Most of our water is only moderately hard. It is much lower now that advanced treatment of surface water is our primary water source. Our wells have hard water because of the soil in our area. But our surface water has the same medium hardness as most California rivers and lakes. By mixing the well water and surface water, we lower the overall hardness to reasonable levels. In general, the expenses of operating residential water softeners are not needed.
Water hardness is from dissolved minerals from the soil like calcium and magnesium. There are no distinctly defined levels of what is hard or soft water. Typically, water is considered hard if the amount of dissolved calcium carbonate (CaCO3) is above 130 ppm or 8 grains per gallon. That can cause scale to build up in pipes, on faucets, and leave white spots on glass. The District’s water hardness is usually around 100 to 200 ppm (6 to 11 grains per gallon) depending on where you live. This hardness might leave white spots, but it will not damage appliances or water heaters.