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Article

Swimming Pools in Water Scarce Regions: A Real or Exaggerated Water Problem? Case Studies from Southern Greece

by
G.-Fivos Sargentis
1,*,
Emma Palamarczuk
2 and
Theano Iliopoulou
1
1
Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 157 72 Zographou, Greece
2
INP Ensiacet, University of Toulouse, 31030 Toulouse, France
*
Author to whom correspondence should be addressed.
Water 2025, 17(20), 2934; https://doi.org/10.3390/w17202934 (registering DOI)
Submission received: 8 September 2025 / Revised: 3 October 2025 / Accepted: 8 October 2025 / Published: 11 October 2025
(This article belongs to the Special Issue Challenges and Innovations in Resilience of the Water-Energy-Food Nexus)
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Abstract

Swimming pools, symbols of luxury in tourism-driven Greece, raise concerns about water consumption in water-scarce regions. This study assesses their hydrological impact in two regions of Southern Greece, West Mani (Peloponnese) and Naxos Island (Cyclades), within the water–energy–food nexus framework, evaluating the resulting trade-offs. Using satellite imagery, we identified 354 pools in West Mani (11,738 m2) and 556 in Naxos (26,825 m2). Two operational scenarios were evaluated: complete seasonal emptying and refilling (Scenario 1) and one-third annual water renewal (Scenario 2). Annual water use ranged from 39,000 to 51,000 m3 in West Mani and 98,000 to 124,000 m3 in Naxos—equivalent to the needs of 625–2769 and 1549–6790 people in West Mani and Naxos, respectively. In Naxos, this volume could alternatively irrigate 27–40 hectares of potatoes, producing food for 700–1500 people. Energy requirements, particularly where desalination is used, further increase the burden, with Naxos pools requiring 384–846 MWh annually. Although swimming pools are highly visible water consumers, their overall contribution to water scarcity is modest compared to household and agricultural uses. Their visibility, however, amplifies public concern. Rainwater harvesting, requiring collection areas 10–24 times larger than pool surface areas, especially in residential and hotel settings, could make pools largely self-sufficient. Integrating such measures into water management and tourism policy can help balance luxury amenities with resource conservation in water-scarce Mediterranean regions.

1. Introduction

Water scarcity is an escalating global challenge, particularly in arid and semi-arid regions where freshwater resources are under increasing pressure from population growth and economic activities [1,2]. In Mediterranean countries like Greece, where tourism constitutes a significant economic driver [3,4,5], the proliferation of swimming pools in hotels, resorts, and private residences has raised concerns about their environmental footprint [6,7]. Swimming pools, often seen as symbols of leisure and luxury [8], require substantial water for filling, maintenance, and compensation for losses due to evaporation, cleaning, and splash-out [9,10]. In water-scarce regions, this demand can exacerbate local water stress [11], potentially competing with essential needs such as agriculture, domestic use, and ecosystem preservation in the context of the water–energy–food nexus [12,13]. However, the extent to which swimming pools contribute to water scarcity in Greece—whether they represent a significant problem or a manageable one within the broader water management framework—remains underexplored [14].
Global water consumption patterns as reported by international organizations indicate that agriculture accounts for approximately 70–72% of freshwater withdrawals, industries for 16%, and municipalities (including domestic uses) for 12% [15,16], leaving recreational uses like swimming pools as a minor fraction—estimated at 0.75–1% of the total domestic water consumption [17]. These figures underscore that while pools are visible, their impact is negligible compared to dominant sectors, supporting the need for targeted rather than blanket restrictions in water-scarce regions.
This study investigates the impact of swimming pools on water resources in Greece, a country characterized by its Mediterranean climate, seasonal water deficits, and heavy reliance on tourism. By examining water consumption patterns, evaporation rates, and management practices associated with swimming pools in key tourist regions, this study seeks to quantify their contribution to local water stress.
Acknowledging the complex interrelationships of the WEF nexus, particularly in a geopolitically turbulent environment [18,19,20,21] where self-sufficiency and resilience become essential [22,23,24], swimming pools have also been examined in terms of their implications on agricultural and energy uses [25].
Although water is recognized as a valuable resource, actual consumption is difficult to perceive, as much of it is discharged indirectly through sewage (e.g., showers and toilet flushes). By contrast, swimming pool water use is highly visible and therefore attracts strong public criticism. This study investigates whether the environmental burden attributed to swimming pools is supported by data or amplified by perception [26]. We compare their water consumption with that of individuals and agriculture, framing the issue as a real or perceived problem.
We employ a case study approach in two touristic areas of water-scarce Southern Greece, West Mani in the Southern Peloponnese region of mainland Greece and Naxos Island in the Aegean Sea (Figure 1). Using municipal records, private pool data, and detailed satellite image inspections to identify and confirm pool numbers and surface areas, we estimate pool water use and compare it with the water consumption of visitors, residents, and a representative agricultural crop in Naxos. The analysis further explores technological, policy, and behavioral interventions for reducing water demand, with the aim of informing sustainable tourism practices and water management strategies and contributing to a balanced debate on the role of swimming pools in water-scarce environments.

2. Materials and Methods

2.1. Study Areas

The analysis focuses on two representative tourist regions of Southern Greece: West Mani (Peloponnese) and Naxos Island (Cyclades) (Figure 1). Both regions are characterized by a Mediterranean climate with pronounced dry summers and increasing pressure on freshwater resources. Tourism is a major economic activity, and swimming pools, although not a part of local households, have been widely constructed in hotels, resorts, and private villas as amenities marketed to visitors. In Greece, the regulatory framework for swimming pools is neither clear nor unified, yet their construction in tourist destinations—which already offer exceptional seas, unique residences, and landscapes of outstanding natural beauty—is primarily aimed at enhancing the luxury appeal of tourism products rather than serving local residents (Figure 2).

2.2. Identification of Swimming Pools

Due to the absence of centralized registries or reliable official data on swimming pools in Greece, we conducted a detailed remote sensing survey using high-resolution satellite imagery from Google Earth. Pools were manually identified across both study areas and digitized into a geospatial database, including their surface area, as shown in Figure 2. This approach allowed us to account for both completed pools and those under construction.
Because pool depth information is not publicly available, we applied standardized assumptions based on Greek construction practices and regulatory requirements. In Greece, pools up to 1.5 m in depth are subject to a simpler permitting process, whereas deeper pools (>1.5 m) require more complex approvals. Therefore, we conservatively assumed:
  • Pools with a surface area <50 m2 → average depth = 1.5 m
  • Pools with a surface area ≥50 m2 → average depth = 2.0 m
These assumptions allowed us to estimate pool volumes for both regions.

2.3. Water Balance Analysis

To estimate annual water demand, two operational scenarios were considered:
  • Scenario 1 (seasonal emptying/refilling): pools are emptied at the end of each tourist season (October) and refilled before the following season (April).
  • Scenario 2 (partial renewal): pools remain filled year-round, with approximately one-third of the volume replaced annually, in line with standard maintenance guidelines.
Water consumption under both scenarios was calculated by accounting for the following components:
  • Pools in tourist areas typically operate during the tourist season (May to October). Although the guidelines state that changing one-third of the water annually is sufficient for maintenance; a common practice is to empty the pools at the end of the tourist season (every autumn) and refill them at its beginning (every spring).
  • In general, approximately 10% losses are expected from leaks and splashes.
  • Backwash from sand filters is a significant consumer of water which is dependent on the volume of the pool, and it is estimated as well in the calculations.
  • Finally, the evaporation losses during the summer season are important and are taken into account using local meteorological data.

2.4. Water–Energy–Food (WEF) Nexus Analysis

To contextualize swimming pool water use within broader regional demands under the water–energy–food nexus of the area, the following reference values were adopted:
(a)
Domestic water use in Greece: The average Greek consumes 63 m3 water per year (which corresponds to 173 L/day) [29,30].
(b)
Minimum water needs: These are estimated at 18.5 m3 per year (which corresponds to 50 L/day) [31].
(c)
Agricultural water use: Average irrigation needs per hectare are 6000 m3/ha/year [32]. The typical irrigation needs for cultivation of potatoes in Naxos are slightly different, which will be presented in detail in the related section of analysis.
These values allowed for comparison of swimming pool water and energy consumption to domestic and agricultural water and energy consumption benchmarks, as well as the estimation of equivalent food or energy production trade-offs.

3. Results

3.1. Satellite-Derived Estimation of the Pools’ Surface Areas

Since there were no available data on the surface areas and the volumes of swimming pools in Mani and Naxos, a detailed survey was conducted using Google Earth in both regions in order to estimate the surface area of each pool (Figure 3). In Mani, 354 pools were identified, while in Naxos, 499 pools were identified, with an additional 57 pools under construction (Figure 4). Figure 4 also shows the area of each pool.
While satellite imagery from Google Earth provides high-resolution data for pool identification, its accuracy is influenced by image quality, temporal variations, and manual digitization. Studies on similar applications report detection accuracies ranging from 85 to 95%, depending on resolution and algorithmic enhancements [33,34]. It has been estimated that although the grid of the Google Earth digital elevation model is often 30 × 30 m, the horizontal information provided corresponds to a 1:100 scale map [35,36,37,38,39]. In this research, all the pools were located manually with the maximum available detail, and no algorithmic tools were used. Although potential errors may have arisen from shadows or digitization, they can be detected and corrected, if necessary, in the Supplementary Materials, where this study’s .kmz file is provided. In this study, we estimate an overall accuracy of more than 95% based on cross-verification with visible pool features (e.g., blue coloration and rectangular shapes).
Since the actual depths of the pools are unknown, we relied on common construction practices in Greece. Small pools (≤1.5 m depth) are easier to permit, while deeper pools (>1.5 m) require a more complex approval process [40]. Thus, with conservative estimates, we considered the average depth of pools smaller than 50 m2 to be equal to 1.5 m and, for pools larger than 50 m2 to be equal to 2 m.
The surface area of the pools in West Mani was calculated as 11,738 m2 and the volume of the pools was estimated as 19,413 m3. The surface area of the pools in Naxos was calculated as 24,703 m2 and the volume of the pools was estimated as 44,470 m3. The surface area of the pools under construction in Naxos was calculated as 2123 m2 and the volume of the pools under construction was estimated as 3637 m3.

3.2. Estimation of Water Needs for the Pools

In our analysis, we evaluate two water use scenarios for swimming pools:
  • Scenario 1: Pools are emptied at the end of each tourist season (approximately October) and refilled at the beginning of the next season (around April).
  • Scenario 2: Pools remain operational year-round, with one-third of the water renewed at the end of the summer season, in accordance with standard guidelines.
Water consumption was estimated based on the following components:
  • Refilling requirements;
  • Water losses due to filter cleaning;
  • Leaks and splashing, assumed at approximately 10% per month;
  • Evaporation, calculated using climatic data for each area [41] via the Penman–Monteith equation [42].
Rainwater was also considered as a supplementary water source during pool operation.
For West Mani, the consumption profiles under both scenarios are presented in Figure 5a,b. The total estimated consumption is 50,551 m3 for Scenario 1 and 39,446 m3 for Scenario 2 (Table 1).
Similarly, for the island of Naxos, the water consumption profiles for all swimming pools (both existing and under construction) under Scenario 1 and Scenario 2 are shown in Figure 6a,b, respectively. The total annual water consumption is estimated at 123,931 m3 for Scenario 1 and 97,812 m3 for Scenario 2 (Table 1).
The scenario calculations indicate that, because both areas share similar climatological regimes in terms of evaporation and rainfall, the standardized water use per square meter of pool surface differed only slightly between the two regions within the same scenario (Table 2).
Under Scenario 1, the annual volume of water used for swimming pools is equivalent to the annual water consumption of approximately 800–2769 people in West Mani and 1962–6790 people in Naxos. Under Scenario 2, this corresponds to the annual water consumption of approximately 625–2164 people in West Mani and 1549–5359 people in Naxos. The results are summarized in Table 1 and standardized results for 1 m2 of swimming pool are summarized in Table 2. When standardized per square meter, pool water use differs only slightly between regions (<5%), while variation across depth assumptions and management scenarios reaches up to ~70%.

3.3. Assessing Swimming Pools in the Water–Energy–Food Nexus

Swimming pools consume a lot of energy for water circulation, maintenance, cleaning, and overall operation of their mechanical systems. If we also consider that the required water is sourced from desalination, it becomes energy-intensive.
To better understand the scale of this consumption, we compare it to the annual energy consumption of a single resident of Greece which has been estimated to be 6000 kWh/year. The results are summarized in Table 3 for West Mani and Table 4 for Naxos, and standardized results for 1 m2 of swimming pool are summarized in Table 5 for West Mani and Table 6 for Naxos.
Scenario 2 consumes approximately 9% more energy than Scenario 1 in Mani and Naxos. This additional energy use is primarily due to the continuous operation of circulation pumps during the winter months, while Scenario 1 relies more on desalinated water, increasing energy for water production but reducing electricity use in the off-season.
In terms of agricultural water use, West Mani’s cultivation is generally non-irrigated. However, on the island of Naxos, the iconic Naxos potato requires irrigation. The energy content of food provides a useful index for assessing agricultural production. The average adult human requires approximately 1800–3000 kcal/day or 7.53–12.5 MJ/day [43].
For the potato-equivalent assessment in Naxos, the following steps were undertaken to correlate agricultural production with the water volumes used in swimming pools:
(1)
Irrigation requirements were estimated from local evapotranspiration data and crop coefficients, yielding values of 3000–4500 m3/ha/year [44,45,46];
(2)
Crop yield productivity was derived from regional agricultural data, at 25–45 t/ha) [47,48];
(3)
Water productivity was then expressed as potato yield per unit of irrigation water, corresponding to 0.3–0.45 L/kg;
(4)
Food energy equivalents were calculated using an average energy content of 770 kcal/kg potatoes (≈3.22 MJ/kg);
(5)
Food security implications were expressed as the number of people whose annual dietary energy requirements could be met with the equivalent volume of potatoes.
Table 7 and Table 8 present water consumption for all cases, correlated with the corresponding potato yield that would be obtained if the respective water amounts were used, expressed in both total and standardized values (1 m2 swimming pool). The calculations assume pool depths of 1.5 m (Table 7) and 2 m (Table 8).

3.4. Rainwater Harvesting as an Alternative Pool Water Source

The role of each infrastructure type and the strategies for ensuring resilience vary from place to place. To better illustrate the issue of swimming pools, we estimate the water consumption per m2 of pool surface area.
If we assume Scenario 2, that each pool is emptied by only one-third per year according to specifications, this water could potentially be sourced from rainwater harvesting, with collection surfaces varying according to local precipitation patterns, as follows:
  • In Mani, a rainwater harvesting area should be 1066% of the area of the pool if the pool is 1.5 m deep, and 1455% of the area of the pool if the pool is 2 m deep.
  • In Naxos, a rainwater harvesting area should be 1845% of the area of the pool if the pool is 1.5 m deep, and 2389% of the area of the pool if the pool is 2 m deep.
Figure 7 summarizes the average values emerging for the role of water and water harvesting in WEF and swimming pools for the island of Naxos.

4. Discussion

This study provides the first systematic quantification of swimming pool water use in two water-scarce regions of Greece, situating the results within the broader water–energy–food nexus. The analysis shows that while swimming pools represent a visible and symbolically charged use of water, their contribution to overall scarcity is modest when compared to domestic and agricultural demands. For example, the estimated annual consumption of pools in Naxos (98,000–124,000 m3) corresponds to the water needs of 1500–6800 people, while in West Mani (39,000–51,000 m3), it equals the demand of 600–2700 people. These values are non-negligible, yet they are competitive relative to irrigation requirements for crops such as potatoes, which can reach 3000–4500 m3 per hectare annually.
Manifava reports that potato production in Naxos declined sharply from 4000 tons in 2023 to only 1800 tons in 2024 [49]. By comparison, the water used annually for swimming pools could alternatively support the production of 400–800 tons of potatoes, highlighting the competitive nature of local water uses.
However, according to the estimation of the Municipality of Naxos for the permanent population [50] and data on tourist presence on the island [51,52] (Figure 8a), annual domestic water consumption ranges from 376,000 to 1,300,000 m3 for permanent residents and from 177,000 to 612,000 m3 for tourists.
Ιn addition, estimates of 2024 agricultural production—substantially reduced by drought—combined with typical crop water footprint values from available databases [53] indicate a total agricultural water footprint of approximately 11,215,000 m3 [54,55,56] (Figure 8b). With no significant industrial activity in the area, this distribution aligns with global patterns, where domestic use accounts for 10–15% and agriculture and industry for 85–90% of total water demand. By comparison, swimming pools consume only 98,000–124,000 m3 annually, representing less than 1% of the total water use. Thus, although swimming pools are often perceived as emblematic of unsustainable consumption, the evidence shows they are not the primary driver of water scarcity in these regions.
The nexus perspective highlights important trade-offs. Pool water use not only draws on limited freshwater resources but also entails significant energy demand, especially when desalination is required. In Naxos, pools consume an estimated 384–846 MWh annually, comparable to the electricity needs of 60–140 residents. Moreover, the water volumes allocated to pools could irrigate 27–40 hectares of potato crops, yielding food sufficient for 700–1500 people per year. These comparisons underline that swimming pools’ water consumption, although marginal in absolute terms, intersect with critical resource systems and therefore cannot be ignored.
An additional factor shaping the debate on swimming pools is their visibility. Unlike domestic consumption, which is dispersed across households and largely hidden in sewage systems, or agricultural irrigation, which occurs in remote fields, pools are concentrated, conspicuous, and strongly associated with luxury. This visibility may create a perception bias, leading to disproportionate criticism relative to their actual hydrological impact. Such biases can influence public opinion and policy debates [57], potentially diverting attention away from less visible but more significant water demands. Recognizing this discrepancy between perception and reality is essential for designing balanced water management strategies that address the largest pressures without neglecting symbolic uses that can be mitigated through targeted measures.
A nuanced view must consider the profile of pool-owning properties, often luxury resorts or high-end residences in tourist areas. These entities exhibit significantly higher overall water consumption—up to one-third more per occupant than average households—due to additional amenities like extensive landscaping, spas, and gardens. In Mediterranean contexts, hotel water use can be 60–111% higher per bed space in higher-star categories compared to standard accommodations [58,59,60], amplifying local demand and necessitating differentiated management strategies for such properties.
Policy implications of pool water use within the WEF nexus are profound, particularly in desalination-dependent Mediterranean regions. Direct links include energy-intensive desalination, competing with renewable energy goals, potentially increasing regional energy demand by 5-10% in tourist-heavy areas. For agriculture, water diverted to pools represents foregone irrigation, equating to lost potato yields of 400–800 tones in Naxos, which could undermine food security and self-sufficiency amid droughts. Long-term policies should prioritize integrated nexus frameworks, such as subsidies for low-energy desalination or zoning laws favoring rainwater-fed pools, to foster resilience in Mediterranean basins [61,62].
Rainwater harvesting, while requiring large collection areas relative to pool surfaces, could substantially offset demand, particularly under maintenance practices aligned with Scenario 2 (one-third annual renewal). Since pools are typically co-located with residences or hotels, integrating harvesting infrastructure into building design represents a feasible pathway to reduce competition with domestic and agricultural water uses. Such measures could align luxury amenities with sustainable tourism practices, easing public concerns while reducing pressure on local water supplies.
While rainwater harvesting offers promise, real-world constraints must be addressed for viable implementation. Initial setup costs can be potentially offset by long-term savings but can be prohibitive for small operators without subsidies. Water quality standards (e.g., EU Directive 2006/7/EC [63] and Regulation 2020/741 on minimum requirements for water reuse [64]) require treatment to prevent contamination, adding 10–20% to operational expenses; however, this is not clearly needed in rainwater harvesting [65]. These factors ground recommendations in practicality, suggesting incentives like tax breaks to overcome barriers in water-scarce regions.
Practical examples from other Mediterranean countries demonstrate the viability of these measures. In Spain, pilot projects in Alicante have implemented rooftop rainwater harvesting for urban non-potable uses, including pools, reducing pollution and dependency on mains water by collecting runoff effectively [66]. Similarly, in Ibiza, ground-runoff harvesting systems in micro-catchments have increased water availability for isolated households with pools, proving cost-effective in hilly terrains [67]. In Italy, initiatives under EU LIFE projects promote rainwater collection for tourism amenities, integrating it with reuse systems to address scarcity [68]. These cases highlight scalable solutions adaptable to Greek contexts, enhancing sustainability in tourism-driven regions.
Public awareness campaigns can effectively mitigate this perception bias by educating stakeholders on relative contributions to water scarcity. For instance, campaigns in Mediterranean regions could highlight data-driven comparisons, emphasizing agriculture’s dominant role over pools’ minor share, while promoting best practices like efficient pool management. Such initiatives, targeted at tourists, locals, and operators, have succeeded in Greece and beyond by fostering behavioral changes, such as reduced domestic waste, ultimately aligning perceptions with hydrological realities and supporting sustainable tourism policies [69].
Several limitations should be acknowledged. Pool depths were inferred from regulatory practices rather than measured, which introduces uncertainty in volume estimates. To enhance the reliability of these satellite-derived estimates, future comparisons with field data, such as municipal registries or on-site surveys, are recommended. For instance, studies in comparable Mediterranean regions, like urban Spain, suggest satellite-based pool counts typically align within 10–15% of municipal records, with discrepancies often due to undocumented private pools [58,70,71]. In the absence of accessible registries for West Mani and Naxos, our counts of 354 and 556 pools, respectively, could be validated against local permitting records or operator surveys, potentially revealing unregistered constructions which are common in tourism-driven areas. Furthermore, the two scenarios applied represent broad categories, whereas, in practice, maintenance practices may vary. Finally, this study focused on two representative regions; expanding the analysis to other islands and coastal areas would help assess whether the findings are generalizable across the Mediterranean.

5. Conclusions

This study demonstrates that while swimming pools are highly visible consumers of water in touristic regions, their contribution to overall scarcity is modest compared to domestic and agricultural demands. Household consumption, much of which goes unnoticed in daily use, and irrigation for crops such as potatoes require far greater volumes of water. Indicatively, the amount of water a person consumes in a year is enough for (4–19) m2 pool. Similarly, the demands of agriculture are also significant, and supporting agricultural production requires rational planning and conservation of water resources. For example, the amount of water consumed by 1 ha of potatoes in a year for irrigation is enough to fill a pool of approximately 1500–3000 m2.
The visibility of swimming pools often amplifies public concerns, yet their hydrological burden can be managed effectively. Rainwater harvesting, which is particularly feasible in residential and hotel settings, could provide a self-sufficient water source for pools and mitigate competition with essential uses.
Overall, this study suggests that swimming pools, though highly visible and often criticized, play a secondary role in water scarcity compared to domestic consumption and agriculture. Nevertheless, because they intersect with energy use and food production, they remain relevant within integrated water management frameworks. Addressing them through targeted measures like rainwater harvesting can contribute to sustainable tourism development without overshadowing the need to manage larger, less visible water demands.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/w17202934/s1. Sources for Figure 2: The location of pools indicated by yellow landmarks in (a) West Mani and (b) Naxos Island; Figure 3: Examples of the spatial identification process of the pools indicated in blue in (a) West Mani and (b) Naxos Island (.kmz files).

Author Contributions

Conceptualization, G.-F.S.; methodology, G.-F.S.; software, G.-F.S. and E.P.; validation, G.-F.S., E.P. and T.I.; formal analysis, G.-F.S. and E.P.; investigation, G.-F.S. and E.P.; resources, G.-F.S. and E.P.; data curation, G.-F.S. and E.P.; writing—original draft preparation, G.-F.S., E.P. and T.I.; writing—review and editing, G.-F.S., E.P. and T.I.; visualization, G.-F.S. and E.P. All authors have read and agreed to the published version of the manuscript.

Funding

This research has received funding from the European Union’s Horizon Europe research and innovation programme under grant agreement No. 101181779 (WATERSENS—Development of Innovative Decentralized Technologies and New Co-Created Governance Models for Water Sensitive Communities). Views and opinions expressed are however those of the author only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.

Data Availability Statement

This study created new data sets by detailed inspection of satellite images. The data sets are uploaded as Supplementary Materials.

Acknowledgments

We are grateful to Ioannis Benekos and Christos Belogianneas for their notable comments and their support.

Conflicts of Interest

The authors declare no conflict of interest.

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Water 17 02934 g001
Figure 1. Geographical location of Greece (Europe) and the location of West Mani and Naxos Island, the two case study regions in Southern Greece [27,28].
Figure 1. Geographical location of Greece (Europe) and the location of West Mani and Naxos Island, the two case study regions in Southern Greece [27,28].
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Figure 2. The location of pools indicated by yellow landmarks in (a) West Mani and (b) Naxos Island [28]. The related data in .kmz file are provided in Supplementary Material.
Figure 2. The location of pools indicated by yellow landmarks in (a) West Mani and (b) Naxos Island [28]. The related data in .kmz file are provided in Supplementary Material.
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Figure 3. Examples of the spatial identification process of the pools indicated in blue in (a) West Mani and (b) Naxos Island [28]. The related data in .kmz file are provided in Supplementary Material.
Figure 3. Examples of the spatial identification process of the pools indicated in blue in (a) West Mani and (b) Naxos Island [28]. The related data in .kmz file are provided in Supplementary Material.
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Figure 4. The number of the pools and their corresponding total surface. Below 50 m2, the depth is considered 1.5 m and above 50 m2 the depth is considered 2 m. (a) West Mani and (b) Naxos Island.
Figure 4. The number of the pools and their corresponding total surface. Below 50 m2, the depth is considered 1.5 m and above 50 m2 the depth is considered 2 m. (a) West Mani and (b) Naxos Island.
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Figure 5. Water use for swimming pools in West Mani. (a) Scenario 1: distribution of water losses during one year for current pools (m3); (b) Scenario 2: distribution of water losses during one year for current pools (m3).
Figure 5. Water use for swimming pools in West Mani. (a) Scenario 1: distribution of water losses during one year for current pools (m3); (b) Scenario 2: distribution of water losses during one year for current pools (m3).
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Figure 6. Water use for swimming pools on island of Naxos. (a) Scenario 1: distribution of water losses during one year for current pools (m3); (b) Scenario 2: distribution of water losses during one year for current pools (m3).
Figure 6. Water use for swimming pools on island of Naxos. (a) Scenario 1: distribution of water losses during one year for current pools (m3); (b) Scenario 2: distribution of water losses during one year for current pools (m3).
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Figure 7. Average annual values of water consumption for domestic use or for swimming pools in WEF nexus on island of Naxos. (a) Water provided by desalination. (b) Optimization of water use with rain harvesting and alternative water use for food production.
Figure 7. Average annual values of water consumption for domestic use or for swimming pools in WEF nexus on island of Naxos. (a) Water provided by desalination. (b) Optimization of water use with rain harvesting and alternative water use for food production.
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Figure 8. (a) Presence of the inhabitants and tourists on the island of Naxos. (b) Primary production of basic goods, water footprint (m3/ton) for each product, and cumulative water footprint of primary production.
Figure 8. (a) Presence of the inhabitants and tourists on the island of Naxos. (b) Primary production of basic goods, water footprint (m3/ton) for each product, and cumulative water footprint of primary production.
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Table 1. Summary of the results for water use for swimming pools for the island of Naxos and West Mani.
Table 1. Summary of the results for water use for swimming pools for the island of Naxos and West Mani.
Scenario 1 Annual Consumption (People)Scenario 2 Annual Consumption (People)
West Mani50,551 m3 800–276939,446 m3 624–2161
Naxos123,931 m3 1962–679097,812 m3 1549–5359
Table 2. Summary of the results for water use for swimming pools for the island of Naxos standardized in m2.
Table 2. Summary of the results for water use for swimming pools for the island of Naxos standardized in m2.
Scenario 1 Days of a Person’s ConsumptionScenario 2 Days of a Person’s Consumption
West ManiDepth 1.5 m3.91 m3 22–783.05 m3 17–60
Depth 2 m5.21 m3 30–1044.06 m3 23–81
NaxosDepth 1.5 m3.93 m3 22–783.13 m3 18–62
Depth 2 m5.11 m3 29–1024.01 m3 23–80
Table 3. Annual energy use for swimming pools for West Mani.
Table 3. Annual energy use for swimming pools for West Mani.
Scenario 1 (Total)Annual Consumption (People)Scenario 2 (Total)Annual Consumption (People)
Energy needs (depth 1.5 m)Operational needs 285 MWh 47365 MWh 60
Desalination159 MWh 26124 MWh 20
Energy needs (depth 2 m)Operational needs 152 MWh 25194 MWh 32
Desalination94.0 MWh 1573.4 MWh 12
Table 4. Annual energy use for swimming pools for the island of Naxos.
Table 4. Annual energy use for swimming pools for the island of Naxos.
Scenario 1 (Total)Annual Consumption (People)Scenario 2 (Total)Annual Consumption (People)
Energy needs (depth 1.5 m)Operational needs 384 MWh 64491 MWh 81
Desalination218 MWh 36174 MWh 28
Energy needs (depth 2 m)Operational needs 661 MWh 110846 MWh 140
Desalination402 MWh 66315 MWh 52
Table 5. Annual energy use for swimming pools standardized in m2 for West Mani.
Table 5. Annual energy use for swimming pools standardized in m2 for West Mani.
Scenario 1 (Total)Days of a Person’s ConsumptionScenario 2 (Total)Days of a Person’s Consumption
Energy needs (depth 1.5 m)Operational needs 35.1 kWh 2.1344.9 kWh2.73
Desalination19.5 kWh1.1915.2 kWh0.93
Energy needs (depth 2 m)Operational needs 42.0 kWh2.5553.7 kWh3.27
Desalination26.0 kWh1.5820.3 kWh1.24
Table 6. Annual energy use for swimming pools standardized in m2 for the island of Naxos.
Table 6. Annual energy use for swimming pools standardized in m2 for the island of Naxos.
Scenario 1 (Total)Days of a Person’s ConsumptionScenario 2 (Total)Days of a Person’s Consumption
Energy needs (depth 1.5 m)Operational needs 34.6 kWh 2.1144.3 kWh2.69
Desalination19.6 kWh1.1915.7 kWh0.95
Energy needs (depth 2 m)Operational needs 42.0 kWh2.5653.8 kWh3.27
Desalination25.5 kWh1.5520.0 kWh1.22
Table 7. WEF analysis for swimming pools (1.5 m depth) on the island of Naxos considering local food production.
Table 7. WEF analysis for swimming pools (1.5 m depth) on the island of Naxos considering local food production.
Scenario 1 (Total)Scenario 1 (m2)Scenario 2 (Total)Scenario 2 (m2)
Water use for swimming pools43,562 m3 3.93 m3 34,767 m3 3.13 m3
Area of potato yield irrigated by the water use for swimming pools9.68–14.5 ha 8.72–13.1 m2 7.73–11.6 ha 6.96–10.4 m2
Production of potato yield 363–436 tons21.8–58.9 kg290–348 tons17.4–47.0 kg
Energy contained in the potato 280–335 M kcal
1.17–1.40 TJ		16,794–45,343 kcal
70.2–190 MJ		223–268 M kcal
0.933–1.12 TJ		13,403–36,189 kcal
56.1–151 MJ
People who could be fed by these potatoes 255–510 people (annually)5.60–25.2 (days for one human)203–407 people (annually)4.47–20.1 (days for one human)
Table 8. WEF analysis for swimming pools (2 m depth) on the island of Naxos considering local food production.
Table 8. WEF analysis for swimming pools (2 m depth) on the island of Naxos considering local food production.
Scenario 1 (Total)Scenario 1 (m2)Scenario 2 (Total)Scenario 2 (m2)
Water use for swimming pools80,370 m3 5.11 m3 63,045 m3 4.01 m3
Area of potato yield irrigated by the water use for swimming pools17.9–26.8 ha11.4–17.0 m2 14.0–21.0 ha 8.91–13.4 m2
Production of potato yield 670–804 tons28.4–76.6 kg525–630 tons22.3–60.1 kg
Energy contained in the potato 516–619 M kcal
2.16–2.59 TJ		21,857–59,014 kcal 91.4–247 MJ405–485 M kcal
1.69–2.03 TJ		17,146–46,293 kcal
71.7–194 MJ
People who could be fed by these potatoes 470–941 people (annually)7.29–32.8 (days for one human)369–738 people (annually)5.72–25.7 (days for one human)
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Sargentis, G.-F.; Palamarczuk, E.; Iliopoulou, T. Swimming Pools in Water Scarce Regions: A Real or Exaggerated Water Problem? Case Studies from Southern Greece. Water 2025, 17, 2934. https://doi.org/10.3390/w17202934

AMA Style

Sargentis G-F, Palamarczuk E, Iliopoulou T. Swimming Pools in Water Scarce Regions: A Real or Exaggerated Water Problem? Case Studies from Southern Greece. Water. 2025; 17(20):2934. https://doi.org/10.3390/w17202934

Chicago/Turabian Style

Sargentis, G.-Fivos, Emma Palamarczuk, and Theano Iliopoulou. 2025. "Swimming Pools in Water Scarce Regions: A Real or Exaggerated Water Problem? Case Studies from Southern Greece" Water 17, no. 20: 2934. https://doi.org/10.3390/w17202934

APA Style

Sargentis, G.-F., Palamarczuk, E., & Iliopoulou, T. (2025). Swimming Pools in Water Scarce Regions: A Real or Exaggerated Water Problem? Case Studies from Southern Greece. Water, 17(20), 2934. https://doi.org/10.3390/w17202934

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