Water pollution and protection

Economics in relation to the water resource can be either consumer or user.

Consumer: takes water from a source, uses it for needs of production and returns it but in the other place, less quantity and different quality.

User: doesn’t take water from a source, but uses it as media (shipping, fishing, sport) or source of energy (hydro-power stations). However they change water quality also.

Water pollution is classified as:

Chemical pollution: is caused by harmful non-organic (acids, alkaline, mineral saline) or organic (oil, oil-products, surface active substances, washers, pesticides) substances incoming to water surface layers. Most of non-organic substances are toxic for community inhabiting waters (compounds of arsenic, lead, mercury, copper, cadmium, chromium, fluorine). They are absorbed by plankton and then transmitted through feed links to other organisms. It’s accompanied by cumulative effect that 10 times increases amount of harmful compounds in every next feed link. Metal manufacture, mineral resource industry, chemical industry, agriculture (fertilizers) are the main sources of mineral pollution. Sewages of chemical plants contain great quantity of organic compounds. Most of synthetic washers contain phosphorus. Increased quantity of phosphates in sewages causes intensive growing of blue-green water plants - water “blossom” what lowers oxygen in water and kills water animals.

Physical pollution: changes physical characteristics of water – clarity, contents of suspension and insoluble agents, radioactivity. Power stations emitting thermal waters are sources of thermal pollution (especially Nuclear Power Stations, t = 45 deg C).

Biological pollution: is caused by microorganisms incoming to water through sewages (virus, bacteria, fungus, protist). Biological pollution is examined by the following parameters:

1. “koli-index”: quantity of intestinal bacillus in 1 Liter of water (TLV = 3);

2. biochemical oxygen consumption (BOC): amount of oxygen needed to decompose organic substances into inorganic (BOC TLV = 3 mg/l in potable water within 5 days).

Water protection:

1. recycling;

2. wasteless technologies;

3. burying sewages;

4. purifying water;

5. reducing use of chemicals in agriculture;

6. imroving tankers.