A pilot project of anthropogenic Venice uplift by deep seawater injection.

Recent modeling studies suggest that injecting seawater into a 600-800 m deep salty aquifer underlying the Venice Lagoon might help raise the city uniformly by 25-30 cm, and possibly up to 40 cm, over a 10 year time. To test the feasibility of an actual programme of anthropogenic Venice uplift a pilot project is designed with the aim at investigating the expected occurrence over a limited area selected on purpose within the lagoon where three boreholes down to 800 m are drilled, and seawater properly treated for geochemical compatibility is continuously injected into the geologic formation of interest during 3 years. Using an improved reconstruction of the geologic formations based on new seismic surveys to be carried out in the lagoon area, the pilot project plans the continuous monitoring and accurate measurement of: 1- fluid pore pressure, 2- expansion of the injected underground units, 3- vertical and horizontal motions of the overlying land surface via spirit levelling, GPS and InSAR. A continuous real-time control of the experiment is envisaged with the aid of site specific much refined hydrologic and geomechanical models properly calibrated over the detailed litho-stratigraphy resulting from the new seismic analyses, ad hoc field tests and the most recently available hydrological and geomechanical data of the Northern Adriatic basin. The present communication addresses a few basic issues concerned with the design of the pilot project and discusses the results expected form the experiment.