Venice – emergencies

Venice emergency-dead fish

Venice emergency-dead fish

Venice – emergencies
-The Emergency , algae
An exceptional bloom of algae can give a high level of pollution.Started in 1989 ,the removing of 200,000 cubic meters of algae and lasted five years with high costs for disposal and transport .
The maintenance of navigable way of water requires collection of billions of cubic meters of mud . If in the past these were used to fill the “sache” ( depth of the lagoon called Sacks) . Several of pockets existed in the past in the lagoon have been gradually filled in time, thus giving rise to the real artificial islands , for example Sacca Sessola , Sacca Fisola , Sacca San Biagio.
In the  North area of Venice still stands intact , the Sacca della Misericordia , large basin that flows to the island of Murano and is partly used as a nautical port  ) , becomes an environmental problem because of the the destination of the sludge .A protocol (called of the Sludge) provides in addition  the criteria to be used for digging , although the methods of sampling, analysis ( particle size , chemical and physico- chemical microbiological ) and from samples at the end of their characterization is indicated the possible sites for the delivery of the sludge ,in about four categories corresponding to levels of pollution.The “special”ones must be disposed in landfills type “B ” that is outside the perimeter of the lagoon . In addition to the discomfort create to the nautical movement, the excessive accumulation of mud occluded also drains which was opened directly in the canals and completely clogged obstructed their spills, scattering inside the masonry and progressively degrading structures .
 
The port traffic .
Is at the same time one of the main economic resources of Venice , and at the same time one of the constraints to safeguard its lagoon. In addition to the risk of mishandling or failure , large ships ( 289×36 meters) are accused of creating a wave that put in danger the banks and construction.
THE SWELL – caused by engines with time creates real caves and collapses of the sections of walls. The ascent and descent of the waves leads to the wash of the mortars , and capillary rise of salt , and the loss of impermeability , causing extended states of degradation , or even collapses . venice emergency - algae
Subsidence
– phenomenon of lowering of the ground , one of the causes of the increase of high water .Progressive compaction of sediments and partly  tectonic deformations  of the substrate low the ground with 0.4 mm per year, but 4 cm per century.
– The anthropogenic subsidence mainly due to the pumping of water and gas from underground.The systematic use of groundwater through wells began in 800 to provide drinking water to Venice. Exploitation of massive industrial supply in the years 60-70 , when they were drilled deeper and deeper ( 300-400 meters) drawing on several levels and with pumping systems more powerful , did significantly lower the ground level in the years ’40 for the Venice city . The construction of an industrial aqueduct that supplies water from surface, drove the levels up to determine the elastic recovery of the land, following the repressurization of aquifers .
Pollution-
If once the threat from the ground to the lagoon was represented by the flooding of rivers, today primarily is the pollution. The erosion from the sea and pollution are two of the environmental problems of the lagoon, due to the presence of the great industrial center , but also by the rapid development of urbanization , modernization of agriculture and industrialization. The presence of toxic pollutants , dioxin contamination of organic nature , gave events as the mortality of fish ( 1982) , a massive bloom of macro- algae , abnormal coloration of the water channel .
The checks conducted on the chemical plant of Port Marghera, in 1998, find that the lagoon of Venice became one of the four most polluted places from Europe. In the waters of the lagoon of Venice were poured every year 70 tons of dichloroethane, 320 pounds of trichlorethylene, 4 tons of tetrachlorethylene, and 22 tons of bromoform. On air 1500 chimneys unloaded tons of harmful substances and 120 of waste discharge were in the area.
A series of laws and regulations , showed a marked reduction of the pollution in the purification plants
– the reduction of nitrogen waste
– punishments for discharges of the rejection water pollutants in the lagoon
– equipment and modern sewers for urban discharges of Venice.
Emergency tel numbers for the turists in Venice   http://www.about-venice-travel-guide.com/emergency-numbers-in-venice.html
visit my website  http://ginocosta.altervista.org/you-can-do-it.html