The water distributed by EMATSA favourably exceeds the health criteria established by the competent health authorities as well as those established by the World Health Organization and the European Union, as established in the 140/2003 Royal Decree of 7 February, establishing the health criteria of quality drinking water.

Hard water is one that contains high levels of minerals, particularly calcium and magnesium salts. Although other minerals such as strontium, iron and manganese, also contribute to the hardening of the water, they do so to a lesser extent, since they are generally dissolved in water in small amounts.

Hard water is not harmful to health, but rather the opposite: it provides a significant percentage of the recommended daily intake of calcium and magnesium, and can prevent the onset of various diseases.

Water acquires calcium and magnesium, which determine its hardness, in contact with the various types of ground through which the river flows or from its source. Therefore the hardness of the water depends on the geological nature of the soil through which it passes from its origin. Thus a limestone soil generates higher lime content than a granite-based soil.

The hardness of the tap water poses no danger to human health, but the opposite: calcium and magnesium, which characterise the hardness of the water, are essential to health. Want to know more?

Water hardness is typically expressed by the concentration of calcium carbonate (CaCO3) water. Therefore, according to the degree of hardness, different classifications of water are used. One of the most commonly used is the Merck scale:

0-79 mg CaCO3/l …………………….…….…… Very soft water
80-149 mg CaCO3/l ………………………….…..….. Soft water
150-329 mg CaCO3/l …………………………. Semi-hard water
330-549 mg CaCO3/l ……………………………….. Hard water
More than 550 mg CaCO3/l ……………….……Very hard water

Water hardness can also be expressed in French degrees (° fH) or German degrees (° dH). The equivalence between these units and the hardness expressed in mg/l of calcium carbonate is as follows:

1 °fH = 10 mg CaCO3/l
1 °dH = 17.8 mg CaCO3/l

Actually the hardness of water is 440 mg CaCO3/L (44º fH)

The main advantages of hard water are:

  • Significant nutrients of the recommended daily intake of calcium and magnesium.
  • Lower incidence of cardiovascular disease and greater protection of the skeletal system, among other health benefits.
  • The protection of water pipes from corrosion.
  • Easier rinsing of soap.

The main disadvantages are:

  • The accumulation of scale deposits in pipes and household appliances.
  • The appearance of whitish residue on dishes.
  • May cause slightly dry skin and hair.