Abstract
In this study, we estimate baseline conditions in terms of the current risk of well salinization on the Baltic Sea island of Öland, Sweden, and assess the effects of future sea level rise on the land area, infrastructure and cultural values. We use a multicriterion geographical information systems (GIS) approach. Geomorphological and physical parameters affect the risk of saltwater intrusion into freshwater aquifers, including their hydrology, geomorphology, and climatology; the spatial distribution of the current risk of salinization is mapped in this study. In the event of a future 2 m sea level rise, a total land area of 67 km2 will be inundated on Öland, corresponding to approximately 5% of the island’s land surface. Inundation includes urban areas, nature reserves, and animal protection areas, implying the loss of environmental and socioeconomic values. A future 2 m sea level rise will also cause direct inundation of 3% of all wells on the island. Currently, 17.5% of all wells are at a high risk of becoming saltwater contaminated. More generally, the present results add evidence showing a relatively high vulnerability of major Baltic Sea islands and their infrastructure to future sea level rise. The approach used here and related results, including salinization risk maps, may prove useful for decision-makers in the planning of infrastructure. Drilling of new wells could for instance preferably be done in areas with identified lower risk-index values, which would facilitate an overall higher freshwater withdrawal in the interest of the entire island.
Highlights
Even without the present results show that the risk of saltwater intrusion into freshwater is already high on sea levelÖland, rise, the present results show that the[3,27], risk of intrusion freshwater aquifers is as in many other parts of the world as saltwater the groundwater tableinto is shallow in low-lying already highareas
In a longer time perspective, the regional economy could suffer from a decrease of tourism as a result of the loss of land
With a future sea level rise of 2 m, 5% (67 km2 ) of the land area of Öland will be inundated, along with 3% of all of the island’s wells, including wells used in summer houses, smaller farms, and as energy wells
Summary
Saltwater intrusion frequently occurs naturally as heavier saline waters tend to partly displace freshwaters in coastal areas [2]. This intrusion and the associated salinization risk can be greatly aggravated by water extraction in coastal wells that provide the society with freshwater, irrigation water or water for industries [3]. This may result in the wells becoming unusable as a source of freshwater.
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call