Most stored groundwater is ‘fossil’ in its age, having been under the ground for more than ~12 thousand years. Mapping where wells tap fossil aquifers is relevant for water quality and quantity management. Nevertheless, the prevalence of wells that tap fossil aquifers is not known. Here we show that wells that are sufficiently deep to tap fossil aquifers are widespread, though they remain outnumbered by shallower wells in most areas. Moreover, the proportion of newly drilled wells that are deep enough to tap fossil aquifers has increased over recent decades. However, this widespread and increased drilling of wells into fossil aquifers is not necessarily associated with groundwater depletion, emphasizing that the presence of fossil groundwater does not necessarily indicate a non-renewable water supply. Our results highlight the importance of safeguarding fossil groundwater quality and quantity to meet present and future water demands.
Malta’s Water Scarcity Challenges: Past, Present, and Future Mitigation Strategies for Sustainable Water Supplies
The small Mediterranean country of Malta, an island located between Italy and North Africa, has been facing and will continue to face water stress and scarcity in the coming years, receiving the designation as the most water stressed country in Europe. In the past, Malta’s water challenges were centered around water quantity concerns, but in more recent years, the severity of their water stress has been strengthened by the deterioration of the groundwater quality and quantity. Through the over-extraction of their groundwater, saltwater intrusion has steadily occurred into their freshwater aquifer systems, worsening their groundwater quality for both domestic and agricultural purposes. The objective of this paper is to conduct an extensive review on the history of Malta’s water problems and how Malta is working to combat its water scarcity concerns. Additionally, this paper investigates the impact of Malta’s water scarcity on its food and energy security challenges. Our study concludes that while Malta has obstacles to overcome in their pursuit of water security and sustainable development, the future remains hopeful, with several alternatives still available. Some of the alternatives explored in this review include wastewater reuse, increased awareness, use of alternative energy sources, rainwater harvesting, and implementation of nation-wide strategic water policies.
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- Award ID(s):
- 1828942
- PAR ID:
- 10273061
- Date Published:
- Journal Name:
- Sustainability
- Volume:
- 12
- Issue:
- 23
- ISSN:
- 2071-1050
- Page Range / eLocation ID:
- 9835
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/su12239835
