hown are the well sites which are used for repeated monitoring of ground water quality. There are more than 100 wells used for this purpose. Time series of more imortant parameters are displayed under Ground Water Quality of the Rio Minho Basin (accessed from Home page).

Although more chemical constituents and parameters are regularly analyzed (in monthly intervals), transferred to the GWIS of the Rio Minho Basin are the following: Ca,Mg,Na,Cl,SO4 (normally not available), pH value, electrical conductivity (EC) and total dissolved solids (TDS). For discussion of trends and eventual deterioration of ground water quality in certain parts of the basin, please go to Home page and select Ground Water Quality of the Rio Minho Basin. From that link, you may display time series for many wells and look at various diagrams and individual samples.