The average water hardness in Minnesota is roughly 15-25 GPG (grains per gallon) however in some parts, it can be as high as 34GPG! Compare this to the United States average of 5-9 GPG and you can clearly see Minnesota’s level of hardness is particularly high. Why is this? The earth beneath Minnesota and Wisconsin is heavily made up of limestone (calcium), which is where hardness comes from. The city of Excelsior specifically provides drinking water to its residents from three wells that range from 448-465 feet deep. These wells draw water from the Prairie Du Chien-Jordan aquifer. And, though