Water resources of the earth. Fresh water reserves on Earth: approximate volumes, the problem of water shortage, interesting facts

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Fresh water sources

Fresh water resources exist thanks to the eternal water cycle. As a result of evaporation, a gigantic volume of water is formed, reaching 525 thousand km 3 per year.

The rate of renewal determines the resources available to mankind. Most of the fresh water - 85% - is concentrated in the ice polar zones and glaciers. The rate of water exchange here is less than in the ocean, and is 8000 years. Surface water on land is renewed about 500 times faster than in the ocean. Even faster, in about 10 - 12 days, the waters of the rivers are renewed. Fresh waters of the rivers have the greatest practical value for mankind. Rivers have always been a source of fresh water. But in the modern era, they began to transport waste. Waste in the catchment area flows down the riverbeds into the seas and oceans. Most of the used river water is returned to rivers and reservoirs in the form of Wastewater. Fresh water reserves are potentially large. However, in any part of the world, they can be depleted due to unsustainable water use or pollution. The volume of water consumed depends on the region and standard of living and ranges from 3 to 700 liters per day per person. Water consumption by industry also depends on the economic development of the area. For example, in Canada, the industry consumes 84% ​​of the total water intake, and in India - 1%. The most water-intensive industries are: steel, chemical, petrochemical, pulp and paper, and food. They take almost 70% of all water used in industry. On average, industry consumes about 20% of all water consumed in the world. The main consumer of fresh water is agriculture: 70-80% of all fresh water is used for its needs.

The total runoff of the rivers of the CIS (USSR) for the year is 4720 km 3. But water resources are distributed extremely unevenly. In the most populated regions, where up to 80% of industrial production lives and 90% of land suitable for agriculture is located, the share of water resources is only 20%. Many parts of the country are not sufficiently supplied with water. This is the south and southeast of the European part of the CIS, the Caspian lowland, south Western Siberia and Kazakhstan, and some other areas Central Asia, south of Transbaikalia, Central Yakutia.

Groundwater group subdivided into:

1. Artesian waters, which, with the help of pumps, rise to the surface from underground space. They can lie underground in several layers or so-called tiers, which are completely protected from each other. The chemical composition of water, as a rule, remains constant.

2. Infiltration water. This water is extracted by pumps from wells, the depth of which corresponds to the marks of the bottom of a stream, river or lake.

3. Spring water. About underground water, self-flowing naturally to the surface of the earth.

surface water:

1. River water. River water is the most polluted and therefore the least suitable for drinking water supply purposes. It is polluted by the waste products of people and animals. In still more pollution of river waters occurs with incoming sewage from workshops and industrial enterprises. . The preparation of river water for the purposes of drinking water supply is also difficult due to strong fluctuations in river water pollution, both in quantitative terms and in composition.

2. Lake water. This water, even extracted from great depths, is extremely rarely biologically impeccable and therefore must undergo special purification to drinking standards.

3. Water from reservoirs. We are talking about water from small rivers and streams, which are dammed upstream, where the water is the least polluted. Reservoir water is categorized in the same way as Lake water. In all cases, when choosing the method and volume of necessary water treatment measures, the decisive factor is how much this water is polluted and how high the self-cleaning ability of this “storage” is. drinking water».

4. Sea water. Sea water cannot be supplied to the drinking water supply network without desalination. It is extracted and treated only near the sea coast and on the islands, if it is not possible to use another source of water supply.

The problem of water consumption. The main condition for human existence is the consumption of sufficient water. The current situation is due to the fact that surface waters are mainly used as water sources, which make up only 1% of all fresh water reserves on Earth. In addition, it has been found that within 1 year, 50% of the world's river flow passes through various human activities, which include domestic needs, industrial production and crop irrigation (

Human water consumption, km 3 /year

For most of the development of human civilization during the 18 centuries, the daily human requirement was limited to 5 to 49 liters per day. The main reason for the limited water consumption was the presence of pathogenic microbes that were the cause of epidemics:

Typhoid, cholera, dysentery, poliomyelitis, hepatitis, gastroenteritis due to consumption of contaminated drinking water.

· Trachoma, leprosy, and other diseases of the skin and mucous membranes when washing with contaminated water.

· Malaria, yellow fever, due to the presence of infection carriers in the water.

Drinking water consumption increased dramatically after the appearance of the first centralized water treatment systems in the 18th and 19th centuries in Europe and Russia and has now reached 200-300 liters per person per day.

However, in 1985, only 1.1 billion people were supplied with clean tap water at this level, while 0.8 billion people received 110 liters / day-person through standpipes, and the rest of humanity (4 billion) is content with a norm of 50-60 l/day-person. Nevertheless, in general, over the 20th century, human water consumption has increased by an average of 20 times. The main consumption of drinking water is associated with the observance of sanitary and hygienic standards. spring artesian water infiltration

Structure of water consumption for household purposes of the urban population

Thus, in order to provide the population drinking water, (in each region of the Russian Federation), it is necessary to solve the problem of water quality management both in water sources and at treatment facilities. Obviously, the choice of water treatment and wastewater treatment technology will be carried out by comparing water quality data with their characteristics.

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The main source of fresh water is atmospheric precipitation, but two other sources can also be used for consumer needs: groundwater and surface water.

Underground springs

Approximately 37.5 million km 3, or 98% of all fresh water in the liquid state falls on groundwater, and about 50% of it lies at depths of no more than 800 m. However, the volume of available groundwater is determined by the properties of aquifers and the capacity of pumping water pumps. Groundwater reserves in the Sahara are estimated at about 625 thousand km3. Under modern conditions, they are not replenished at the expense of surface fresh waters, but are depleted during pumping. Some of the deepest underground waters are never included in the general water cycle at all, and only in areas of active volcanism do such waters erupt in the form of steam. However, a significant amount of groundwater still penetrates the earth's surface: under the influence of gravity, these waters, moving along impermeable sloping rock layers, emerge at the foot of the slopes in the form of springs and streams. In addition, they are pumped out by pumps, and are also extracted by plant roots and then enter the atmosphere through the process of transpiration.

Fig.1. The exit of the underground source to the surface

The groundwater table represents the upper limit of available groundwater. In the presence of slopes, the groundwater table intersects with the earth's surface, and a source is formed. If groundwater is under high hydrostatic pressure, then artesian springs are formed in the places where they come to the surface. With the advent of powerful pumps and the development of modern drilling technology, the extraction of groundwater has become easier. Pumps are used to supply water to shallow wells installed in aquifers. However, in wells drilled in great depth, to the level of pressure artesian waters, the latter rise and saturate the overlying groundwater, and sometimes come to the surface. Groundwater moves slowly, at a speed of several meters per day or even per year. They are usually found in porous pebbly or sandy horizons or relatively impermeable shale layers, and only rarely are they concentrated in underground cavities or in underground streams. For the correct choice of a well drilling site, information about the geological structure of the territory is usually required.

In some parts of the world, the growing demand for groundwater is having serious consequences. The pumping out of a large volume of groundwater, incomparably greater than their natural replenishment, leads to a shortage of moisture, and lowering the level of these waters requires large expenditures on expensive electricity used to extract them. In places where the aquifer is depleted, the earth's surface begins to subside, and the restoration of water resources in a natural way is complicated there.

In coastal areas, excessive abstraction of groundwater leads to the replacement of fresh water in the aquifer with salt water, and thus the degradation of local fresh water sources occurs. Gradual deterioration of groundwater quality as a result of salt accumulation can have even more dangerous consequences. Salt sources can be both natural (for example, the dissolution and removal of minerals from soils) and anthropogenic (fertilization or excessive watering with water with a high salt content). Rivers fed by mountain glaciers usually contain less than 1 g/l of dissolved salts, but the salinity of water in other rivers reaches 9 g/l due to the fact that they drain areas composed of salt-bearing rocks for a long distance.

The indiscriminate release or disposal of toxic chemicals causes them to seep into aquifers that provide drinking or irrigation water. In some cases, just a few years or decades are enough for harmful chemical substances got into groundwater and accumulated there in tangible quantities. However, if an aquifer was once polluted, it would take 200 to 10,000 years for it to naturally clean itself.

surface sources

Only 0.01% of the total volume of fresh water in the liquid state is concentrated in rivers and streams and 1.47% in lakes. Dams have been built on many rivers to store water and provide it continuously to consumers, as well as to prevent unwanted floods and generate electricity. The Amazon in South America, the Congo (Zaire) in Africa, the Ganges with the Brahmaputra in South Asia, the Yangtze in China, the Yenisei in Russia, and the Mississippi with the Missouri in the USA have the highest average water consumption and, consequently, the highest energy potential.

Fig.2. Freshwater Lake Baikal

Natural freshwater lakes, containing about 125 thousand km 3 of water, along with rivers and artificial reservoirs, are an important source of drinking water for people and animals. They are also used for irrigation of agricultural land, navigation, recreation, fishing and, unfortunately, for the discharge of domestic and industrial wastewater. Sometimes, due to the gradual filling with sediments or salinization, the lakes dry up, but in the process of evolution of the hydrosphere, new lakes are formed in some places.

The water level even in "healthy" lakes can decrease during the year as a result of water flow through the rivers and streams flowing from them, due to water infiltration into the ground and its evaporation. The restoration of their level usually occurs due to precipitation and the inflow of fresh water from rivers and streams flowing into them, as well as from springs. However, as a result of evaporation, salts that come with river runoff accumulate. Therefore, after millennia, some lakes can become very salty and unsuitable for many living organisms.

Scientific and methodological substantiation.

Water is one of the most important elements of the external environment, necessary for the life of humans, animals and plants. Water is involved in the formation of the structural elements of the human body, is necessary for the normal course of physiological processes, heat balance with the environment. Loss of water in the amount of 10% of body weight leads to a noticeable metabolic disorder, a loss of 15-20% at air temperatures above 30 0 is already fatal, and a loss of 25% is fatal at lower air temperatures (E. Adolf) .

In addition to meeting physiological needs, a significant amount of water is spent on hygienic, household and industrial needs.

Water has always been regarded as an important factor in the transmission of many infectious diseases.

Water can fulfill its hygienic role only if it has the necessary quality, which is characterized by its organoleptic properties, chemical composition and the nature of the microflora.

In the Gomel region, for example, there are more than 2 thousand sources of centralized water supply, and only 188 (9%) sources of water do not require additional purification.

The main ingredients of drinking water pollution in the region are iron, manganese, salts that form the overall hardness, nitrates.

Water that does not meet hygienic requirements must be treated to bring its quality in line with the requirements of SanPiN.

STATE OF FRESH WATER SOURCES ON THE PLANET

Fresh water accounts for about 3.5% of the total water on Earth. Of these, river waters have a total volume of 1.2 x 10 3 km 3, underground - 6 x 10 4 km 3, lakes and reservoirs - 230 x 10 3 km 3, soil water - 82 x 10 3 km 3.

Traditionally, people get most of their fresh water for household, industry and irrigation from surface water bodies. To ensure a more stable water supply, dams are being built, reservoirs are being created, and irrigation canals are being carried out.

Each city in turn takes water from the river, purifies it, uses it to wash off the next batch of waste, and dumps it back into the river, often with minimal treatment. Thus, each next city must deal with more and more water pollution, and, naturally, the reservoir as an ecosystem suffers from this. Industrial waste exacerbates this situation, as large industrial enterprises, as a rule, are located on large rivers, lakes, bays.

The demand for fresh water is constantly growing. But the more water is taken, the stronger will be the drop in its level in the reservoir, and, especially, due to irrevocable water consumption (i.e. irrigation), because. water returns to the atmosphere due to evaporation and is lost for some time for this reservoir.

It is believed that more than 30% of the average annual river flow cannot be used. On a number of rivers, the water intake exceeds 90% of the average annual flow, so that a chronic lack of water is inevitable.

To increase water intake, it remains to use groundwater more intensively. At present, groundwater consumption is also outpacing recharge, causing groundwater levels to fall. And this, in turn, affects surface water bodies, because they are fed by springs, which are the outlet of groundwater to the surface.

When the water table drops, a gradual sinking of the land surface can occur, called ground subsidence. Sometimes this drawdown can be sudden, with catastrophic consequences.

Due to the depletion of groundwater, another problem arises - the inflow of salt water into fresh water bodies in coastal areas.

Ground water is of good quality and meets the requirements of the drinking water standard without additional treatment. Now, cases of contamination of high-quality groundwater with toxic substances and pathogenic microorganisms are becoming more frequent. Groundwater pollution is one of the environmental problems of the 20th century.

Let us dwell briefly on the main factors and sources of ecological trouble in the hydrosphere.

atmospheric waters.

All components of the biosphere are closely interconnected. The ecological state of the hydrosphere is directly related to the ecological state of the atmosphere and lithosphere.

Most pollutants from the atmosphere and lithosphere end up in the liquid phase, i.e. as part of the hydrosphere, and through it affect all levels of life.

The composition of rainwater that replenishes fresh water bodies affects aquatic ecosystems, and the composition of precipitation depends on the state of the atmosphere.

The following calculations are known: 1 raindrop weighing 50 mg, falling from a height of 1 km, washes 16 liters of air. This means that various pollutants will be easily washed out of the air. An example of this is the leaching of radioactive substances from the atmosphere, which led to patchy contamination of the territory of our republic after the Chernobyl accident. Many gaseous compounds, dissolving in atmospheric moisture, form acid precipitation, which disrupts the ecological balance of both terrestrial and aquatic ecosystems.

Water that falls to the ground in the form of precipitation can either be absorbed into the soil or run off. When it reaches the surface of the earth, rainwater captures soil particles, dissolved chemicals, and detritus with microorganisms that feed on it. Therefore, surface runoff can be heavily polluted. Most of the water is absorbed into the soil. Dirt particles, detritus and microorganisms are filtered out of it. However, dissolved chemical compounds are not retained by the soil, but are carried away by water. Therefore, any chemical applied, placed, spilled, spilled on or in contact with the ground can contaminate groundwater.

That is why the chemical composition of fresh water depends on the physical and geographical features of the area (the nature of the soil, soil, water exchange features and the ecological well-being of environmental objects).

HYGIENIC CHARACTERISTICS OF WATER SUPPLY SOURCES

One of the main fundamental issues of drinking water hygiene is the choice of water source. This choice is made by technical and economic comparison of options for water supply sources, which can be atmospheric, underground and surface.

Atmospheric waters are very weakly mineralized, very soft, contain little organic matter and are free from pathogenic bacteria. In the future, the quality of water is affected by the method of collection and storage.

Groundwater suitable for drinking water supply purposes lies at a depth of no more than 250 - 300 m. According to the conditions of occurrence distinguish between perched water, groundwater and interstratal water, significantly different from each other in terms of hygienic characteristics.

Groundwater, which lies closest to the earth's surface, is called perched water. Due to the surface occurrence, the lack of a waterproof roof and the small volume, the perch is easily polluted, as a rule, it is unreliable in sanitary terms and cannot be considered a good source of water supply.

Groundwater - the water of the first permanent aquifer from the surface of the earth. They do not have protection from waterproof layers; the area of ​​groundwater recharge coincides with the area of ​​their distribution.

Groundwater is characterized by a very unstable regime, which depends entirely on hydrometeorological factors, the frequency of precipitation and the abundance of precipitation. As a result, there are significant seasonal fluctuations in the standing level, chemical and bacterial composition of groundwater. Their stock is replenished due to infiltration of atmospheric precipitation or water of high-level nature rivers. In the process of infiltration, water is largely freed from organic and bacterial contamination; at the same time, its organoleptic properties also deteriorate. Groundwater is mainly used for countryside in the organization of well water supply.

Interstratal groundwater lie between water-resistant layers and, depending on the conditions of occurrence, can be pressure or non-pressure. Interstratal waters differ from ground waters by their low temperature (5-12 0) and the constancy of their composition. Usually they are transparent, colorless, odorless and tasteless.

Due to long-term filtration and the presence of a water-resistant roof that protects interstratal waters from pollution, the latter are characterized by an almost complete absence of microorganisms, and can be used for raw drinking. Interstratal water is extracted by constructing deep tubular and, less commonly, shaft wells.

A constant and large flow rate (from 1 to 200 m 3 / h) and good water quality make it possible to consider interstratal aquifers as best source water supply for small and medium-sized water pipelines, most of which supply water to the population without any treatment.

Springs. Groundwater can independently come to the surface of the earth. In this case, they are called springs, from which springs or streams are formed.

surface water flow down natural slopes to lower places, forming flowing and stagnant water bodies: streams, rivers, flowing and stagnant lakes. Open reservoirs are fed not only by atmospheric, but also partially by groundwater.

Open water bodies are subject to pollution from the outside, therefore, from an epidemiological point of view, all open water bodies are potentially dangerous to a greater or lesser extent. Water is especially heavily polluted in areas of the reservoir lying near settlements and in places where wastewater is discharged.

If necessary, use an open reservoir for water supply

it is necessary, firstly, to give preference to large and flowing unregulated reservoirs, secondly, to protect the reservoir from pollution by domestic and industrial wastewater and, thirdly, to reliably disinfect water.

In connection with the above on the hygienic characteristics of water sources of various origins, GOST provides, when choosing water supply sources, to focus primarily on pressure, interstratal-artesian waters. If it is impossible to use them, others are sought in the following order: a) interstratal pressure water, including spring water; b) groundwater; c) open water.

SANITARY PROTECTION OF WATER SUPPLY SOURCES.

In order to protect water sources from pollution, sanitary protection zones (SPZ) are organized, which have three belts.

The first zone of the ZSO of underground and surface sources of water supply and water supply facilities is established in order to eliminate the possibility of accidental or intentional contamination of the source water at the location of water intake and water supply facilities. Groundwater intakes should be located, as a rule, outside the territory of industrial enterprises and residential buildings. The first ZSO belt is installed at a distance of at least 30 m from the water intake - when using protected groundwater and at a distance of at least 50 m - when using insufficiently protected groundwater. When using a group of underground water intakes, the boundary of the first belt should be located at a distance of at least 30 m and 50 m, respectively, from the outermost wells (or shaft wells).

The boundary of the second zone of the WSS is determined by hydrodynamic calculations, based on the conditions that if microbial /unstable/ pollution enters the water pumping horizon outside it, they do not reach the water intake. To effectively protect an underground water supply source from microbial (unstable) pollution, it is necessary that the estimated time for the movement of pollution with groundwater from the boundaries of the second belt to the water intake is sufficient for the loss of viability and virulence of pathogenic microorganisms, i.e. for effective self-cleaning.

The boundary of the third zone of the ZSO is determined by hydrodynamic calculations, based on the condition that if outside it in the water pumping horizon

When chemical (stable) pollution enters the umbrella, they either do not reach the water intake, moving with groundwater outside the recharge area, or reach the water intake, but not earlier than the estimated time.

The water supply scheme determines the mutual, technologically linked location of the water supply system facilities and the procedure for supplying water from the source and consumption. The choice of scheme depends on the source of water supply, the requirements for the quantity and quality of water, the reliability and survivability of the water supply system, the terrain and other features.

Drinking water in all cases must be safe in terms of epidemics, harmless to chemical composition and have favorable organoleptic properties, i.e. must meet the hygienic requirements of GOST 2874-82 "Drinking water".

2. Hygienic requirements for the quality of drinking water (centralized water supply):

Comply with all organoleptic properties: be transparent, colorless, tasteless, odorless, contain no visible impurities, precipitation.

Water must be harmless in chemical composition, free of carcinogenic, radioactive and harmful chemicals.

Water must be safe in terms of epidemic and radiation, not contain pathogenic bacteria, viruses, protozoa, helminth eggs, and correspond in terms of  and β activity.

With decentralized water supply, organoleptic properties are allowed up to 3 points, nitrates are not more than 45 mg / l, the number of bacteria of the Escherichia coli group (coli-index) by the number of BGKP in 1000 ml of water is not more than 10.

The main sources of water pollution in our country are the Zhlobin metallurgical plant BMZ, the Rechitsa hydrolysis plant. Controls the quality of water - Gomel water utility.

Often, the same method can be used to solve several problems of improving water quality. For example, the filtration method can achieve water clarification, partial disinfection, neutralization, etc.

Clarification and discoloration of water is to free it from substances that cause turbidity and color. This is achieved by settling, filtering through porous materials and coagulation. Very often these methods are used in combination with each other. For example, sedimentation with filtration or coagulation with sedimentation and filtration.

As part of most water treatment plants, there are special facilities called sedimentation tanks. According to the flow structure, sedimentation tanks are conditionally divided into horizontal, radial and vertical. The waters in them move at a very low speed, due to which conditions are created for the settling of many particles of a certain degree of dispersion and specific gravity. In this case, small particles often agglomerate (enlarge) and also acquire the ability to settle. To speed up this process, some settling tanks are equipped with so-called modules, which are systems of parallel shelves (each 20–40 cm high), which shorten the path of particles to the bottom of the shelf, which significantly increases the capacity of the settling tanks.

With prolonged settling, which often occurs in natural conditions (ponds, reservoirs), not only an increase in transparency is observed, but also the color decreases, as well as the number of microorganisms (according to Khlopin by 75–90%).

The process of filtering water consists in passing it through some porous or fine-grained material. Sand, coal, slag, anthracite chips, sawdust, fabric, porcelain, etc. are used as a filter material.

On the surface of the filter and partly in the thickness there is a retention of suspended solids, some of the microorganisms and, depending on the nature of the filter material, the sorption of chemicals.

Water is life. And if a person can survive for a while without food, it is almost impossible to do this without water. Since the heyday of engineering, the water production industry has become too fast and without special attention contaminated by humans. Then the first calls about the importance of the preservation of water resources appeared. And if, in general, there is enough water, then the fresh water reserves on Earth make up a negligible fraction of this volume. Let's deal with this issue together.

Water: how much is it, and in what form does it exist

Water is an important part of our life. And it is she who makes up most of our planet. Mankind uses this extremely important resource on a daily basis: household needs, production needs, agricultural work and much more.

We used to think that water has one state, but in fact it has three forms:

• liquid;
• gas/steam;
• solid state (ice);

In a liquid state, it is found in all water basins on the surface of the Earth (rivers, lakes, seas, oceans) and in the bowels of the soil (groundwater). In the solid state, we see it in snow and ice. In gaseous form, it appears in the form of clouds of steam, clouds.

For these reasons, it is problematic to calculate what is the supply of fresh water on Earth. But according to preliminary data, the total volume of water is about 1.386 billion cubic kilometers. Moreover, 97.5% is salty water(undrinkable) and only 2.5% is fresh.

Fresh water resources on earth

The largest accumulation of fresh water is concentrated in the glaciers and snows of the Arctic and Antarctica (68.7%). Next come groundwater (29.9%) and only an incredibly small part (0.26%) is concentrated in rivers and lakes. It is from there that mankind draws the water resources necessary for life.

The global water cycle changes regularly, and from this numerical values change also. But in general, the picture looks exactly like this. The main reserves of fresh water on Earth are in glaciers, snow and groundwater, and its extraction from these sources is very problematic. Perhaps, in the not distant future, mankind will have to turn their eyes to these sources of fresh water.

Where is the most fresh water?

Let us consider in more detail the sources of fresh water, and find out which part of the planet has the most of it:

• Snow and ice at the North Pole is 1/10 of the total fresh water reserve.
• Groundwater today also serves as one of the main sources for the extraction of water.
• Lakes and rivers with fresh water, as a rule, are located at high elevations. This water basin contains the main reserves of fresh water on Earth. Canada's lakes contain 50% of the world's total freshwater lakes.
• River systems cover about 45% of the land of our planet. Their number is 263 units water basin suitable for drinking.

From the above, it becomes obvious that the distribution of fresh water reserves is uneven. Somewhere there is more of it, and somewhere it is negligible. There is one more corner of the planet (except Canada), where the largest reserves of fresh water on Earth. These are the countries Latin America, 1/3 of the total world volume is located here.

The largest freshwater lake is Baikal. It is located in our country and is protected by the state, listed in the Red Book.

Scarcity of usable water

If we go from the opposite, then the mainland that most of all needs life-giving moisture is Africa. Many countries are concentrated here, and all have the same problem with the water resource. In some areas it is extremely scarce, and in others it simply does not exist. Where the rivers flow, the quality of the water leaves much to be desired, it is at a very low level.

For these reasons, more than half a million people do not receive water of the required quality, and, as a result, suffer from many infectious diseases. According to statistics, 80% of cases of diseases are associated with the quality of the fluid consumed.

Sources of water pollution

Water conservation measures are a strategically important part of our lives. The supply of fresh water is not an inexhaustible resource. And, moreover, its value is small relative to the total volume of all waters. Consider the sources of pollution to know how you can reduce or minimize these factors:

• Wastewater. Numerous rivers and lakes were destroyed by sewage from various industrial productions, from houses and apartments (household slag), from agro-industrial complexes and much more.
• Burial of household waste and equipment in the seas and oceans. Very often practiced similar view disposal of rockets and other space instruments that have served their time. It is worth considering that living organisms live in reservoirs, and this greatly affects their health and water quality.
• Industry ranks first among the causes of water pollution and the entire ecosystem as a whole.
• Radioactive substances, spreading through water bodies, infect flora and fauna, make water unsuitable for drinking, as well as the life of organisms.
• Leakage of oily products. Over time, metal containers in which oil is stored or transported are subject to corrosion, respectively, water pollution is the result of this. Atmospheric precipitation containing acids can affect the state of the reservoir.

There are many more sources, the most common of them are described here. In order to keep fresh water supplies on Earth as long as possible suitable for consumption, they must be taken care of now.

Water reserve in the bowels of the planet

We have already found out that the largest reserve of drinking water is in glaciers, snows and in the soil of our planet. In the bowels of fresh water reserves on Earth are 1.3 billion cubic kilometers. But, in addition to the difficulties in obtaining it, we are faced with problems that are associated with its chemical properties. Water is not always fresh, sometimes its salinity reaches 250 grams per 1 liter. Most often there are waters with a predominance of chlorine and sodium in their composition, less often - with sodium and calcium or sodium and magnesium. Fresh groundwater is located closer to the surface, and at a depth of up to 2 kilometers, salt water is most often found.

What are we using this precious resource for?

We use almost 70% of our water to support the agricultural industry. In each region, this value fluctuates in different ranges. About 22% we spend on all world production. And only 8% of the rest goes to household needs.

A decrease in the water reserve of drinking water threatens more than 80 countries. It has a significant impact not only on social, but also economic well-being. It is necessary to look for a solution to this issue now. Thus, reduced consumption of drinking water is not a solution, but only exacerbates the problem. Every year, the fresh water supply decreases to a value of 0.3%, while not all sources of fresh water are available to us.

So that you can imagine how much and what kind of water is on our planet, I bring to your attention Table. 2.1. We have so much water that it is extremely inconvenient to measure it in liters, cubic meters or tons, and we will use a truly titanic measure - a cubic kilometer (km?). The total water on Earth is about one and a half billion, or 1500 million km? water.

Table 2.1. Distribution of waters on the globe (unit of measurement - million cubic kilometers)

Note. The data in the table are given by minimum and maximum, taking into account different estimates.

So, we see that fresh water, that is, water on land and in the atmosphere, is about 10% of the total planetary resource. Most of them - and this may be surprising - are not in open water bodies, but in the earth's crust: 110-190 million km ?! These waters are usually divided into two types according to their depth. Deep underground waters are located tens to hundreds of meters from the earth's surface, they impregnate porous rocks, and also form giant underground pools surrounded by waterproof layers. Often the water in these underground cavities is under pressure, and if you make your way to them with a drilling rig, the water will splash upwards in a fountain. Such geyser-fountains and springs of natural origin are well known.

Another type of groundwater is those that are located in the soil and upper layers of the earth's surface at a depth of several meters. Compared to deep waters, they have one disadvantage and one advantage. Flaw: these waters are much more actively in contact with the surface of the earth and everything that is poured onto it, thrown away or buried in it; they are much less protected from pollution than deep waters. Advantage: these waters are much more accessible to us, they act in any pit or ditch, and we can draw them from wells.

The next largest body of fresh water (20–30 million km?) is concentrated in the glaciers of Antarctica, Greenland and the North Islands. Arctic Ocean. We get fresh water from the atmosphere (only 13 thousand km?) in the form of precipitation - rain and snow. The main supply of fresh water used by man is concentrated in lakes and rivers, and it must be borne in mind that, although rivers are longer than lakes, their volume is much smaller. In living organisms, that is, in plants and animals (which, let me remind you, two-thirds are water), contains 6 thousand km? water - a value quite comparable with the volume of rivers. The latter should not be surprising: the one-time volume of rivers is static, and if we consider the dynamics, then only the rivers of Russia carry 4 thousand km into the ocean per year? water.

This is how water resources are distributed on our planet. After analyzing the data in the table, we can conclude that for drinking, domestic and industrial needs, the waters of lakes and rivers are more accessible, first of all, supplying us with fresh water not from time to time, but constantly and with a guarantee. In addition, we can easily evaluate and compare these reserves with our current and future needs.

Both types of groundwater are also available. However, for large cities, groundwater is not enough. In principle, it is possible to explore large deep basins and drill wells, but this is expensive. Besides, who guarantees that such a pool will be found near a populated industrial city? Will the water in it be suitable for drinking, and will there not be a geological catastrophe if we begin to withdraw this water in large quantities?

Precipitation, i.e. rain and snow, are also sources of fresh water. But this is a fickle, capricious source that mainly satisfies the needs of agriculture.

This means that rivers and lakes still remain, and at the same time, rivers are more convenient for us than lakes: there is less water in them, but, as I already mentioned, they are much longer. In fact, most of our civilization is concentrated in the river valleys - a circumstance that has remained unchanged since the days of Ancient Egypt, Akkad and Sumer.

Fresh water types

Before proceeding to consider the types of fresh water, let's dwell on their main purpose: they are a source of thirst quenching. When it overtakes us, we can think of nothing but water. Then any fresh water - even from a dirty river, even from a puddle - becomes drinking water for us. If we cannot satisfy our thirst within a few days, we will be doomed. The number of days is determined by the weather and climate: hot, dry or humid.

We, like any animals, are in a state of continuous water exchange with the environment: we emit sweat and urine and replenish water losses with fresh moisture. If it is not possible to get drunk, then water is lost through sweat and exhaled air, and as a result, there is a threat of dehydration (dehydration) of the body. At the first stage, the pulse quickens, weakness occurs, then dizziness and shortness of breath. With dehydration, which is only 10% of body weight, there will be a violation of speech, vision and hearing, then - delirium, hallucinations and loss of consciousness. Death occurs from irreversible changes in the nervous and cardiovascular systems with water loss of 15–25% of body weight (depending on ambient temperature).

Such is death from thirst, and it is all the more tragic when it occurs in the sea or in an ocean full of water - but salty! However, many probably remember the journey of Alain Bombard, a French explorer who swam Atlantic Ocean in an inflatable boat and quenched his thirst with sea water and juice squeezed out of fish. Is it possible? As an exception - yes! But only as an exception, as a way to save your life in an emergency, because for a long time we cannot drink salt water.

In sea and ocean water, calcium sulfate and carbonate, chloride, sulfate and magnesium bromide are present, but in small quantities. Nearly 85% of sea and ocean salts are sodium chloride, common table salt. By saturation with salts, water is different in different seas and oceans. I felt it first hand, swimming in the Baltic, Black and mediterranean seas. The Gulf of Finland is almost freshwater: in 1 liter of its water there are 3-4 g of salts, in the Black Sea - 15-18 g / l, in the ocean - up to 35 g / l, and, for example, in the Red Sea - 40 g / l. It's comfortable to swim, but you can't drink. Salts of potassium, sodium, magnesium, calcium and other elements are vital for a person, but in moderate doses. We cannot drink water with a salt content of more than 2.5 g/l.

Why? To maintain salt balance in the body, a person needs 15-25 g of salt per day - mainly NaCl, which we get from food. With an excess, salt is excreted in the urine through the kidneys, but to remove one extra gram of salt, you need to drink 100 g of water.

Well, now you are convinced that without water, as the song says, “not there and not here”? Just need to clarify - without fresh water.

In chapter 1, I mentioned that fresh water can be divided into two groups: ordinary and mineral. Moreover, within each group, water differs greatly in composition due to geological and geographical reasons. This classification is valid for waters of natural origin, but, in addition to them, there are artificial waters created by man purposefully or as waste. economic activity. We purposefully produce artificial mineral waters, desalinated water (from sea water) and distilled water, as well as special waters saturated with one or another component, for example silver. As for liquid waste, they are called drains, discharges and wastewater. Of course wastewater cannot be attributed to either fresh or salty marine, but within the framework of this book, we need to familiarize ourselves with them. So, if we take into account all these groups of waters, then our primary classification will be more or less complete. Let's start with distilled water.

Distilled water

Distilled water is pure H?O, or more precisely, water with negligible, almost indeterminate chemical and physical methods impurities of foreign substances. It is used only for medical or research purposes, for example, in order to wash test tubes for fine chemical experiments. It is produced by evaporating ordinary fresh water and then condensing the steam. In the same way, we can do with sea water to rid it of salts and mineral inclusions. Distilled water can be produced at home by making a homemade distiller or by purchasing a special installation. But I do not advise you to do this - distilled water is completely useless for us: it does not support vital processes in the human and animal body. As has been mentioned more than once, the drinking water we need is not at all an ideally pure substrate, but a solution containing mineral additives. In these additives - iron, copper, salts of sodium, potassium, calcium and other elements - the main essence. If we do not get them in the right amount through water, various functional disorders will occur: heart rhythm disturbances, headaches, muscle cramps, as well as problems with teeth and bone tissues. In a word, distilled water, which does not contain salts, can unbalance the work of our body.

They drink distilled water, compensating for the lack of the necessary substances in it with a special diet, a raw food diet, vegetables, fruits, microelement preparations, etc. This is the option proposed by the world-famous nutritionist Paul Bragg. Today, this idea has become even more constructive: for example, companies have appeared in the West that supply distilled water for drinking, and tablets with a full range of vital mineral substances accompany it. I drank some water with a pill - and eat as you like, without any diets.

However, we will not experiment, we will obey nature and drink the water of rivers, lakes and springs - the water that our ancestors drank. Let's just clean it up first.

Ordinary fresh water

As already mentioned, the fresh waters of rivers and lakes, our main source of water supply, are different. These differences arose initially and are associated with climate zone and features of the area in which the reservoir is located. Water is a universal solvent, which means that its mineral content depends on the soil and the underlying rocks. In addition, water is mobile, and, therefore, its composition is affected by precipitation, snowmelt, floods and tributaries flowing into more big river or a lake. Take, for example, the Neva, the main source of drinking water in St. Petersburg: it is mainly fed by Lake Ladoga, one of the freshest lakes in the world. Ladoga water contains little calcium and magnesium salts, which makes it very soft, there is little aluminum, manganese and nickel in it, but quite a lot of nitrogen, oxygen, silicon, and phosphorus. Finally, the microbiological composition of water depends on aquatic flora and fauna, from forests and meadows on the banks of the reservoir, and from many other reasons, not excluding factors of a cosmic nature. Thus, the pathogenicity of microbes increases sharply during the years of solar activity: previously almost harmless ones become dangerous, and dangerous ones become simply deadly.

I, a third generation Petersburger, drank fresh water from the Dnieper and Volga, from the Don and Kuban, drank water in Moscow, Norilsk, Irkutsk, Vladivostok, Prague, New York, Berlin and in many other places, but all this water is for with the possible exception of water. south coast Crimea, seemed to me unusual and tasteless. Is it a coincidence? Apparently not. Our body is adapted to the water of the motherland, it impregnates, shapes us, and there is none tastier and sweeter, but on condition that it is pure.

The concept of purity, if we recall the diversity of fresh waters, is actually very ambiguous. (The next chapter will present Russian and foreign standards for drinking water.) There are several important indicators of the quality of fresh natural water: acidity pH (or pH value), rigidity and organoleptic.

pH is related to the concentration of hydrogen ions in the environment, is measured using a simple device "ph-meter" and gives us the concept of acidic or alkaline properties of the environment (in this case- water):

pH< 7 – кислая среда;

pH = 7 - neutral environment;

pH > 7 - alkaline environment.

This is a very important indicator, not only for ordinary or mineral water, but also for human body, whose acid balance must be maintained within very strict limits: the permissible pH values ​​\u200b\u200bare from 7.38 to 7.42 and cannot deviate even by 10% from this range. At pH = 7.05, a person falls into a pre-coma state, at pH = 7.00 coma occurs, and at pH = 6.80 death occurs.

Rigidity called the property of water, due to the content of calcium ions Ca 2+ and magnesium Mg 2+ in it. Hardness is determined according to a special method described in GOSTs for drinking water, and the units of its measurement are moles per cubic meter (mol / m3) or millimoles per liter (mmol / l).

There are several types of hardness - general, carbonate, non-carbonate, removable and irremovable; later we will talk about total hardness associated with the sum of the concentrations of calcium and magnesium ions.

Under organoleptic The characteristics of water are its smell, taste, color and turbidity. Smell determine by smelling the water (earthy, chlorine, the smell of petroleum products, etc.) and evaluating the intensity of the smell on a five-point scale (zero corresponds to total absence smell):

1 - very weak, almost imperceptible smell;

2 - the smell is weak, noticeable only if you pay attention to it;

3 - the smell is easily noticed and causes a disapproving review of the water;

4 - the smell is distinct, attracts attention and makes you refrain from drinking;

5 - the smell is so strong that it makes the water unusable.

Taste water is characterized by the definitions of salty, sour, sweet, bitter, and all other taste sensations are called smacks. The taste is evaluated on the same five-point scale as the smell, with gradations: very weak, weak, noticeable, distinct, very strong. Colour water is determined photometrically by comparing the test water with reference solutions that mimic the color of natural water. The color is evaluated according to a special color scale with gradations from zero to 14. In a similar way, turbidity.

Of course, the causes that cause bad smell, bad taste and strange color of water are studied by chemical analysis methods to identify harmful impurities and determine their concentration. To complete this topic, let me remind you that each such impurity has its own MPC - the maximum permissible concentration, that is, one that does not harm our body. Of course, there are substances, viruses and bacteria, for which the MPC is zero, that is, they should not be in the water at all. But this is not a mathematical, but a “practical” zero - harmful substances and microflora may be present, but in such an insignificant concentration that they cannot be determined by the most subtle and accurate methods of analysis.

In addition to lakes and rivers, we get ordinary fresh water from wells, artesian wells, springs, and also by collecting precipitation, filling buckets and barrels with rainwater, or melting ice and snow. Let's talk about the first three varieties of water.

well water. Wells are actually used only in rural areas, since a pit with a depth of 5-10 m is not able to provide a large output of water - for this it is necessary to drill wells of 20-180 m, depending on the depth of groundwater. Wells are fed by underground waters and can provide water consumption up to 100-150 l/h (in rare cases - up to 500 l/h). They are very vulnerable in terms of pollution: everything that gets into the soil - nitrates, nitrites, surfactants, pesticides and heavy metals - can end up in well water.

Water from artesian wells. As I have already noted, deep-lying waters are better protected from various industrial and bacterial pollution, but it is difficult to use such waters in the city: firstly, you need to find them, and secondly, drill a well. This is expensive pleasure: special rigs are used for drilling, then they are lowered into the well steel pipes, a powerful pump is immersed, and a pipeline is already brought to the surface from it. There are two aquifers in the central regions of Russia: the sandy one lies at a depth of 15–40 m and is separated from the upper soil layer by clay layers, which protect it from pollution, and at a depth of 30–230 m or more there are limestone aquifers, the so-called artesian. That's how much you need to drill, and then, when you get to the water, check whether it is good and does not require cleaning. It is known that the composition of artesian waters depends on the depth of their occurrence. Such water may have increased hardness and contain bacteria and organic matter. In addition, due to poor pipe connections in wells, contaminants from higher aquifers can seep into artesian water. Usually this water needs to be filtered and purified, which is done with industrial rather than domestic purification systems.

Spring and spring water. Under a spring, or key, unlike a stream, a river and a river, is understood as a small water stream that beats directly from the bowels of the earth. It is appropriate to recall that some of our rivers are generated by mountain snows and glaciers, and some by such underground sources. However, at a considerable distance from them, river water can no longer be recognized as spring water. Spring moisture is taken in the very place where it comes from under the ground. Water can be fresh or mineralized. In the first case, we are, in fact, talking about springs and springs, and in the second - about the source of mineral waters.

The nature of spring water is the same as that of well or artesian water, since it comes from some kind of underground aquifer or basin.

On the territory of Russia, the number of springs is incalculable, they differ in the quality and composition of the waters. There are legends about the springs - and the waters of many really have healing properties, they are fresh and pleasant to the taste. But springs, just like artesian wells and wells, are subject to pollution. Nowadays, it is impossible to guarantee the constant quality of spring water, since it depends not only on seasonal circumstances (rainstorms, floods), but also on emissions from nearby industrial enterprises.

For example, spring water within the city limits in Nizhny Novgorod, about which the local sanitary and epidemiological supervision officially notified the population. The conducted studies have shown that the unfortunate location and inconvenience of springs, the insecurity of groundwater from surface contamination are the causes of poor water quality. In springs located near Blagoveshchensk and Caves monasteries, Vysokovskaya church, Pokhvalinsky congress, the content of nitrates exceeds the permissible norms by 1.5–3 times, and microbiological contamination significantly exceeds the MPC. Naturally, the sanitary service forbade the use of such water.

The situation is similar in other cities. In Moscow, there are only a few sources left from which you can drink water: the spring "Sergiy Radonezhsky" in Teply Stan, "Saint" in Krylatsky, "The Swan Princess" in Pokrovsky-Streshnev, "Tsaritsyno" in the floodplain of Tsaritsynsky Pond. Some of the popular springs from ancient times were closed: in the water of the spring in Troparevsky Park, the MPC for chromium was exceeded, in the Filevsky spring - for aluminum, potassium, magnesium, in the key of the Life-Giving Trinity in Borisov - an excess of iron, in springs in Sviblov (in the floodplain of the Yauza) and " Kadochka (in Kolomenskoye) the excess of the MPC for heavy metals, and in Beket in Donskoy - for cadmium and chromium. All these springs were widely known and popular, they were used (and, despite the ban, still continue to be used) by hundreds of residents, and therefore the initiators of such checks were found. But somewhere in the outback they still draw water from ancestral sources that have long been clogged, and only medical and environmental studies can reveal the connection between poor water quality and an increase in the number of people suffering from urolithiasis, diseases of the digestive tract and cardiovascular system.

Currently, cities sell bottled water, both spring and mineral. For example, in St. Petersburg, one of the largest suppliers of such water is joint-stock company"Polustrovo". I would like to hope that the springs and wells from which this water is taken lie far from urban underground utilities, all kinds of dumps and other sources of contamination, and that the composition of the water is regularly monitored by the sanitary service. I would also like to hope for the good faith of the suppliers of spring and mineral water and to be sure that we are not sold tap water passed through the Geyser or Aquaphor filter. After all, if there is fake vodka, why not fake bottled water?

Mineral water

Natural water with a high content of mineral components is classified into four groups.

1. Mineral medicinal waters with a total mineralization of more than 8 g/l. This also includes less mineralized water containing an increased amount of boron, arsenic and other elements. It is taken only as prescribed by a doctor.

2. Mineral medicinal table waters with a total mineralization of 2–8 g/l. They apply with medicinal purposes as prescribed by a doctor, but you can use them as a table drink.

3. Mineral table water with a mineralization of 1–2 g/l.

4. Table water with mineralization less than 1 g/l.

Mineral waters owe their origin, as a rule, to underground aquifers or pools located among special rocks, enriching the water with healing minerals over a long period, which dissociate in solution into positively charged cations and negatively charged anions.

In the name of the waters, the definitions “hydrocarbonate” and “sodium” may appear, which means that these substances are most common, but there may be waters of chloride-sodium-calcium, chloride-sulfate, sodium-magnesium, etc. Depending on what indicator the water has pH (that is, what charge ions predominate), mineral water is acidic, neutral or alkaline. The effect of each on the gastrointestinal tract and the body as a whole will be different. O medicinal properties quite a lot has been written about these waters, about what diseases and how to take them, and for this information I will refer readers to special literature. For example, to a large article by G.Z. Magazanika "The use of mineral waters at home", published in the collection.

artificial water

Under artificial I understand fresh water, made with the help of various technological tricks with the aim of either copying what is produced by nature, or creating something that has no analogue in nature. Desalinated sea ​​water, which is produced on a large scale United Arab Emirates, rich in oil, but poor in fresh water, can also be considered artificial, as well as heavy water obtained for research in the field of nuclear physics, but we will not dwell on this subject. You can make artificial mineral water or fake it, but we are not too interested in this either: we will turn to water with miraculous properties - melted, shungite, silver, "alive" and "dead". And having turned, we will find out that in this area there is truth, half-truth and whole piles of fantasies and lies.

Melt water. Of course, it can be obtained by melting snow or ice in a saucepan, but I do not advise doing this, especially for city dwellers. There is such a compound - benzo (a) pyrene, carcinogenic organic compound the first class of danger (carcinogenic - that is, leading to cancer). The main sources of environmental pollution with benzo(a)pyrene are aluminum production and transport aerosols (simply car exhaust gases). As studies by ecologists have shown, in dust and snow on the street or near a suburban highway, the amount of benzo (a) pyrene is tens of times higher than the MPC. Melting water from such snow is like pouring potassium cyanide into tea instead of sugar. Natural meltwater will wash it into reservoirs, and there it will dilute to such an insignificant concentration that it cannot be detected with the help of the most subtle analyzes. But the snow on the roads is better not to touch.

A home-made method for preparing melted, or frozen-thawed, water is described in Appendix 1. After reading it, you will see that this technology helps to purify drinking water from some harmful impurities and, possibly, informs it beneficial features. The question, however, is that along with heavy metals, useful macro- and microelements can go away.

shungite water. Shungite- rock, extensive deposits of which are located in the area of ​​Lake Onega, and in these deposits circulate and seep to the surface of the water, saturated with healing shungite emanation. Even Peter I built the first balneary in Russia in these places, and it still exists - the Marcial Waters resort near Petrozavodsk. There is a sanatorium where they are treated with water, very saturated with iron.

But how effective is artificial shungite water, which is prepared using household shungite filters? The filter is small in size, the water is in short-term contact with the mineral substance. In addition, this contact is by no means of the property that is realized in nature. Does water have time - and can it in principle - become curative? Big question! As for its purification from harmful impurities, there are even more questions.

In the book by O.A. Rysyev "Shungite - a stone of health" it is reported that St. Petersburg enterprises that produce shungite filters, at the same time produce magic pyramids of shungite, the so-called "Pharaoh's rods", bags stuffed with shungite, which must be placed under the bed to protect themselves from the harmful effects of geopathogenic zones. A map of the zones is attached, and, judging by it, Petersburgers do not have long to live - of course, if they are not saved by shungite. Such tales cause distrust both in artificial shungite water and shungite filters. But if you like curiosities and miracles, then read Rysyev's book, as well as another one by Y. Doronina "Shungite - a stone-savior". But the filter is still better to purchase "aquaphor", "geyser" or "barrier". Firms with a narrow specialization, which produce only filters, without any magic rods and pyramids, have more confidence.

silver water. You can read about its properties in a number of books and publications (see, for example,). In our list of artificial waters, it is the most trustworthy, since the bactericidal properties of silver have been known since ancient times. Also in ancient india with the help of this metal, water was disinfected, and the Persian king Cyrus stored water in silver vessels. The bactericidal properties of silver are confirmed by modern science.

The pioneer of research in this area is considered to be the French physician Benier Crede, who late XIX century reported success in the treatment of sepsis with silver ions. Continuing his research, he found out that silver kills diphtheria bacillus within three days, staphylococcus within two days, and the causative agent of typhoid fever within a day. At that time, Crede's results made a sensation in the scientific world and drew attention to this method of healing ailments.

In 1942, the Englishman R. Benton managed to stop the epidemic of cholera and dysentery that raged on the construction of the Burma-Assam road. Benton arranged for the supply of workers (and there were 30 thousand people) with clean drinking water, disinfected by electrolytic dissolution of silver (concentration 0.01 mg / l). Of course, other means were also used for this, but it is believed that the use of silver water played a decisive role.

When the bactericidal properties of silver were studied, it turned out that the decisive role here is played not by atoms, but by positively charged Ag + ions. (Let me remind readers that ionization, discussed in Chapter 1, increases the activity of substances in aqueous solutions.) Silver cations inhibit the activity of the enzyme that provides oxygen exchange in the simplest microorganisms, in other words, they "suffocate" pathogenic bacteria, viruses, fungi (in this "deadly » a list of about 700 species of pathogenic "flora" and "fauna"). The rate of destruction depends on the concentration of silver ions in the solution: for example, E. coli dies after 3 minutes at a concentration of 1 mg/l, after 20 minutes at 0.5 mg/l, after 50 minutes at 0.2 mg/l, after 2 hours - at 0.05 mg / l. It was found that the disinfecting ability of silver is higher than that of carbolic acid, sublimate, and even such strong oxidizing agents as chlorine, bleach, sodium hypochlorite. A logical question arises: why are chlorination, fluoridation and more used at water treatment plants? modern method- ozonation, and not electrolytic saturation of water with silver ions? This question is followed by an equally logical answer: expensive. Still, silver is a precious metal ... In addition, let's not forget that silver is heavy metal, and its saturated solutions are by no means useful to humans: the maximum permissible concentration is 0.05 mg / l.

When taking 2 g of silver salts, toxic effects occur, and at a dose of 10 g, it is likely fatal outcome. In addition, if a reasonable dosage is exceeded for several months, a gradual accumulation of metal in the body is possible.

Silver is an important trace element for us, necessary for the normal functioning of the endocrine glands, brain and liver. But I repeat once again: this fact is not a reason to get carried away with drinking silver water with a high concentration of ions.

As for the silver water with the above concentration of ions, it can be drunk regularly and constantly (for example, cosmonauts drink it during the period of duty on space station). It is very difficult to prepare silver water at home. If you infuse water in a silver vessel, the effect will be negligible. Silver water is produced in special electric ionizers and sold in stores (although there may be doubts whether it is really silver). It can also be obtained using the "Penguin" and "Dolphin" installations, which will be described in the fifth chapter.

"Living" and "dead" water. By these terms one can understand not only life-giving and destructive water from Russian folk tales, but also something more specific.

"Living" and "dead" water was first received by the inventor Kratov (see publications), who healed with their help from adenoma and sciatica. These liquids are produced by electrolysis of ordinary water, and sour water, which is collected at a positively charged anode, is called "dead", and alkaline(it is concentrated near the negative cathode) - "live". Judging by the descriptions in the literature, “living” water is soft, light, with an alkaline taste, sometimes with a white sediment; its pH = 10–11 units. “Dead” water is brownish, sour, with a characteristic odor and pH = 4–5 units. The industry already produces plants for electrolysis at home (“STEL”, with a capacity of up to 60 l / h, and less productive, but convenient “Espero-1”). In addition, "live" and "dead" water began to be sold in pharmacies and shops in bottled form.

It is believed that these waters help with various diseases. There are many wonderful and entertaining stories about healing with the help of "living" and "dead" water. But they are reported in very dubious books and even more dubious articles. I'm used to sticking to firmly established facts.

I do not pass judgment on activated water, but I want to warn you: be careful with healing waters which have not yet been sufficiently tested in practice. Take them only on the recommendation of a doctor, and not healers, sorcerers and authors of dubious books. Remember that even such harmless water as rainwater can be harmful: it is soft, you can wash your hair in it, but you should not drink it - it does not contain enough salts we need. But it is not excluded that after acid rain, rainwater may contain components that are undesirable for our body.

Wastewater

I want to end this chapter with a discussion of wastewater. They are neither fresh nor salty. They can be divided into two types: the first come from city apartments, from city sewers, the second - from industrial enterprises. In the waters of the first type, there are feces, urine, paper, soap, food residues. All this settles in the water settling tanks, rots on special sites and does not harm either us or nature. In addition, there are elements in wastewater that natural purification processes cannot cope with: surfactants; microbes and viruses; medicines.

We take a lot of drugs, but not all of them are completely absorbed by the body. Residues are excreted through the gastrointestinal tract and kidneys and end up in wastewater as a result. Antibiotics and analgesics, contraceptives, anti-obesity drugs, steroid hormones, etc. etc. It is still difficult to predict the consequences of this type of pollution. Perhaps now it is not yet particularly dangerous for humans. But what can happen after some time, for example, when antibiotics come into contact with pathogenic bacteria? Either antibiotics will be stronger, or antibiotic-resistant strains will arise. The latter promises us big trouble...

Let's not guess, however, and talk about wastewater from enterprises. Of course, we cannot refuse chemical and pulp and paper plants, electroplating shops, metallurgical and machine-building plants, nuclear power plants and everything else that saturates water with heavy metals, harmful chemicals and even radioactive isotopes. But we must have some idea of ​​what, on the one hand, not to indulge in panic, and on the other, to observe the necessary caution. I will list this information point by point.

1. At the moment, tens of thousands of chemical compounds are known to mankind. Once in the water, these substances undergo various changes: they decompose, react with each other, with chlorine or ozone, which disinfect water, and as a result, new modifications previously unknown to science can be obtained. Relatively few of this huge number of compounds have been studied so thoroughly that one can conclude that they are neutral or, conversely, that they have a harmful effect on the human and animal organisms; There are no MPCs for these substances. True, the most dangerous ones are still investigated, and we will talk about them in chapter 3.

2. Do not think that we are fed sewage into the water supply. Wastewater treatment and preparation of water supplied to our apartments are two different processes carried out by the state unitary enterprises Vodokanal, which are found in any city. Wastewater is treated at special aeration stations, where they are filtered, settled, saturated with oxygen and only then enter natural reservoirs, and the sludge (dry matter) is disposed of. There are different ways to dispose of it: bury it in the ground, dump it into the ocean, transport it to the territory of another state, or process it at a special factory. Wastewater purified from dry residue is not chlorinated, at least in our country. The reason is simple: yes, there are many pathogenic bacteria and viruses in this water, but if you kill them with chlorine, then chlorine will enter the reservoirs in a monstrous amount, and this is much worse than bacteria. Nature gets along with them, but not with chlorine and its compounds. Fish, animals and humans are poisoned.

Purified wastewater, of course, contains harmful substances, but after entering vast natural reservoirs, the concentration of these substances is often diluted to negligible values ​​that cannot be detected by the most accurate methods of analysis. I’ll add right away that this does not happen everywhere and not always: for example, in Lake Ladoga and the Neva the situation is relatively favorable, but the Rhine or the Volga is a completely different story.

From natural reservoirs, water is taken for domestic consumption (most importantly for drinking and cooking). This is a completely different operation, not related to wastewater treatment. This is done by the water intake and water treatment stations of Vodokanal. Water goes through the necessary stages of purification, chlorinated or fluorinated, and then enters the water supply network. Dangers are possible: poor-quality cleaning, rusty water pipes, volley unauthorized dumping of industrial waste by some enterprise.

3. However, a person is hardy. Our body is able to cope with toxic substances, if they do not come in too large doses or in small, but constant. If there is fish in the river from which the water is taken, then the situation is not yet deadly, and if beavers have appeared in the reservoir, which are very sensitive to water quality, things are generally fine. Well, if the sturgeons swam belly up, this is already a crime. Will a household filter help? I strongly doubt it.

4. Rivers and lakes have the property of self-cleaning. This is an exceptionally powerful natural mechanism. However, you can't be complacent. Watch your drinking water and, if something goes wrong, sound the alarm!

After two world wars at the bottom Baltic Sea a mass of German weapons, bombs, explosives, cylinders with military agents - mustard gas were flooded. What happens to these "gifts" of the past now, decades later? In the journal "Ecological Chemistry" I got acquainted with the articles of specialists who regularly examine the area of ​​burials. The bodies of containers and bombs rust, the resulting harmful chemical compounds seep into the bottom waters, and most importantly - mustard gas! But it turns out that there are microorganisms that “eat” mustard gas and convert it into compounds that are safe for living organisms. Now, if all the bombs and containers fall apart at once and there is a volley of poison, then these bacteria can die.

However, no one knows what will happen then. We can be sure of only one thing: the millstones of nature turn slowly but surely, and if it is not strained, it will forgive and save us.