Challenges and Opportunities for Sustainable Management of Water Resources in the Island of Crete, Greece

Abstract

Crete, located in the South Mediterranean Sea, is characterized by long coastal areas, varied terrain relief and geology, and great spatial and inter-annual variations in precipitation. Under average meteorological conditions, the island is water-sufficient (969 mm precipitation; theoretical water potential 3284 hm3; and total water use 610 hm3). Agriculture is by far the greatest user of water (78% of total water use), followed by domestic use (21%). Despite the high average water availability, water scarcity events commonly occur, particularly in the eastern-south part of the island, driven by local climatic conditions and seasonal or geographical mismatches between water availability and demand. Other critical issues in water management include the over-exploitation of groundwater, accounting for 93% of the water used in agriculture; low water use efficiencies in the farms; limited use of non-conventional water sources (effluent reuse); lack of modern frameworks of control and monitoring; and inadequate cooperation among stakeholders. These deficiencies impact adversely water use efficiency, deteriorate quality of water resources, increase competition for water and water pricing, and impair agriculture and environment. Moreover, the water-limited areas may display low adaptation potential to climate variability and face increased risks for the human-managed and natural ecosystems. The development of appropriate water governance frameworks that promote the development of integrated water management plans and allow concurrently flexibility to account for local differentiations in social-economic favors is urgently needed to achieve efficient water management and to improve the adaptation to the changing climatic conditions. Specific corrective actions may include use of alternative water sources (e.g., treated effluent and brackish water), implementation of efficient water use practices, re-formation of pricing policy, efficient control and monitoring, and investment in research and innovation to support the above actions. It is necessary to strengthen the links across stakeholders (e.g., farmers, enterprises, corporations, institutes, universities, agencies, and public authorities), along with an effective and updated governance framework to address the critical issues in water management, facilitate knowledge transfer, and promote the efficient use of non-conventional water resources.

Water Conflicts: From Ancient to Modern Times and in the Future

“…The reuse of reclaimed wastewater, generated by wastewater treatment plants (WWTPs) and food industries, particularly in agricultural production [102][103][104], seems ideal for water-scarce problem areas (e.g., Mediterranean basin), promising to reduce user competition for water and relieve pressure on water resources. Developments in (cost) effective, and environmentally and climate-friendly treatment technology is a critical factor in favor of increasing water reuse in these areas [89,91], but they need further political and economic support to address regulatory issues and social-economic constraints [100][101][102][103][104][105][106]. An excellent example of this is the legislative initiatives and reuse guidelines proposed by the European Union (EU) [103], which have been adopted in conjunction with other relevant EU policies (e.g., the introduction to the circular economy concept and adaptation to climate change) [103].…”

“…However, there are still issues for the environmental footprint of this practice, particularly in developing countries [128,132]. Optimization of the technology, focusing on small-scale desalination plants, combined use of the sea and brackish water, and energy recovery, are of concern for the near future [106,132]. The other issue is the high cost of desalinated water, which has to be incorporated in water tariffs, leading to an increased water price compared to the regular water.…”

Water Supply and Water Scarcity

“…The Mediterranean region is among the regions that will be affected by climate fluctuations. Tzanakakis et al [17] reviewed the availability of water resources and water uses in the island of Crete, highlighting the current and future challenges and opportunities for water management. In the island, despite the high theoretical water potential, there are areas under water scarcity, particularly in the southeastern part of the island, related to local soil-climatic conditions and the imbalances between water availability and demand.…”

“…Important challenges highlighted by the study are the over-exploitation of groundwater, over-consumption mainly in the agricultural sector, mismanagement at the local level, low overall water use efficiencies, limited use of non-conventional water sources, lack of modern mechanisms of control and monitoring, and inadequate cooperation among stakeholders. The study proposes the improvement of the current water governance framework encouraging the implementation of an integrated and flexible water management plan, accounting for local social and economic specificities to allow for the successful adaptation to changing climatic conditions and to increasing water needs [17]. Moreover, it proposes the exploitation of alternative water sources (recycled water and brackish water); however, further work should be done on legislative framework to promote water reuse, particularly in agriculture, while ensuring the product safety and marketability.…”

Combining Geostatistics and Remote Sensing Data to Improve Spatiotemporal Analysis of Precipitation

“…This research work focuses on the Greek island of Crete, which is located in the southeastern part of the Mediterranean Sea. Crete was selected as a study area due to the availability of precipitation data and because, according to recent studies, it is a hot spot for the effects of climate change [ 21 , 22 ]. Rainfall variability in Crete was also found to be linked to NAOI variability.…”