Multielemental detection using Instrumental Neutron Activation Analysis (INAA) and Proton-Induced X-Ray Emission (PIXE) of drinkable water of Florence (Italy) is described. The concentrations of 52 elements were measured. No chemical treatment was performed on the samples, before or after irradiation. On the basis of an appropriate combination of the two analytical techniques, a procedure for aluminum determination was developed. Results are briefly discussed from a methodological point of view.