What causes water hardness?

Water hardness primarily results from the presence of dissolved minerals, specifically calcium and magnesium. When water interacts with rocks and soil, particularly limestone and gypsum, it leaches these minerals, leading to increased concentrations of calcium and magnesium bicarbonates, sulfates, and chlorides in the water.

These minerals contribute to the overall hardness of water, which can affect not only the taste but also the effectiveness of soaps and detergents. When water is hard, it can form scale and deposits in pipes and appliances, making maintenance more challenging and impacting the efficiency of water heating appliances.

In contrast, iron can contribute to water quality issues but does not specifically define water hardness. The source of water, such as ponds or creeks, does not inherently determine hardness since it can vary significantly depending on the geology of the area. Moreover, while poorly constructed well-water supplies can lead to various contaminants, they do not directly cause hardness; rather, hardness is associated with the specific minerals present in the water. Thus, the correct understanding of water hardness is firmly linked to the dissolved calcium and magnesium found in the water.