People tend to believe that water from an underground source is definitely much cleaner and purer than surface waters. It is true that the passage of underwater through clay layers for instance allows for a good filtration, yet there are other soil areas that are responsible for what is generally known as sediment pollution. Suspended sediments also have the bad reputation of transporting all sorts of chemicals such as pesticides, toxins and even heavy metals. Special water tests are required to determine the type of suspended sediments and whether they are a threat for animals, plants and people. The sediments will eventually accumulate and deposit at the mouth of the rivers.
The only way to eliminate the risks posed by sediment pollution is to stimulate their coverage with active natural layers of sediments that when thick enough will diminish risks significantly. From this point of view the most exposed are coastal or bay areas that are covered by ice a pretty long time of the year, in such parts of the world the formation of the protective sediment layers needs to be artificially stimulated in order to be efficient in fighting sediment pollution in general. Sand will do very well for the matter contributing to the natural recuperation of the environment.
How does sediment pollution affect underwater life in general? Poor light quality is the first consequence of high sediment concentration in the water: without sun light, water plants cannot develop properly due to the impossibility to make the photosynthesis and they will not provide enough food for the fish. Moreover, studies indicate that suspended sediments increase the water temperature, making the habitat unfriendly for animals and plants alike. And even if the sediment settled, it would still risk the evolution of fish eggs that get suffocated at the bottom of the rivers or lakes.
Sediment pollution often results from erosion, but in its turn it further perpetrates erosion like in an inescapable circle. Fish and plant deaths have often been caused by the too high sediment presence in the water: the fish gills get irritated just like the mucous membranes on their eyes for instance. Fish that become contaminated with heavy metals as a result of sediment pollution can often get caught and eaten by people, thus pushing the contamination level even further. Without special measures to prevent soil corrosion, and with an increased control of residual waters, we will continue to assist to an every day more complex deterioration of our environment.