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Côtes méditerranéennes menacées :
Risques et défis dans le contexte du changement climatique

Figure 3. Conceptual model of sediment contamination within Favignana Harbour.

4. Conclusion
Dredging within the Favignana Harbour is periodically needed to ensure the safety of
navigation and an adequate depth through time. With the present layout, the entrance to
the harbour is often compromised by the waves and their propagation within the basin,
particularly during Mistral winds. Navigation is limited, especially close to the docks,
due to sand transport under the effect of anticlockwise circulation that reduces the depth
of the seafloor up to the point that sometime during winter part of the sand emerge from
the sea and form a small emerged beach. Handling, treatment and reuse of sediments are
topics that encompasses many disciplines, which are necessary for the successful
implementation of the dredging operations aimed at a beneficial reuse of sedimentary
natural resource. In Favignana, where the Marine Protected Area is almost
uncontaminated, dredging of sediment from the Harbour whit low contamination levels
is necessary to facilitate tourism.
After presentation of preliminary results obtained in the present study, the local
authorities were informed by the moderate exceedances of some contamination
threshold, but showed interest for the following management scenarios:
a) nourishment along the coast; these sediments should be classified with a “light green”

color, due to concentration levels similar to those indicated for quality standard of
marine waters or otherwise some treatment should be adopted;
b) on shore recreational activities like soccer and beach volley fields; these sediments
should be classified with a “dark green” color, due to concentration of contaminants
below threshold indicated for public and private soils and chlorides should be
previously reduced to avoid aquifer salinization.

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