Characterization of residual soils for infiltration of reclaimed water

The effects of climate change and the increasing demand of water for domestic, industrial and agricultural uses will lead to the use of treated wastewater (reclaimed water). The aquifer recharge with reclaimed water can be an alternative for restoring volumes of water to aquifers, which may afterwards be used to satisfy those demands, especially in regions with water scarcity or where water presents poor quality. A two-year research conducted in the sewage treatment plant of Vila Fernando (Guarda, Portugal) has shown that the characteristics of reclaimed water are adequate to be infiltrated into the soil for aquifer recharge. As the study area for infiltration was very large and it was necessary to consider several technical, environmental and economic constraints, a multi-criteria analysis based on Geographic Information Systems was used in order to find the most suitable site for reclaimed water infiltration. Soil sample was collected at Quinta Goncalo Martins (Guarda, Portugal) for analysis, and the results have indicated that the site has favorable characteristics for reclaimed water infiltration.