Kouli_etal_2008_Groundwater modelling_BOOK.pdf - Pantelis ...

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Beatrice M.S. Giambastiani, Pauline N. Mollema and Marco Antonellini
As the modeling simulations show, the future sea level rise will accelerate the increase in
salt load and seepage affecting the entire unconfined coastal aquifer with a very shallow and
inland brackish-freshwater interface. As the soil becomes more saline, farmland degradation
and vegetation growth problems would also occur.
An integrated management in our study area needs to consider:
• Lack of water during the year compared with the variable demand during the seasons
for tourism, agriculture and industry;
• Management of drainage and irrigation in the farmland area;
• Freshwater-saltwater interface management to preserve freshwater wetlands
ecosystem and to avoid soil salinization;
• Coastal dune conservation and restoration;
• Interactions between groundwater and surface resources traditionally treated as
separated resources;
• Sustainability of the different water management strategies in the local economy;
• Role of each stakeholder within the EU and local regulations framework.
Remediation and preventative actions should be taken in time and planned on a long time
basis and large space scale. Integrated coastal management should consider the aquifer, coast
and dunes as a single and complete system and should take into account the possible feedback
effects of each action. Generally, short term strategies are often adopted to solve emergency
situations but long term strategies require a complete knowledge of the physical and
ecological process so as to be flexible enough to adapt to the changing climate scenarios
(Antonellini et al., 2008). In addition, the interactions between surface and ground waters as a
connected resource need to be more explored in order to find innovative strategies to protect
the coastal aquifer and avoid their current management as separate resources. This behavior
typically results in the separate estimation of the sustainable yield of surface and groundwater
systems when, in fact, their yields are interdependent (IAH, 2004). In fact surface-ground
interaction can have significant implications for both water quantity and quality; water flow
regimes, water security, aquatic ecology, salinity and nutrient loading can all be affected by
the flow of water between surface water and underlying aquifer, especially where this last one
is polluted by saltwater. In this case, there needs to be improved modeling of surface and
ground waters interconnectivity, increase density of monitoring boreholes and rainfall
gauging stations in order to improve data collection.
Further investigations can be applied and other issues need to be considered in our study
area in order to advance the scientific understanding of the aquifer and help policy makers to
implement more effective management of the scarce freshwater resources in the area:
• Water quality monitoring of irrigation canals;
• Groundwater monitoring network;
• Geophysical surveying for mapping the recharge and discharge zones along the
rivers as well as for mapping the brackish-freshwater interface in the unconfined
aquifer;
• Combining surface and ground water modeling with groundwater chemistry to better
understand the migration of saline groundwater toward freshwater zones;