THE QUALITY OF WATER IN OUR STREAM CROSTOLO

As you can see from the map, the stream Crostolo runs through a large portion of the province of Reggio Emilia . On the map you can see the locations of the places where samples of water have been taken for analysis, as shown in the keys below.

C1: La Bettola-Vezzano (not far from the spring)
C2: rio Campola-Vezzano sul Crostolo
C3: Roncocesi-Reggio Emilia (close to industrial and big urban area)
C4: Begarola-Cadelbosco di Sopra
C5: Ponte della Bastiglia-Cadelbosco di Sopra
C6: S.Vittoria-Gualtieri
C7: Ponte Baccanello –Guastalla (close to the mouth of the stream into the big river Po )

It is a typical torrent stream, as we can see from the following flow diagram registered in Guastalla in the year 2004.

POLLUTION OF SURFACE WATER

All water, whether surface or underground, is able to react to the point or non-point letting of pollutants. This ability for self-depuration includes a lot of physical, chemical and biological activities in order to bring the ware back to its original state. If the amount of pollutants exceeds the water capacity of self-depuration, then it evidences phenomenons such as eutrophication and chemical/biological contamination.
Eutrophication consists of excessive growth of algae in favourable conditions, especially during the summer. A high quantity of nutrients like phosphates and nitrates allows the proliferation of algae. Their consequent degradation and rotting determines a total consumption of dissolved oxygen in water. Therefore micro-organisms which can survive without oxygen proliferate and they produce ill-smelling and toxic substances (ammonium).
Chemical contamination is mainly caused by domestic and industrial waste water, and fertilizers used in faming.
Microbiological contamination is due to domestic and livestock sewage, when not depurated. They may contain millions of micro-organisms/ml, and they can be highly pathogen for man (hepatitis, typhoid, salmonellas, vibrio cholera). If this waste water gets into waterways without proper depuration, it can cause serious pollution and epidemic risks.