1. The Po
The Po, the most important Italian river for length and course constitutes, together with its numerous tributaries, the only real river system of the peninsula. The ecosystem of the Great River is fundamental for the entire northern Italy. The Po furnishes water for urban, industrial and agricultural use. Its power is exploited for producing electric energy.

2. Its waters are being constantly degraded by the unloadings of the cities that don't possess a depuratore; from the industries that release polluted black water and finally, from agriculture that employs an excessive quantity of herbicides, chemical fertilizers and it also unloads sewages coming from animal breedings.

3. The river doesn't have the ability of biodegrading everything and the Great River is slowly decaying. Yet, the Po should be and could still be an environmental, cultural and tourist attraction.

4. Water is an essential element to life.

5. It represents 2 / 3 the weight of man and even the 9 / 10 the weight of a plant. The degree of pollution is established by measuring the biochemical oxygen demand (D.B.O.). The D.B.O. is used to measure the weight of dissolved oxygen in the biological process of degradation of organic materials. If the concentration of pollutants increases significantly, its degradation depletes the oxygen dissolved in water and can produce suffocation of a large number of aquatic animals.

6. Origin and nature of pollutants
Water pollution is mostly due to uncontrolled releases:
1. urban waste water

7. 2. industrial waste-water

8. 3. agricultural pollution

9. If the pollutant concentration is too high, life disappears and the rivers and lakes are transformed into open sewers. The increase in water temperature, which leads to a decrease in oxygen, can seriously threaten aquatic life. The continuous increase of water used in industry increases this danger.

10. THANK YOU FOR YOUR ATTENTION