Commissioned: Consorzio Venezia Nuova – Magistrato alle Acque Venezia
Period: 2005 - 2008
Country: Italia
In recent years, sediment management in the Venice Lagoon, which represents a unique and complex area, has been a key issue in maintaining the ecosystem’s characteristics. In 2005, drawing on knowledge obtained through 15 years of research on the lagoon environment and the experience gained in recovering morphological structures, the Venice Water Authority promoted the project SIOSED – the experimental determination of the effects of reutilizing the most diffuse lagoon sediments. The project was realized through the agent Consorzio Venezia Nuova and coordinated by Thetis in collaboration with SCRIPPS Institution of Oceanography (SIO) in La Jolla, California, USA, the National Research Council’s Institute of Marine Science in Venice, the National Institute of Oceanography and Experimental Geophysics in Trieste and the company SELC in Venice.The project was designed to determine whether the lagoon sediments could be reutilized in morphological reconstruction work in the Venice Lagoon. The primary objective of the project was to formulate lagoon sediment management strategies using the most current scientific approaches and methods available, which were of an integrated and multidisciplinary nature, for the overall improvement of the Venice Lagoon Ecosystem; this followed the guidelines of the Special Law and the direction indicated in the 1993 Protocol of Agreement, and was in compliance with the Directives and European Policies. The result of the project was an accurate, authoritative, and scientifically-sound environmental risk assessment for disturbing lagoon sediments, currently classified as type A (low level of contamination according to the 1993 Protocol of Agreement). The study provided for the construction of an experimental testing ground consisting of submerged banks of type A dredged sediments. The evolutionary processes of these structures and the effects on the surrounding areas were monitored for approximately two years, evaluating the geochemical, biological (from microbe communities to macroinvertebrates), ecological and toxicological aspects in an integrated manner.
The results obtained produced a broad range of data on the effects of disturbing and reutilizing the sediments and information relating to the lagoon ecosystem’s processes; the information obtained will serve as a point of reference for future studies and for sustainable ecological management of the sediments in the Venice Lagoon. Focus was placed on obtaining, from all the evidence gathered, concise responses to interpretive and management problems relating to the contamination of the lagoon sediments.
