisure and services essential health, education and social assistance. It appears that the smoothness and efficiency of a housing policy condition to the concept of adequate housing, in other words, structurally safe, comfortable and environmentally legally legitimate, viable from the extensive coordination with other public policies. Only to compliance with this guideline, it is possible to realize the right to housing in sustainable cities

Decaimento bacteriano em lagoas de estabilização no Nordeste brasileiro

Stabilization pond system consisting in more sewage treatment used in Rio Grande do Norte (RN), Brazil, representing about 90% of all systems. Fecal bacteria are removed mainly facultative ponds and in maturation ponds. Many factors influence bacterial decay, such as the levels of pH and DO, temperature, light intensity, HDT and nutrient availability. The bacterial decay rate (Kb) is calculated considering many variables, but the hydraulic regime is a significant influence for microorganisms removal, and the dispersed flow which best characterizes a stabilization pond. However, some authors developed equations for the Kb accordant plug flow and complete mixing. This research study aimed to evaluate the bacterial decay of fecal coliform and Enterococcus sp. in stabilization ponds designed to treat domestic sewage, full-scale, in RN. All systems have assessed pretreatment, a facultative pond (LF) followed by two maturation (LM1 and LM2). The parameters availed were: temperature, pH, DO, BOD5, COD, fecal coliform, Enterococcus sp., Chlorophyll a, total suspended solids, fixed and volatile. In general, there were not significant differences for pH, DO and temperature in the ponds, except for the new systems, since they have low flow and hydraulic loads. The removal of organic matter in the ponds was low, about 70%, and nearly all are overloaded organic and operational problems. The bacterial removals were low, with average 96% for LF for fecal coliform, and 98% for Enterococcus sp.; LM1 were in itself a removal for fecal coliform about 71%, and 81% for Enterococcus sp.; LM2 have efficiency of 69% for fecal coliform, and 68% for Enterococcus sp. The equation proposed by Von Sperling (1999), according to the dispersed flow regime, generated empirical values of Kb more approximate to calculated values of Kb. On average, the calculated Kb to coliforms in the LF was 0.31 d-1, and for both maturation ponds were 0.35 d-1. For Enterococcus sp. the average was 0.40 d-1 for LF, 0.55 d-1 for LM1, and 0.58 d-1 for LM2. These results also showed that the Kb obtained in full-scale systems are smaller than those found in pilot-scale ponds. Moreover, one can say that the equation proposed by Marais (1974), according to the complete-mix regime, overestimates Kb. Actual results of Kb indicated that fecal coliforms are more resistant to adverse conditions present in stabilization ponds than Enterococcus sp., therefore, an indicator of microbiological safety and efficiency. The factors significant interventions in the rate of bacterial decay were concentrations of COD, the organic loading and HDT. The few Kb relationship between pH, DO and temperature were not significant. Finally, we conclude that it s essential to correct operation and maintenance, for not performing these activities is one of the main factors contributing to low rates of bacterial decay.