There is a strong linear relation between instantaneous measurements of specific conductance and dissolved-solids concentration in the study area. In addition, real-time specific-conductance data are measured directly from field instruments at 15-minute intervals and uploaded to the database every 4 hours. The average value throughout a single day is expressed as the daily mean value. As such, the daily mean specific-conductance value can be used to estimate a daily mean dissolved-solids concentration using the regression equations in Table 2 of the USGS SIR 2004-5024.
Graphical representations of the relations are shown here. (Click image for larger version.)