Well water is very likely to be hard water because of its reliance on groundwater supplies. Hard water is predominantly found in groundwater, which is used by both wells and municipalities alike. Surface water supplies like large lakes or reservoirs are fed primarily by precipitation and rain, so they avoid contact with heavy mineral content. Groundwater seeps through layers of mineral-rich rock on its path to underground aquifers, absorbing hardness-causing minerals like calcium and magnesium along the way. Well owners rely on groundwater for their home water supply, so though well water it isn’t inherently hard, its prolonged exposure to the earth means it probably has elevated hardness levels. However, many city suppliers use hard groundwater for municipal distribution as well, so the problem is far from limited to well owners or rural areas.