Hydric Restoration of the Agua Amarga Salt Marsh (SE Spain) Affected by Abstraction from the Underlying Coastal Aquifer

The Agua Amarga coastal aquifer, located in the southeast of Spain (Alicante province) has suffered a significant decrease in its piezometric levels due to its use to supply water to Alicante I and II desalination plants. In order to recover its natural levels and to preserve the salt marsh of ecological interest linked to the aquifer, whose origin is related to ancient saltworks, a pilot scheme based on depositing seawater over the salt marsh surface has been carried out from December 2009 to July 2010. As a result, piezometric levels have increased by around 2 and 3 m below the salt marsh and a general decrease in groundwater salinity of between 15 and 100 g/l has been measured. A flow-transport numerical model with SEAWAT is used to assess and evaluate the seawater depositing programme.