GIS: a Powerful Tool for the Description of Seawater Quality in Proximity of WWTP Sea Outfalls

Claudia Lasagna (1), Franca Palumbo (1), Patrizia Rosi (1), Maurizio Costa (2), Debora Verardi (2)

(1) A.M.G.A. S.p.A., Genoa (IT)
(2) R.S.T.A. s.c.r.l., Genoa (IT)

The law concerning surface water protection in Italy has recently changed, precisely with the issue of D. Lgs. 152 in May 1999. As far as seawater protection and monitoring are concerned, major tasks have been committed to local ARPA's, that is to the agencies dealing with environmental protection in general. Frequent monitoring must be carried out on water, sediments, bio-indicators such as mussels. Nevertheless wastewater treatment plant managers haven't been charged with any specific task related to the quality control of seawater affected by the discharge of effluents from WWTP's. This has not stopped Genova Acque, the company that manages eight WWTP's within the city of Genoa, from monitoring seawater quality. The RSTA company has been involved in in situ measurements and sample collection from GIS-referenced sites, while the laboratory of the AMGA company has carried out off-line analyses. The data obtained have been used for drawing theme maps which allow a very quick evaluation of seawater quality in any zone.