Here is my Ward Labs report from Verona which I would imagine is fairly similar to Madison water.
Verona, WI
pH 7.7
Sodium, Na 13 ppm
Potassium, K 1 ppm
Calcium, Ca 78 ppm
Magnesium, Mg 46 ppm
Total Hardness, CaCO3 387 ppm
Nitrate, NO3-N 4.8 (SAFE) ppm
Sulfate, SO4-S 6 ppm
Chloride, Cl 36 ppm
Carbonate, CO3 <1 ppm
Bicarbonate, HCO3 358 ppm
Total Alkalinity, CaCO3 293 ppm
Fluoride, F 1.31 ppm
Total Iron, Fe < 0.01 ppm