Purification of the water
The water from the tap or in the mineral water bottles in the store is not chemically clean. The water in the store that is next to being chemically clean is called distilled water and is intended for car batteries, irons and for other technical purposes. Do not drink it! It is not as dangerous as it was thought to be, but the mucous membranes of mouth and esophagus are irritated by it.
The closest to chemically clean water found in nature is rainwater some minutes after the rain began and before it reaches the ground. Formerly, when soap was used to wash the hair, and it was recommended to use rainwater for hair wash because it was so soft that no lime soap (insoluble smudge) was formed. Modern shampooing agents do not form lime soaps, so the problem has been solved without complicated collection of rainwater. But rainwater has been affected by acidification: instead of pH about 5 to 6, that was found before we polluted our environment, the pH is now about 3.5. The reason is primarily sulfuric acid from the combustion of coal and oil. The acidic water destroys architecture and artwork. It dissolves substances in soil and stone and thereby changes the composition of the water, both groundwater and surface water.
How well the municipal waterworks succeed in the treatment of the water partly depends on what pollution there is. Residues from plants or animals can be removed with simple processes. It is more difficult to remove gasoline, diesel, oils and fire protection agents. Therefore, traffic accidents must be prevented, and car wash and workshops be prohibited in areas from which water flows to municipal aquifers. Even a very small amount of gasoline will destroy the water in a large water supply for a long time. One must also be careful not to pump too much water from a water source so that salt water flows backwards from the ocean: a saltwater break through will destroy a water supply for a very long time.
The water we use, both surface water and groundwater, always contains larger or smaller amounts of other substances even if the water is clear and looks clean. Some of them are desired, other substances may not be desired but do not hurt, others more may be harmful, at least in large amounts. What substances are in the water depends on what has happened to the water between rain and delivery. Though we do not see them in the water they are visible as spots when water drops have dried for instance on glass surfaces.
You can divide the “substances” in the water into biological, organic and mineral (I do not write contaminants, some of them are highly desirable):
- The biological are fungi (microscopic), algae, bacteria and others. Most are completely innocent and harmless, a few are not desirable in the water.
- The organic is a mixture of very different substances: residues from the decomposition of plants, animals and excrements, technical products (motor fuels, mineral oils, detergents, fertilizers, plant protection products and others).
- The minerals are inorganic compounds, mostly salts of different metals.
The roads of the water
When the rain hits the ground, it can flow directly to a stream or to a lake. This water, surface water, contains no mineral salts, but it may have accumulated biological and organic pollutants on the road. Should it be used for household use, it must be cleaned and disinfected.
The rain water also flows into the ground. During the passage through soil and sand layers, some of the pollutants are removed and taken up by sand, rock and soil and by microorganisms in the soil and the sand. Dug wells (private) can often have good water quality, but there are also horrible examples of private wells. There are always microorganisms in the water, but in good wells none of them are harmful. If there are coli bacteria, it shows that water from manure well or similar leaks in, and such water must not be used as drinking water for humans or animals. Water from water bodies in loose soil can also be used after further purification as municipal water. Above all, if there is sand at the bottom, this may be very good water and at high capacity.
In the loose soils, the water accumulates in water courses where it flows like underground streams or waterways towards lakes or directly towards the sea. A large part of the water arrives to the sea without reaching the surface. In the early days, when digging wells, men believed to have magic power, dowsers, were used to find aquifers with their dowsing rods. It was said that branches cut in spring when the sap rose in the trees were especially useful as dowsing rods as they were thirsty and dragged down to the water in the ground. This is contradicted by the fact that dowsers also successfully used rods made from steel wire. The magic of successful dowsers was rather based on experience of how the water flows and on observations of what the country looks like, where there are different kinds of soil and where different plants grow (especially those with deep roots) and which hills and sinks may lead the waterways.
Some of the water flows into the rock. We tend to think that the rock is impermeable to water. It is not, in the rock there are both larger and smaller cracks down to microscopic pores. In the fractures and pores there are microorganisms that, among other things, consume biological and organic pollutants. As the water flows through the rock, it dissolves substances from the stone while the water is being cleaned. What substances are released depends on the rock, but the minerals that are dissolved are often salts (mostly carbonate and bicarbonate) of calcium and magnesium, the water becomes hard. Here in Majorca, much of the rock consists of limestone, and groundwater here is usually very hard. The limestone is quite porous so that much of the water flows down through the rock. In some cases where the mountain is steep, the water may flow out of the stone and form a mineral water source. In general, it is necessary to drill down to the aquifer and pump up the water.
Where does the tap water come from?
Water consumption in a densely populated area like Mallorca is so high that it is necessary to use water from different origins: surface water, groundwater from loose soil and water from the rock. To smooth the supply of water over the year between rainy and dry seasons, during the rainy season, water is collected in large cisterns, artificial lakes, from which water is pumped during dry periods. The water pipes in the different municipalities are therefore very different, hard and mineral rich in Tramuntana, softer in the municipalities of the plain, and it also changes during the year.
Municipal water and mineral water
First of all, tap water in all municipalities of Mallorca is fully suitable as drinking water. Many use mineral water in bottle as drinking water. This is because it tastes better, not because water from the tap would in any way be harmful.
The water that we drink is important not only to fill our need for water but also because it contains many minerals that are important to our health. Therefore, the content of different minerals in the water should be declared significantly better. This applies both to tap water and to bottled water – I have never found any analysis or declaration of municipal water and the declarations on the labels of mineral water bottles are misleading. Firstly, the analyzes are years old (if the time for the analysis is stated at all), secondly, they cover a few substances, often not the important ones. In the next blog I will summarize some facts about minerals in drinking water.<< Travelling on Mallorca