Recently I wrote to the Prof. Pink Pinguelli Luiz, of the Alberto Institute Luiz Coimbra de After-Graduation and Pesquisa de Engenharia (COPPE-RJ), on an article of it in the Periodical of Economists (Nr. 257, December 2010), on the challenges of Brazil in the energy area, of sanitation and others. As reference that it is in diverse subjects, and as physicist (as well as I am, for formation), I appreciated its article and its commentaries on the situation of the sanitation in Brazil. Of any angle, its commentaries are rational, and would be good if those that in fact plan and implement ours energy politics and of development, heard more to it and followed its suggestions. But I needed to make a clarification, on the basis of my performance of long date in the area of the basic sanitation and of treatment of sanitary sewers, on the commentary of the Prof. Pinguelli Luiz regarding fossas.

Commenting the goals of the government of President Dilma Rouseff for the expansion of the net of sanitary exhaustion, but not of treatment of sewer generated for this net, it answered that ' ' I find that the two things have that to be made, and if to make one of them is better of what not making none. I am not of the theory of ' ' how much worse melhor' ' , not. I find that if he could make the expansion of the net, that is better of what having black ditch in the houses of the poor people. He is better of what fossas.' ' (original emphasis). It occurs that, as many of that they act in the segment of basic sanitation know well, fossas represent a true and efficient system of treatment of sanitary sewers, with effectiveness of removal of organic load (DBO) comparable to the great stations of treatment of sewers (ETEs) generally existing.