Application of statistical control on water quality in cisterns in the semiarid Pernambucano

In the Brazilian semi-arid region, it is necessary to use alternatives for the better use of water, since evapotranspiration rates exceed rainfall rates, which may favor salt accumulation in cistern systems. This work aimed to investigate the water quality of cisterns from communities in the semiarid region of Pernambuco state. Thus, the following physicochemical and microbiological characteristics of cistern water were monitored: color, turbidity, total dissolved solids (T.D.S.), salinity through electrical conductivity (EC), pH and total and fecal coliforms. For monitoring, statistical quality control techniques, control charts and process capacity indices were employed. Results were found with high values for microbiological, total and fecal coliforms in most samples. Control charts showed no abnormality in the process. The probable reasons for the contamination of cistern water is the lack of cleaning of the gutters that are part of the stored water catchment system. In the northeastern semi-arid population, people are looking for ways to use natural resources to ensure survival and water quality is seen as a guarantee for quality of life.