We are not aware of any new research that indicates soft water will increase water intake or milk production. Softening water for a herd of dairy cows will be expensive as large quantities of salt will be required. Also, the extra sodium in soft water will increase the cation intake of cows and may increase milk fever problems if offered to close-up dry cows. When cows receive hard water, you can estimate water intake and calculate the grams of calcium or magnesium consumed via the water and add it to feed sources. If water is high in iron (bacterial growth) or sulfur (less intake), treatment may be beneficial. Hard water can reduce the effectiveness of your cleaning procedures and soaps.
Mike Hutjens, Extension Dairy Specialist, University of Illinois - Illini DairyNET
