bY M. Civita
INTRODUCTION
Italy as a
whole has adequate groundwater resources which supply the main source of drinking water. However, these groundwater resources are affected by four deterioration processes which strongly influence regional schemes toexploit and protect groundwater within land-use planning: drought,
overpumping, saline water intrusion and pollution.
DROUGHT
Stretching through more than 10 degrees of latitude between the Alps and Africa, the climate of Italy ranges between a semi-arid type (ppt.
450-600mm/a, ave. temp. 18°C) in southern areas, through sub-humid
(500-900mm/a, 15"Cj conditions in the northern perimountain region to humid conditions (800-1550+ mm/a, 13°C or less) in the Alps and the Apennines.
This wide range of climatic types, combined with unfavourable
hydrogeological settings in the southern peninsula and in some regions in the north-central area, cause major problems in providing drinking water supplies.
Moreover, in the three years 1987-1989 there was a serious reduction in autumn-winter precipitation due to persistent blocking anticyclones over the Mediterranean area. This has led to severe problems, not only in the areas already mentioned but indeed in the whole country.
It
was possible to observe how conditions of drought may combine with overpumping and natural and/or human pollution to lower the quality of groundwater in several aquifers on the plains and along the coast.OVERPUHPING DEPLETION AND SALINE WATER INTRUSION
This is a major problem in the PO plain, where the large yielding deep industrial zones.
alluvial aquifers are serious ly depleted in urban and
Great urban centres, such as Milan, Venice-Marghera, Bologna, Modena, Ravenna and their surroundings, obtain their industrial and domestic water supplies frorn an alluvial multi-layered aquifer whose potentiometric surface has been drawn down by hundreds of metres.
Consequences of overpumping are:
to increase and extend pollution processes from intensively used land, where important industries and diffuse chemically based agriculture generate many sources of pollution;
important subsidence phenomena, which severely damage rnonuments and ancient art centres such as Venice and Ravenna, where land subsidence has increased flooding by high tides;
increasing saline water intrusion, as along the Adriatic coast of Romagna, in Apulia karstic aquifers, in the hinterland of Augusta- Syracuse in Sicily, in the hinterland of Iglesias, in Sardinia, etc.
GROUNDWATER POLLUTION
The most serious groundwater pollution problems are found in the PO valley and in the north of the country, as well as locally on coastal plains and along the Apennines. Groundwater pollution has steadily increased due to industrialisation, migration of population to towns from the country and the massive use of chemicals in agriculture. Several disasters involving
drinking water supplies have occurred. Although available data
are incomplete, best estimates suggest some 300,000 uncontrolled waste water discharges, almost 500 toxic industrial plants (60% in north Italy), average 16 Gkg/y of DSW (domestic solid waste), average production of IW (industrial waste) of about 50 Gkgly, of which almost 10 are PNW (poisonous and/or noxious waste). Global Italian treating and dumping facilities can handle less than 15% of these wastes. Agriculture uses about 159 Mkgly of pesticides and more than 1 Gkg/y of nitrogen fertilizers. 'The least accurate data concern production of livestock wastes. In some areas of north Italy (Modena, Reggio Emilia, Mantova), the density of pig farming is the highest in the world and, in some places, exceeds legal limits. The nitrogen input from breeding, in the PO Valley alone, is estimated at 400 Mkgly.
In
1986,
whenItaly
began to implement the EEC directive on drinking water quality (80/778/EEC), serious problems became evident in the north of the98
country as is shown by the following examples.
In the Vercelli area, where land-use comprises intensive specialised chemically based agriculture (mainly rice witn some maize, vegetables and
fruit), systematic research took place into shallow and deep well
pollution. Civita et al. (1989) reported that of 281 wells tested, 90% of shallow wells and 35% of deep wells were polluted by pesticides. In Piedmont (NW Italy), more than 220 of 1209 municipalities had to deal with pollution of groundwater sources due to pesticides. In other regions in the north, a study carried out by the National Health Institute (Funari et al., 1989) stated that over 250 municipalities had their drinking water sources highly polluted with pesticides and over 200 with nitrogen from fertilizers, livestock wastes and domestic liquid effluents. Raised levels of organic pollutants in groundwater such as chlorinated solvents (trichloroethylene,
tetrachloroethylene, methylchloroform etc.) are now common in the
surroundings of great industrial and urban centres of northern and central Italy, particularly Milan and Turin. In Milan and its surroundings, about 50% of groundwater is polluted by chlorinated solvents while in Turin and its surroundings, pollution runs at over 15%. Together with chlorinated solvents in these areas, chromium +6 and a new organic industrially generated pollutant, trichloroethilphosphate (generally called "Tris"), are also encountered.
Widely diffused natural substances in groundwater drinking water sources in Italy are also iron, manganese and fluoride, which sometimes greatly exceed the legal standards. High rates of manganese are detected in several zones of Piedmont, Lombardy, Emilia-Romagna, Marche, Tuscany and in volcanic aquifers near Naples where high fluoride levels also occur. These also occur in some zones of Latium and Piedmont.
LEGAL BASIS OF GROUNDHATER DRINKING RESOURCES PROTECTION IN ITALY
A number of laws and regulations include protection of groundwater quality.
The most important is the 319/1976 act, "Rules of water protection against pollution", together with the "Criteria, methods and regulation for application of art. 2 of the 319/1976 law", brought into force in 1977. It was only in 1985 that a regulation on drinking water quality (DPCM 08.02.1985), based on the 80/738/EEC directive on drinking water standards,
was enforced. But the most powerful act on this specific topic is DPR 386/1988 which meets the requirements of EEC directive 80/778. This introduces as national standards guide and allowable limits and introduces water protection areas and related framework statements for control and policy.
The act also provides for full technical regulation. In late 1988 the Ministry for the Environment set up a commission of experts to undertake this task. The terms of reference cover;
General principles;
Protection areas for wells, springs and surface water sources;
Hydrogeological surveys and reports;
Land-use regulation and human activity control;
Protection areas for drinking water sources;
Vulnerability maps;
Analysis and central organisation;
Disaster plans.
The work is almost complete and soon this technical regulation will be part of Italian law.
REFERENCES
Civita, M., Fisso, G., Governa, M.E. and Rossanigo, P., 1989. Prima
valutazione dell'impatto dei diserbanti sugli acquiferi de1
Vercellese. Acque Sotterranee, 6, 21.
Funari, E., Donati, L., Donati, G., Cavallo, S., Paloletti, L. and Donelli, G ., 1989. L'amianto nelle acque destinate al consumo umano. Acqua e Aria, 9.
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