Why do we need to measure conductivity?

Conductivity can give us a good indication of the amount of total dissolved solids (TDS) in a sample without having to analyze individual elements in the way that an expert or a chemist would. TDS consist of salts, minerals, and dissolved gases. These impurities or dissolved materials in the water increase the water's ability to conduct electricity. So, by measuring conductivity, we are able to get an idea of how impure a water sample is.