This document discusses water pollution and ways to prevent it. It is divided into several sections that describe the causes and types of water pollution, how the degree of pollution is determined, and recommendations for preventing water pollution. The types of pollutants include natural sources like salinity and iron compounds as well as artificial sources such as wastewater, agricultural runoff, and landfills. The document recommends measures like installing meters, limiting fertilizers, building sewage treatment plants, and using environmentally-friendly cleaners to reduce water pollution.

1. GROUP 3
Julia Brzozowska – Poland
Anna Hermanowska – Poland
Agata Panasiuk - Poland
Hiurma Martín Cejas - Spain
Alejandro Martínez González - Spain
Marta Peña Díaz - Spain
Pablo Rodríguez Hernández - Spain
Jorge Victorian Gago - Spain
Paula Acha Evora - Spain
Alejandro Acosta león - Spain
Kaan - Germany

2. Water pollution - disadvantageous changes of chemical, bacteriological and physical properties
of water caused by the implementation of inorganic, organic, radioactive substances, or heat in
excess which limit or make the usage of water for drinking and economic purposes impossible.

3. Water pollution is caused mainly by the chemical
substances, bacteria and other microorganisms which
are present in natural water in the increased amount.
The chemical composition of pollutants is being shaped
with natural factors, e.g. dissolution of the substances
present in the soil and rocks, the development and dying
of aquatic organisms, and anthropogenic factors as well.

4. Division of pollutants:
By the origin:
Natural: salinity, iron compounds
Artificial: wastewater, agricultural wastewater, water originating in the rubbish dumps
By a degree of the harmfulness:
direct harm: gasworks, coke plants, factories of artificial fertilizers, pulp mills, factories of synthetic fibres
indirect harm: the pollutants that lead to the curtailment of oxygen in the water below the level essential to keep aquatic
organisms alive.
According to the criteria of the permanence of pollutants:
point sources - wastewater drained in the organized way with plumbing
surface or area pollutants - pollutants rinsed with precipitations
pollutants from linear or zone sources - pollutants produced by the means of transport

5. Degree of water pollution
The degree of waters pollution is determined with so-called gauges of pollution which
shows the amount of the substance in milligrams per 1 cubic dm of water. A
concentration of dissolved oxygen which can reach the maximum level of 8,9 mg/dm is
one of the most important indicators of surface water pollution - lower level of the oxygen
concentration proves that water is polluted with organic compounds that are
biodegradable; the decrease in the oxygen level below 4 ³ mg/dm causes many aquatic
organisms die. The other indicators of natural water pollution is a biochemical oxygen
demand which is a measure of the biochemical biodegradation of the organic compounds;
a chemical demand of the oxygen - the measure of the content of all organic compounds;a
presence of
a mineral and organic suspensions as well as inorganic
and organic compounds of nitrogen and phosphorus.

6. How to prevent water pollution:
- putting meters on;
- limiting artificial fertilizers which penetrate groundwater;
- building the sewage farms;
- installing filters in factories which waste is drained out with
running water
- not pouring cleansers (like soap, shampoo, washing powder,
abrasives) to water
- use bio of environmentally friendly detergents
- taking care of the purity of water (not throwing cans and
rubbish into water)