Water chemistry data from: Mariner, R.H., Presser, T.S., Evans, W.C. and Pringle, M.K.W., 1990. Discharge rates of fluid and heat by thermal springs of the Cascade Range, Washington, Oregon, and northern California. Journal of Geophysical Research: Solid Earth, 95(B12), pp.19517-19531, https://doi.org/10.1029/JB095iB12p19517. Water chemistry data was digitized for 148 samples. Reported attributes include: Sample name, Type, Collection date, Reported latitude, Reported longitude, Region, State, Latitude, Longitude, Location resolution, Location error, Source, Discharge, Temperature, pH, Calcium (Ca), Chloride (Cl), Fluoride (F), Bicarbonate (HCO3), Potassium (K), Magnesium (Mg), Sodium (Na), Silica (SiO2), Sulfate (SO4), Cations, Anions, Salinity, Charge balance, Isotopic composition of oxygen in water (Delta 18O H2O), Isotopic composition of oxygen in sulfate (Delta 18O SO4), Author comment, Digitizer comment. Data was digitized from Tables 1 and 2. The following tables were not digitized: Table 3: convective heat discharge of thermal springs and thermal aquifers estimated from geothermometer data. Table 4: Quaternary volcanic rock extrusion rates and convective discharge rates of thermal waters.