The Mirage of Drinking Water Security in Chilean Patagonia: A Socio-Ecological Perspective

Abstract

This study investigates the paradoxical water security challenges in western Chilean Patagonia, where the regional abundance of water resources masks significant vulnerabilities of drinking water systems. We conducted an integrated socio-hydrological analysis over rural (APR) and urban (APU) drinking water systems, which provide water to approximately 846,000 people. We georeferenced 343 drinking water intake points, from which 51.6% are sourced from groundwater, and 45.8% from surface waters (2.6% other sources). An eco-hydrological characterization was conducted on the 147 watersheds supplying water to the surface intake points. Watersheds were characterized by their main hydrological, morphological, and land cover features, as well as by their level of anthropization (AI) and water stress index (WSI). Social dimensions were captured through structured interviews with 117 APR directorate leaders regarding their perceptions of infrastructure, governance, climate change, and local water management challenges. Our findings suggest that water availability in Patagonia creates a mirage of water security. AI and WSI indicate high variability in the status of water sources, with 25% of watersheds showing high levels of anthropization and 33% with medium to high levels of water stress, making it relevant to explore the results through a combination of hydroclimatic, longitudinal, and latitudinal gradients. A novel analysis linking WSI and AI to governance perceptions was conducted, finding significant inverse correlations between WSI and both technical capacity and users’ participation. Despite the region’s evident abundance of water resources, rural communities consistently express concerns regarding supply sustainability, infrastructure deficiencies, insufficient technical support, and climate change risks to current and future water availability, all of which constrain water security in Chilean Patagonia.

1. Introduction

1.1. Drinking Water in the Global Context

Access to safe drinking water, sanitation, and hygiene represent the most basic human needs for health care and well-being [1]. The Sustainable Development Goals (SDGs [1]) established ambitious targets for access to safe drinking water in a context of significant population growth in underserved and resource-constrained environments. SDG 6 [1] addresses water issues and sets a goal to implement integrated water resources management at all levels, but the reporting system shows slow progress, which indicates that changes are needed [2]. Yet, a decade after adopting SDG 6 to ensure safe and affordable drinking water, an estimated 4.4 billion people lack safely managed drinking water services [1,3]. Current measures do not suffice for addressing the global water crisis or achieving SDG 6 on water and the water-related SDGs (e.g., food, health, and climate [1]). Effective stewardship of water resources is a critical global need, as signaled by its recognition as an important factor of the SDGs [2]. Implementation challenges include lack of clear vision and political commitment, but also paucity of coordination and financing, weak institutional and professional capacity, insufficient data-sharing and monitoring, and outdated and ineffective legal frameworks [1,4]. Progress has required shifts from single-purpose methods toward integrative approaches, because water connects societal and environmental systems, and emphasis must be placed on the involvement of all stakeholders [2].

The quality and quantity of drinking water is a fundamental part of the SDGs [1]. However, the provision of safe drinking water currently faces a series of challenges and conflicts with human activities. There is increasing competition for water between the economy and the environment [5,6]. With changing water supplies and climate change increasing the frequency and magnitude of extreme hydrological events (e.g., floods and droughts) and making them less predictable, much better information is needed for effective water governance [2,6]. In an era of growing climate change impacts, there is an increasing need to grasp the complex connection between human society and hydrological systems [7,8,9].

1.2. Socio-Hydrology and Water Governance

Socio-hydrology, the science of people and water [10], aims to understand the dynamics and co-evolution of coupled human–water systems [11]. The field of socio-hydrology was introduced as one approach of the socio-ecological framework [7,9,12] that can foster a deeper understanding of the complex interactions between humans and water systems, while advocating for approaches to water resources management that truly integrate socio-economic and political factors [5]. Socio-hydrology is an interdisciplinary area between hydrology, sociology, and economics that provides essential insights to uncover how people’s behavior impacts water, climate, and natural resources [5,11]. Socio-hydrology explores the coevolution and self-organization of people in the landscape, also with respect to water availability, to provide insights for decision-making and policy intervention for building resilience at different levels [10,11,13]. Socio-hydrological principles explain how human behavior, cultural norms, and governance structures intersect with hydrological processes [5], enabling the development of inclusive policies, equitable agreements, and cooperative strategies for sustainable water use and conflict resolution [5,10]. Socio-hydrology aims to address the complex aspects of social diversity, power dynamics, trust, cultural values, and cognitive biases that have a significant impact on how individuals modify and adapt to evolving hydrological systems [13]. This includes developing common methodologies that can be shared across disciplines to better understand the interplay between water resources and society [5].

Governance, once seen as a background administrative process, is now recognized as a key determinant of freshwater security, defined not only as access to water resources but also the ability to manage risks, ensure affordability, and support long-term ecosystem resilience [14,15]. Water governance refers to the “ways in which societies organize themselves to make decisions and take action regarding water”, a definition that reflects the growing importance of non-state actors (e.g., community and private sector) as well as the influence of decisions and actions outside of the water sector [3]. Considerations of social distribution and politics feature strongly in how governance can serve and favor particular interests and powerful groups [3,5,15]. Several decades into these debates, global reporting continues to illustrate the limited progress we are making to protect ecosystems, conserve scarce resources, or provide basic drinking water to the most vulnerable [3,5,14,16]. Furthermore, a socio-hydrological approach must incorporate the drivers of global change to strengthen pathways toward water governance and security [7,8].

Effective water governance requires information for measuring, monitoring, and understanding [6], while the governance capacity of stakeholders can be enhanced through processes specifically designed to promote learning and to build competence in understanding the system they want to govern [9,17]. Institutional structures and decision-making processes should adopt an adaptive governance approach, connecting stakeholders across multiple scales to manage the conflicting stakeholder values and knowledge uncertainties that characterize the management of complex resource systems [13,18].

1.3. Water Security in Chile

The United Nations Water Resources Framework defines water security as the capacity of a population to safeguard access to sufficient quantities of water of acceptable quality for sustaining livelihoods, promoting human well-being, fostering socio-economic development, and preserving ecosystems [19]. In Chile, this concept has been adopted in the Framework Law on Climate Change (MMA 2022) and the policy instruments derived from that law to orient water management and adaptation goals [20]. By focusing on achieving sustainable access to safe quality water while protecting against water-related hazards for people, the economy, and the environment alike, water security can be seen as an overall societal aim of water governance [14,16].

These complex and interacting elements are undeniably relevant, but the practical challenge lies in breaking down each component, together with corresponding observations, analysis, and implementation. In Chile, recent efforts have been made in this regard, with the development of national inventories of water availability and sectoral water uses, as well as diagnoses of water stress over major basins [21,22]. Despite these advances, critical information and knowledge gaps remain open, particularly regarding access to drinking water in rural and urban communities.

Chilean rural and urban drinking water systems are considered a benchmark in Latin America, as they have the highest coverage and implementation rates [23,24]. In southern Chile (40° S—55° S), most of these systems rely on surface water sources from small watersheds (<10,000 hectares), or groundwater sources, for which there is poor information regarding their origin, quality, and future availability. Despite high water availability levels in this region [22], water supply for both the rural and urban population is at risk due to the synergistic effects of various components of global change, such as climate change, land use change, soil erosion, and desertification, along with the increasing biological and chemical contamination of watercourses and water bodies [25,26,27,28]. This affects the quantity and quality of water for human use obtained from surface water sources [29,30,31,32], particularly those streams originating in mountain watersheds.

Particularly in Chilean Patagonia (40° S—55° S), the main pressures on water sources are related to land use change [33] driven by livestock farming, forestry, real estate development, and public and private infrastructure, while pollution from untreated wastewater represents a growing threat. In general, the people in charge of managing urban and rural drinking water systems do not own the land where the water sources are located, nor the upstream watershed to the intake points. Therefore, they have no control over the activities carried out by land and water owners in the watershed. Their function is limited to the collection, sanitation, and distribution of water to the population enrolled in each drinking water system [28]. Furthermore, Chile’s water allocation and trading system is based on a water use rights market, with limited regulatory and oversight mechanisms. In this scheme, a fixed volume of water to be granted as permanent or temporary water use rights is calculated based on statistics of historical river flow records, if available, or empirical estimates, if not [34]. Studies have shown that this allocation scheme is not adequate under the current and projected hydroclimatic conditions in Chile [26,34], and that the protection of environmental flows considered when allocating water use rights is not compatible with long-term water security goals [35]. Considering these water allocation scheme limitations, the provision of drinking water remains strongly influenced by the actions of private or public (public lands) third parties who hold property rights over the watersheds that supply these systems or who hold water rights in surface watercourses (streams or rivers) located upstream of the intakes of drinking water systems, highlighting the fragile stability of these systems.

Currently, big knowledge gaps exist regarding basic information on locations of water intakes along the hydrological network, necessary for modeling the contributing watersheds, but there is also a lack of adequate information on the quality and quantity of water from sources for human use in Chilean Patagonia. Rural drinking water (APR, from its Spanish acronym) and urban drinking water (APU) systems usually do not monitor flow rates (water quantity), and quality analyses are infrequently performed. This information gap becomes increasingly critical in a context of global change, where the availability and quality of water sources for human use may be negatively affected [1,33].

This preliminary analysis supports the prospect of integrating socio-hydrological factors by recognizing the social components of water management, including human perception, cognition, behavior, and institutions [11]. Research should advance to representative hydrology, aiming to characterize and learn from the similarities and differences between watersheds in different places, and interpret these in terms of underlying climate–landscape–human controls in a changing world [13,18]. In the context of socio-hydrology, this implies a comparative analysis of human–water interactions across socio-economic gradients, as well as climatic and other gradients, to map any spatial or regional differences back to processes and their temporal dynamics [10].

The relationship between water security and water governance across different water-using sectors remains under-researched [14,16]. One of the key challenges in addressing human water access is to jointly analyze different components of the human–water system, including the geography (the physical nature of the watersheds that capture and deliver water at the point of intake for human use), the hydrological cycle and the local biosphere (which regulate water flows through the basin), and the social component, which includes land and water use regulations, as well as human activities on land and water [14,36], which alter the local water cycle and its interaction with watersheds in different ways [36].

As a synthesis, water security can be seen to entail two parallel objectives: first, enabling the sustainable use and management of water for human and the ecosystem’s well-being, livelihoods, and development; and second, protecting societies, economies, and ecosystems from water-related hazards at all levels and scales [14,16]. Water security as a concept helps to both assess and clarify governance priorities, while well-functioning adaptive governance with the engagement of key actors is a prerequisite for broader water security [13,14,16,18].

1.4. Scope of This Research

To tackle some of the challenges highlighted here, we adopt a socio-hydrological approach (derived from a coupled social–ecological system [12]) to study the link between social and hydrological factors affecting a relevant component of water security in southern Chile. Specifically, we aim to (i) identify and characterize the water sources of urban and rural drinking water systems, (ii) assess the perceptions of rural system leaders regarding governance and climate change protections, and (iii) explore a way to categorize water security levels, considering the socio-hydrological approach [10,36], in a broader context of global change [13].

To achieve these objectives, our research questions are as follows:

(1)

Where are drinking water systems located in western Patagonia, and what are the main characteristics of surface water sources?

(2)

How do leaders of rural drinking water systems perceive water security challenges regarding quality, quantity, and governance priorities, and what geographic and system characteristics influence these perceptions in Chilean Patagonia?

(3)

How can water security be assessed from a socio-hydrological perspective in a territory where the general assumption of abundant water resources contradicts a vast and complex geography and climate gradient?

2. Materials and Methods

The study was conducted in western Chilean Patagonia, defined for these purposes by the administrative boundaries of the Los Lagos, Aysén, and Magallanes regions (40–55° S; Figure 1).

2.1. Databases

A bibliographic review of the scientific and technical literature related to Water Security and the APR and APU systems in southern Chile was conducted through an internet search. Information related to water management was also requested from public services through the Transparency Law. Databases related to water management were obtained, specifically the national database of Rural Sanitation Services from the Directorate of Hydraulic Works (DOH), the official registry of water use rights (WURs) and the Chilean limits of the macro-basins (Figure 1) of the General Directorate of Water (DGA). These datasets were reviewed, cleaned, and organized manually. Once this initial dataset was compiled, we conducted a field work campaign during February and March 2025 to visit and confirm the locations and coordinates of all the APR and APU water intakes in the study area.

2.2. Geospatial Study

For the characterization and eco-hydrological analysis of the watersheds contributing to the surface APR and APU systems in western Chilean Patagonia, 343 water intakes with known geographic coordinates were analyzed in the study area. Of the total systems, 309 are APR and 34 are APU. The water source type was divided into 157 surface (48.4%) and 177 groundwater (51.6%) intakes (Figure 1). The remaining nine systems, with sources characterized by rainwater, lakes, or connections to sanitary facilities, were considered not comparable and were not included in the analysis.

For 157 surface intakes, a hydrological, morphological, landscape, and climate characterization of each contributing watershed was conducted to generate a baseline, representing the diversity of the landscape in which the watersheds that supply water to each drinking water system are located. The main elevation data source used in this study was a DEM produced by the Centro de Información de Recursos Naturales (CIREN) based on the ALOS PALSAR DEM, at a spatial resolution of 12.5 m. This DEM was used because of its higher spatial resolution when compared to other freely available DEMs and because it is already mosaiced and masked to the Chilean territory, while also corrected to mean sea level height. In the case of binational catchments (i.e., Río Cochrane, one of the largest within the study) which are incomplete in the aforementioned DEM, the latest NASADEM was used given its ease of access and its reliance on several auxiliary elevation sources to fill and correct data voids and extend its coverage [37], especially in mountainous terrains such as the Andes mountains. The elevation data was downloaded as a mosaic of the complete study area from OpenTopography (www.opentopography.org) and later reprojected to UTM 19S projection in QGIS 3.40.7. Other information sources include the Native Forest Cadastre [38], WURs, the Daily Precipitation Product from the CR2MET Database [22,39], and the geographic coordinates of the APR catchments recorded in the field.

The characterization of surface water sources included the hydrological, morphological, landscape and climatic characterization of contributing watersheds using the most appropriate satellite-based Digital Elevation Model (DEM) for each case, and the Native Forest Cadastre [38] for landscape analysis, auxiliary cadastral information, and gridded climate products. Hydrologically and morphometrically, the main channel was identified and the Strahler order calculated for the complete drainage network, along with morphometric parameters [32] derived from the DEM (

Table 1. Watershed classification into ranges of the different morphometric and land use parameters, showing under 1, 2, and 3 the percentage relative to the total number of watersheds studied. Details of classes for each variable are in parentheses.

Variable	1	2	3
Size (0–10; 10–100; >100 km2)	63.3	25.9	10.8
Unevenness (0–500; 500–1500; >1500 m)	51.8	38.6	9.6
Average slope (0–30; 30–45; >45%)	69.3	19.9	10.8
Form Factor (0–0.3; 0.3–0.6; >0.6)	58.4	11.4	30.1
Compactness index (0–1.25; 1.25–1.75; >1.75)	5.4	27.7	66.9
Orographic coefficient (0–0.1; 0.1–0.3; >0.3)	76.5	12.7	10.8
Strahler Order (1–2; 3–4; >4)	61.4	30.1	8.4
Annual precipitation (0–1000; 1000–2500; >2500 mm)	14.5	64.5	21.1
Native Forest (0–33; 33–66; >66% of watershed surface)	22.3	34.9	42.8
Anthropization Index (0–0.25; 0.25–0.50; >0.50)	44.6	30.1	25.3
Water availability (0–10; 10–1000; >1000 L/s)	10.3	60.9	28.8

). In terms of landscape, 14 land use/land cover (LULC) categories that represent the general land cover composition throughout the complete study area were generated through aggregation of the “LAND_USE” category of the Native Forest Inventory [38], from which the current LULC composition, along with the Anthropization Index [40] at watershed level, were calculated.

The anthropization index (AI) is based on the degree of land use intensity derived from the LULC maps. To build the AI, first, the LULC categories were grouped into eight anthropization classes [40]. Consecutively, the anthropization classes were normalized from 0 to 1. Finally, the different AI normalized values were assigned to each pixel of the LULC maps to build AI maps at different times and landscapes under study using the raster library of the R 4.4.2 software [40]. The interpretation of the AI is as follows: values close to 0 indicate a landscape with low anthropization, and 1 is a highly anthropized landscape.

Also, the presence of areas under official protection within each watershed was identified, as well as the number of WURs assigned and the associated accumulated water flow. For climate characterization, the Average Annual Precipitation for the period 1990–2020 was calculated using CR2MET data [39], along with monthly precipitation data for the same time period.

2.3. WSI Analysis

A water use to availability water stress index (WSI) was adapted from [22,41] and calculated for each contributing watershed of surface APR and APU systems.

Two WSIs were derived based on a common water availability derived from CR2MET and two different representations of water uses within the watersheds: (i) WSI.da, which considers the total consumptive WURs allocated within each water course, and (ii) WSI.ap, which considers the actual estimations of water uses from land use activities within each watershed obtained from the CR2WU product [22], and estimated water use for drinking water associated with each drinking water system.

In this way, WSI.da reflects a potential water stress arising from legally authorized consumptive flow within the contributing watershed, whereas WSI.ap represents an estimation of actual stress due to the major consumptive activities in the watershed. In both cases, the indices were computed using basin-wide water availability [22,41], estimated as the differences between long-term mean (1990–2020 period) precipitation and naturalized evapotranspiration, with values converted to L/s.

Drinking water for APR systems was estimated from the number of household connections per APR, multiplied by 3.1 (average number of inhabitants per household, according to Chile’s National Statistics Institute) and by a per capita water use rate of 0.02 L/s (according to [23]).

Following the methodology explained in [22], consumptive water uses from land use sectors, including irrigated agriculture and rainfed activities (e.g., forestry), is estimated as the difference between mean (1990–2020) evapotranspiration rates simulated under two scenarios: one with actual land use activities and another with a naturalized landscape [41].

To assess differences in WSI levels within groups (geoforms, macro-basins, availability, precipitation, basin area), we first tested the data distribution using the Shapiro–Wilk test, which showed non-normality. Therefore, the nonparametric Kruskal–Wallis test was used to detect significant differences among groups and, if detected, the Wilcox test with Bonferroni adjustment was used to identify which groups differed from each other. To reduce the presence of outliers, mean WSI values distribution for the 2015–2020 period was analyzed to define a representative threshold value that represents outliers. After that, all values above WSI = 100% were excluded from the analysis.

The software and packages used to develop the geospatial analysis were: Whitebox Tools Library for R [42,43], R4.4.2, RStudio 2025.05.1, and QGIS 3.40.7.

2.4. Social Study

This study employed a mixed-methods approach to characterize rural water supply systems (APR) and assess water security perceptions among governance participants in Chilean Patagonia. The study population comprised the governance committees associated with APR drinking water systems across western Chilean Patagonia, based on a comprehensive database of 333 systems provided by DOH: 275 in the Los Lagos region, 47 in the Aysén region, and 11 in the Magallanes region. Structured surveys were administered via telephone through the Qualtrics platform to one representative from each APR governance committee (Presidents, Secretaries, and Treasurers) during six weeks of fieldwork beginning in mid-February 2025. Face-to-face interviews were deemed impractical due to the geographical dispersion of APR systems across Chilean Patagonia, where many communities are accessible only via challenging terrain, unpaved roads, or ferry connections. Meta-analytic research demonstrates that telephone surveys achieve comparable response rates (67.2%) and data quality (70.3%) to face-to-face interviews, while providing logistical advantages including enhanced participant anonymity and the elimination of travel-related costs and safety concerns [44,45,46]. Telephone surveys can be conducted centrally, allowing population coverage to be more extensive than face-to-face surveys [45]. Given that 21.5% of Chilean households rely exclusively on mobile access for connectivity, telephone access is often more reliable than internet-based alternatives in rural areas. The contact protocol involved calling each participant one to five times until successfully reached. No messages were left on answering machines or with intermediary contacts; instead, a callback was indicated. After five unsuccessful attempts, participants were classified as unreachable.

The survey instrument consisted of seven thematic blocks: (1) informed consent, (2) APR system characterization including management structure, infrastructure, water sources, and service coverage, (3) water supply and security assessments, (4) governance and community participation mechanisms, (5) watershed dynamics and hydrographic network mapping, (6) water demand patterns at both system and property levels, and (7) knowledge and perceptions of nature-based solutions for water security improvement. The instrument employed multiple question formats including Likert scales (−4 to +4), multiple choice, open-ended responses, and detailed water consumption data collection. This paper focuses on the results of Section 2, Section 3 and Section 4.

Individual demographic characteristics were deliberately excluded from this organization-focused survey instrument for methodological and ethical reasons [47]. As our research questions focused on institutional perceptions and system-level characteristics rather than individual attributes, the unit of analysis was the APR system and its governance structure, not the individual leader. Governance committee participants were chosen for this organizational survey because of their institutional knowledge, with variables conceptualized at a macro-organizational level rather than individual characteristics [48]. Including demographic variables would have shifted focus from organizational governance capacity to personal characteristics, potentially obscuring the institutional dynamics central to our research objectives [49,50]. Additionally, demographic questions raised privacy concerns in small rural communities (typically 50–200 residents) where governance leaders are easily identifiable, and combining such data with governance roles could have compromised participant anonymity and affected response honesty. Finally, governance committee members serve as elected representatives whose responses reflect collective institutional knowledge and community readiness rather than personal perspectives, with their legitimacy stemming from formal roles and community mandate rather than individual characteristics [51].

Management priority, water quality, and water security were measured on ordinal and interval scales. Several variables were non-normally distributed and the assumption of equal variances across groups could not be guaranteed; therefore, we used non-parametric tests: Mann–Whitney U for two-group comparisons and Kruskal–Wallis H for multiple groups, with Bonferroni-adjusted post hoc tests. Effect sizes were calculated using rank biserial correlation (r) and eta squared (η²). Significance was set at p < 0.05 (p < 0.01 for high significance). Qualitative interviews enriched the quantitative analysis. The study was approved by the Human Subjects Ethics Committee of the Universidad de Magallanes (Certificate No. 024/CEC-UMAG/2023).

Finally, correlation analysis was used to examine how governance priorities related to watershed biophysical conditions across 54 surface APR systems. The analysis examined relationships between two watershed condition indices and six governance priority variables. Watershed conditions included: (1) anthropization index (AI)—a composite measure of human impact using land use categories, morphometric parameters, and water rights; and (2) water security index (WSI)—the ratio of water demand to availability, with variants for consumptive rights (WSI.da) and estimated actual use (WSI.ap). The perceived importance of the following governance priorities was measured using a 9-point Likert scale (1 = completely unimportant to 9 = completely important): (1) infrastructure, (2) monitoring systems, (3) regulations, (4) user participation, (5) technical capacity, and (6) financial resources. Pearson correlation analysis examined relationships between watershed conditions and governance priorities. Cohen’s traditional effect size guidelines (r = 0.10, 0.30, 0.50) are overly stringent for social science research, where fewer than 3% of correlations reach r = 0.50 [52]. In social contexts, correlations of 0.20–0.35 represent meaningful relationships given the complex, multifactorial nature of social phenomena [53]. Statistical significance was evaluated at p < 0.05 and p < 0.01 levels.

The social components of this study focused on governance perspectives rather than general user experiences, which may not fully capture the breadth of community perceptions regarding water security challenges. Additionally, the exclusion of demographic variables limits our ability to understand how individual characteristics might influence governance perspectives, though this approach was necessary to maintain participant confidentiality in small rural communities and align with our institutional-focused research questions.

3. Results

We identified 334 drinking water intakes in western Chilean Patagonia, of which 309 (90%) correspond to APR systems serving 232,279 people and 34 (10%) are APU systems serving 614,071 people. Of these intakes, 51.6% (165 APR and 12 APU) draw from groundwater sources, while 45.8% (136 APR and 21 APU) rely on surface water (streams and rivers). The 334 surface and groundwater intakes are distributed across the coastal zone (155 systems), the Intermediate Valleys (108 systems), and the Andes foothills (71 systems, Figure 1).

3.1. Watersheds Characterization in Surface APR and APU Systems

Watershed characterization of surface water intakes (N = 157) shows high dispersion in terms of catchment area (Table 1; Appendix A) ranging to slightly less than 800 km², but the majority (63%) are relatively small watersheds, with an area of less than 10 km². Most catchments have a low elevation difference between the highest elevation and capture point (52% are <500 m), average slopes of less than 30% (69%; Table 1), and elongated shape (67% with compactness index < 1.25; 70% with form factor < 0.3). The latter implies slower flood response time compared to rounder watersheds, which are less common (5%).

Regarding the water network, in most cases (61%) channels are order 1 or 2, which is consistent with the relatively small size of watersheds. The terrain morphology within the watersheds (orographic coefficient, Table 1), mostly 0–0.1 (76.5%), slightly affects the water potential and the watershed response to rainfall, suggesting that runoff and water distribution depend largely on the potential energy of the water stored within the watersheds. This latter point is especially relevant, as it indicates that vegetation cover and soil types significantly affect water movement within the watersheds.

Vegetation cover is highly diverse and generally forms a mosaic within the watersheds. Native forest cover is relatively high (>66% total cover) in 43% of the watersheds (Table 1) and medium-high (33–66% total cover) in 35%. This pattern is reflected in the levels of anthropization within the watersheds, which are mostly low (44.6% of the watersheds) or medium (30% of the watersheds). However, there is a group of watersheds (25% of the total) with high levels of anthropization, with higher potential for influencing ecosystem function of water regulation.

Finally, regarding the climate regime of drinking water systems, a relatively high (1000–2500 mm) to very high (>2500 mm) annual rate of precipitation is observed in most cases (85%, Table 1), and the availability of water in the channels exceeds 10 L/s in 90% of the studied watersheds.

While specific groundwater source zones were not characterized, most were located in central valley landforms (48.6%) followed by coast (44.6%), and with very few exceptions (e.g., trans-Andean valleys in more southern latitudes), were located in more densely populated and higher density water supply systems in northern latitudes (40—42° S; Figure 1).

3.2. WSI

The different WSIs used in the analysis allow for the quantification of water stress in the watersheds supplying drinking water systems, under current (WSI.ap) and potential (WSI.da) uses, that is, assuming all WURs granted within the watershed were effectively utilized. The WSI.ap results for the 2015–2020 period indicate a low level of water stress for the majority (87%) of the watersheds, with only 6% classified as highly stressed (Figure 2,

Table 2. Different WSI values showing percentage of watersheds relative to the total number of watersheds studied.

Variable	0–20%	20–40%	>40%
WSI 2015–2020	58.1	15.5	26.5
WSI 2016	59.4	6.5	34.2
WSI.ap 2015–2020	87.1	7.1	5.8
WSI.ap 2016	85.8	2.6	11.6
WSI.da 2015–2020	66.7	10.9	22.4
WSI.da 2016	67.9	5.8	26.3

).

The analysis of the WSI.da values shows a larger number of watersheds with a high level of stress (22%), while 67% remain at a low level (Figure 2, Table 2). Additionally, a WSI analysis was conducted for the exceptionally dry year 2016, which showed an increase in the proportion of watersheds with high levels of water stress from 6 to 11% for WSI.ap and from 22 to 26% for WSI.da (Figure 2 and Table 2). By integrating the different variables into a single index (WSI), the results show a percentage increase in watersheds with high levels of water stress, with 26.5% of the studied watersheds for the 2015–2020 period and 34% for 2016 (Table 2).

When analyzing the average WSI.ap and WSI.da values by landforms, rainfall, area, and water availability in the watersheds (Figure 3), high variability is observed within each established type/range, with several individual watersheds showing high to very high WSI values (>40%). Furthermore, the two WSI calculations (WSI.ap and WSI.da) differ within each range, a contrast that is particularly noticeable when grouped by rainfall and water availability (Figure 3). In medium-to-large watersheds, WSI.da exhibits considerable variability (Figure 3), because a greater number of WURs are correlated with higher variance of mean WURs. The landforms also show significant variability, but high values are particularly noticeable in individual basins in the coastal sector.

Significant differences were identified between the precipitation ranges of 0–1000 mm and >2500 mm (p.dj < 0.05) and 1000–2500 mm and >2500 mm (p.adj < 0.01) in the case of WSI.ap. Regarding WSI.da, significant differences were observed between all precipitation ranges (p < 0.01). Significant differences were also observed between all water availability ranges (p < 0.01), for both WSI.da and WSI.ap. No significant differences were identified between the contributing watershed area ranges, nor in geoforms.

When analyzing the full dataset without categorization, a high dispersion is observed for both indices (WSI.ap and WSI.da), which is especially noticeable when analyzing them with respect to rainfall (Appendix A). The dispersion of WSI values is higher in small watersheds with low water availability (Appendix A). There are 40 studied watersheds with a WSI greater than 40%, which on average had an anthropization index of 0.415, while 90 watersheds had a WSI of less than 20% and an average anthropization index of 0.312, which indicates a relationship between these two indices.

When grouping the watersheds that supply drinking water systems into macro-basins, high variability is observed in the average WSI.da in the Bueno, Aysén, and Baker macro-basins, in addition to relatively high values in individual watersheds in Chiloé (Figure 4). WSI.ap values are generally low, with the exception of the drinking water systems that supply Villa O’Higgins and the city of Punta Arenas, with values above 40%.

Finally, if we consider the drinking water systems with surface sources and the highest number of users, there are six APU water intakes (three small ones of Coyhaique, Punta Arenas, Ancud, and Puerto Ibañez; 222,760 people) with moderate/high WSI.ap (>25%), six APU water intakes (two small ones of Coyhaique, Quemchi, Rio Negro, Osorno, and Puerto Ibañez; 226,694 people) with high WSI.da (>35%), and nine APU water intakes (three small ones of Coyhaique, Quemchi, Rio Negro, Punta Arenas, Puerto Ibañez, Osorno, and Ancud) with high WSI (>30%). Of the 10 water intakes of APR systems with surface sources and the most users (>2000 people), 6 water intakes (2 of Mañihuales, Maicolpue, Queilen, Llau Llao, and Nercon/Los Aromos/Gamboa Alto; 183,250 people) have moderate/high WSI.da (>30%), 1 APR intake (Pid Pid) has moderate/high WSI.ap (36%) and 7 APR water intakes (2 of Mañihuales, Maicolpue, Queilen, Pid Pid, Llau Llao and Nercon/Los Aromos/Gamboa Alto) have high WSI values (>30%).

3.3. Social Perceptions

Of the 333 APR systems in the database, leadership contacts were successfully reached for 135 systems (40.5%), of which 117 completed surveys and 18 declined participation, yielding a response rate of 86.7% among contacted systems. The regional distribution of completed surveys reflected the database composition, with 98 responses from Los Lagos (83.8%), 16 from Aysén (13.7%), and 3 from Magallanes (2.6%). Water source types were evenly distributed between surface water and groundwater systems. Geographically, the sample encompassed the diverse topography of western Patagonian landscapes: coastal islands and interior fjord channels (56.4%), mountainous areas (22.7%), and central valleys (20.9%).

The majority of participants (77.8%) served as presidents of their respective water system directorates, with additional representation from secretaries (11.1%) and a combined 11.1% comprising treasurers, operators, and municipal representatives. System operational history varied considerably: 44.6% had been functioning for 15 years or less, 25% for 16–25 years, and 30.4% for 26–65 years. Concerning water rights registration, 59.8% of participants confirmed their systems possessed formally inscribed water use rights, while 16.2% indicated their rights remained unregistered, and 23.9% were unsure of their registration status.

3.3.1. Governance Priority Differences

No statistically significant differences in governance priorities were observed between surface water and groundwater systems or based on length of system operation; however, significant geographic differences were identified when comparing geographic zones: coastal, valley, and mountain systems (

Table 3. Summary of significant landforms governance priority differences for geographic zones: coastal, valley, and mountain systems.

Variable	Comparison Type	Test	p-Value	Effect Size	Croup Means	Post Hoc Comparisons
User participation	Geography	Kruskal–Wallis	0.006 **	η2 = 0.089	Mountain: 8.95	Coastal > Valley * Mountain > Valley *
					Coastal: 8.77
					Valley: 8.39
Regulatory compliance	Geography	Kruskal–Wallis	0.009 **	η2 = 0.083	Coastal: 8.62	Coastal > Mountain *
					Valley: 8.29
					Mountain: 8.09
Infrastructure priority	Geography	Kruskal–Wallis	0.025 *	η2 = 0.064	Coastal: 8.86 Mountain: 8.86	Coastal > Valley *
					Valley: 8.29
Water quality monitoring	Geography	Kruskal–Wallis	0.017 *	η2 = 0.072	Coastal: 8.66 Mountain: 8.55 Valley: 8.29	Coastal > Valley * Mountain > Valley *

Notes. The scale used was 1 = completely unimportant, 2 = very unimportant, 3 = unimportant, 4 = somewhat unimportant, 5 = neutral, 6 = somewhat important, 7 = important, 8 = very important, 9 = completely important. ** p < 0.01, * p < 0.05. Post hoc comparisons with Bonferroni correction shown were significant. Effect sizes: η² = eta-squared (small ≥ 0.01, medium ≥ 0.06, large ≥ 0.14). All effect sizes represent medium effects by social science standards.

).

Geographic location significantly influenced governance priorities across multiple domains (Figure 5). Mountain zones assigned the highest importance to user participation (8.95), followed by coastal (8.77) and valley zones (8.39; Kruskal–Wallis H, p = 0.006, η² = 0.089). Post hoc Dunn’s pairwise comparisons with Bonferroni adjustment indicated that both coastal and mountain zones ranked user participation significantly higher than valleys. Coastal zones placed the greatest emphasis on regulatory compliance (8.62), compared to valley (8.29) and mountain zones (8.09; p = 0.009, η² = 0.083), with Dunn’s test revealing a significant coastal–mountain difference. For water quality monitoring, priorities were highest in coastal (8.66) and mountain zones (8.55) and lowest in valleys (8.29; p = 0.017, η² = 0.072), with coastal zones significantly exceeding valleys. Infrastructure priority displayed a U-shaped pattern, with coastal and mountain zones equally high (8.86) and valleys again lower (8.29; p = 0.025, η² = 0.064), with Dunn’s test confirming both coastal–valley and mountain–valley differences. Across all four domains, valley zones consistently scored lowest, indicating a persistent “valley governance gap.”

Effect sizes were moderate by social science standards, and the consistent pattern suggests that environmental context systematically shapes APR management priorities in Chilean Patagonia. No significant differences in governance priorities were observed by water source type or system age. Additional context can be gleaned through a review of the qualitative comments provided by governance committee representatives (see Appendix B).

3.3.2. Correlation Analysis

The correlation analysis revealed distinct patterns in the relationships between watershed conditions and governance priorities among rural water system leaders (

Table 4. Pearson correlation matrix: watershed conditions and governance priority perceptions.

	Infrastructure	Monitoring_SYS	Regulations	User_Part	Techcapacity	Finan_Resour	AI	WSI
Infrastructure	1.000	0.340 *	0.008	0.287 *	0.144	0.231 †	−0.008	0.043
Monitoring_SYS	0.340	1.000	0.718 *	0.060	0.034	−0.060	0.017	0.047
Regulations	0.008	0.718	1.000	−0.058	0.078	0.114	0.172	0.060
User_Part	0.287	0.060	−0.058	1.000	0.154	0.177	−0.064	−0.308 *
Techcapacity	0.144	0.034	0.078	0.154	1.000	0.078	−0.057	−0.284 *
Finan_Resour	0.231	−0.060	0.114	0.177	0.078	1.000	0.099	0.029
AI	−0.008	0.017	0.172	−0.064	−0.057	0.099	1.000	0.353 **
WSI	0.043	0.047	0.060	−0.308	−0.284	0.029	0.353	1.000

** p-value < 0.01; * p-value <0.05; † p-value < 0.10.

). The WSI demonstrated significant inverse correlations with both technical capacity (r = −0.284, p < 0.05) and user participation (r = −0.308, p < 0.05), indicating that leaders of water systems experiencing greater water stress are more likely to emphasize technical capacity building and user participation, a finding supported by both theoretical frameworks and empirical studies, which show that lower water security encourages stakeholders to adopt adaptive, participatory strategies.

Conversely, AI showed no significant correlations with any governance priority variables, suggesting that anthropological impact levels do not directly influence how system leaders prioritize different governance aspects. The lack of significant correlation between AI and governance priorities further suggests that cumulative human impacts do not directly shape governance perceptions; rather, decision-makers respond predominantly to immediate risks and system vulnerabilities reflected in water security metrics, not broader anthropogenic pressures.

Finally, the positive and significant correlation between the AI and WSI (r = 0.353, p < 0.01) confirms that greater anthropogenic impact leads to elevated water demand or watershed degradation, resulting in increased water stress, a relationship widely substantiated in the eco-hydrological literature.

Among governance priorities, significant positive correlations emerged between infrastructure and monitoring systems (r = 0.340, p < 0.05), infrastructure and user participation (r = 0.287, p < 0.05), and monitoring systems and regulations (r = 0.718, p < 0.05). These relationships suggest clustering of governance priorities, with leaders who value one aspect of system improvement often valuing related aspects. Financial resources showed a marginally significant correlation with infrastructure (r = 0.231, p < 0.10), indicating a trend toward recognizing the interconnection between financial resources and infrastructure development.

4. Discussion

4.1. The Biophysical Dimension of Water Security in Chilean Patagonia

4.1.1. Watershed Characterization

The morphometry of the studied watersheds matches the characteristics of mountain watersheds, with small areas, relatively short distances, and moderate elevation differences. In this type of watershed, vegetation cover plays a relatively important role in hydrological flow [29,30,31,32], since the different types of vegetation significantly influence soil water storage [32] and, therefore, water residence time in the watershed. Native forest cover is able to intercept and store water more effectively than other types of land cover, reducing surface runoff [31,32], while land covers such as shrublands and grasslands have a lower interception rate and a lower soil water storage capacity [30,31,32]. Therefore, the percentage of native forest cover and the anthropization index are two relevant elements to consider, and are also strongly related to WSI values.

4.1.2. Water Stress

The WSI is a useful indicator of water stress in watersheds that supply drinking water. By conducting separate analyses of actual water use (WSI.ap) and potential water use (WSI.da), we were able to analyze current pressures but also project scenarios where all WURs granted by the State are effectively used (WSI). This allows us to categorize the current level of water stress in watersheds and anticipate potential problems arising from an excessive allocation of WURs.

Traditional interventions by the Chilean State have generally addressed scarcity problems at the local scale, without considering the watershed concept [22,34]. Conducting the analysis at the watershed scale is key to addressing problems systemically [36], through tools such as Integrated Watershed Management (IWM [2]). First, IWM provides a framework for different institutions related to water management policies, principles, and practices so that they can support management actions [2,36]. Second, it serves as a sequence of steps toward solutions to a variety of different types of water-related problems [2], which depend on the conservation status of the watersheds, productive practices, and behaviors of users and inhabitants.

As expected, there was a very low percentage of watersheds with high WSI.ap (6%) in higher precipitation conditions (Table 2). However, this situation can change drastically during droughts, nearly doubling the number of watersheds with a high WSI.ap (Figure 2 and Table 2). Thus, although interannual climate variability in southern Chile is lower than in central and northern regions of Chile [41], drier-than-normal years or seasons, typically observed under El Niño events and/or positive phases of the Southern Annular Mode (SAM), may clearly threaten water supply. Note that the extreme conditions of 2016 were a consequence of a strong El Niño phase combined with the SAM, producing an all-time low streamflow.

If we consider WURs, the percentage of watersheds with a high WSI is clearly higher (26.5%, Table 2) and can exceed 34% (Table 2) under drought conditions. Considering that climate projections foresee rainfall decline, and an increase in the frequency of drought events across the study area [54,55,56,57], it becomes important to implement frameworks such as IWM [2] to reduce the risks of poor water storage capacity and decreasing water quality.

It is also important to note that WSI.ap does not account for water uses beyond the agricultural and drinking water sectors, which generally dominate consumptive uses in southern Chile [22]. In a rural region in the incipient phase of development, where irrigation and canal systems are virtually nonexistent, and rural development is relatively stable, urban and rural water supplies are roughly balanced, while agricultural use is negligible. However, other uses, such as those from manufacturing industries and livestock activities, can contribute significantly in certain watersheds, particularly those that include larger urban areas such as Osorno.

When analyzing the results based on geoforms and large watersheds, we observed that the northern sector of the study area and the trans-Andean valleys are the areas with the greatest water stress, which is related to the precipitation and land cover. Furthermore, it is important to highlight that there is high variability in the studied watersheds, and in many cases, we observed isolated cases with high levels of water stress, particularly in small-scale watersheds or those located in the coastal area (Figure 3). This suggests that generalizing on the state of drinking water sources in western Chilean Patagonia is not justified, and it highlights the importance of implementing protection and restoration measures at watershed scale [2,29,30,31,35,36], especially for those that experience high levels of anthropization and water stress. This is particularly relevant considering that the vast majority of drinking water systems do not have alternative water sources.

4.1.3. Current and Future Scenarios of Water Sources

Groundwater management and governance face challenges specific to the nature of this resource, as it is hidden from sight, and difficult to assess/map in terms of amount, accessibility, quality, renewability, among others [17]. In this study, we did not consider groundwater sources because there are no hydrogeological maps indicating the sources from which water is obtained for 51.6% of the drinking water systems. This is clearly a limitation to fully understanding water security in western Patagonia.

Although comparing surface water and groundwater sources is challenging from a water security perspective, some general patterns and potential trends are worth noting. First, groundwater sources in Chilean Patagonia are mostly located in northern latitudes, where population density is significantly higher, and the colonization and development period was much more prolonged (>400 years for the Lakes Region in Chiloe, <100 years for the intermediate latitudes of the Aysen Region, and <200 years for the southern Magellan regions (see [54] for a historical review of land use in the region)). Presumably the proportion of surface to groundwater sources is influenced by time, and the corresponding economic development, population growth, demand, and increased potential for investment in subsurface water sources. Shift to groundwater sources may also be a response to decreasing alternatives, with a decline in the yield or quality of surface waters, especially in the lower elevations of the central valley and coastal landforms, where drainage densities may also be limited. This suggests that demand for groundwater sources might be expected to increase over time, especially under the recent trajectories of decreased precipitation (affecting < 40° S to 46° S) and expected climate change scenarios showing further declines (but transitioning to projected increase south of 48° S) and increased temperatures in the cordillera throughout the region [33,55,56,57].

In this context, groundwater would be expected to supply a more secure source and represent an increasing proportion of water capture points, as development advances south of 42° S. However, this highlights additional challenges in terms of water supply planning and the relationship to water security and economic development. There are a number of lessons across cases relating to four elements of groundwater governance: an institutional setting, access to science and information, the robustness of civil society, and economic and regulatory frameworks [17].

We may find ourselves trading surface water sources, which are more vulnerable but also more readily characterized and managed from a watershed perspective, for groundwater sources. These, in turn, may be more secure in the short term, but they are nevertheless vulnerable in the long term, as land use shifts towards urbanization. Meanwhile, they are essentially black box systems, making watershed management much more complicated (e.g., “day zero scenario” [58]), and demanding costly hydrogeological studies with greater uncertainty. In this long-term scenario, perhaps exemplified by the city of Coyhaique (45° S, >50,000 people), currently supplied by four surface water intakes (three of them with a high WSI), contamination or overexploitation of potential groundwater sources in an expanding urban footprint may be essentially irreversible and irrecoverable. This long-term tradeoff in water resource management plays out over the increasingly narrowing opportunities of managing urban expansion and climate stress.

4.2. The Social Dimensions of Water Security in Chilean Patagonia

Our social analysis reveals a fundamental paradox that reinforces the central idea of a “mirage of drinking water security” in Chilean Patagonia. While 63.3% of APR leaders rated their water quality as “excellent” and 42.3% considered their systems “absolutely secure,” the marked differences in governance priority we identified suggest underlying vulnerabilities that challenge this apparent confidence. This gap between perceived security and persistent governance concerns illustrates how the region’s water abundance may indeed create a deceptive sense of security that masks critical structural challenges.

4.2.1. Geographic and Water Security Influences on Governance Priorities

No significant differences were observed between surface water and groundwater systems or based on system operational age; however, significant geographic differences emerged across coastal, valley, and mountain zones. This pattern suggests that environmental context, rather than technical system characteristics or operational experience, drives governance priority differences. The significant differences in governance priorities across geographic zones demonstrate that environmental context systematically shapes water management approaches in ways that extend beyond simple resource availability. This finding directly addresses our second research objective regarding leaders’ perceptions of governance challenges, revealing that topographic position fundamentally influences management priorities, even in a region of apparent abundance.

The geographic patterns we identified—particularly the “valley governance differential”, where valley systems consistently showed lower governance priorities—suggest that topographic position within watersheds influences both vulnerability perceptions and management capacity. Mountain zones’ emphasis on user participation (8.95 vs. 8.39 in valleys, p = 0.006) may reflect greater community self-reliance necessitated by geographic isolation, while coastal zones’ focus on regulatory compliance (8.62 vs. 8.09 in mountains, p = 0.009) could indicate different regulatory pressures or infrastructure standards in more accessible areas.

With respect to the 54 surface APR systems for which both biophysical and perceptual data were available, the absence of significant correlations between the AI and governance priority perceptions suggests an important disconnect in rural water governance in Chilean Patagonia. Despite varying levels of human activity within watersheds, system leaders’ priorities for governance improvements appear to be driven by factors other than the actual land use conditions of their water sources. This finding aligns with broader research on Chilean rural water governance, which suggests that local water management decisions are often influenced more by institutional frameworks and immediate operational challenges than by comprehensive watershed assessments [59,60]. The disconnect may reflect limited awareness among APR leaders about watershed-scale land use impacts, or alternatively, that governance priorities are shaped primarily by day-to-day operational experiences rather than broader environmental conditions.

The significant inverse correlations between the WSI and both technical capacity and user participation priorities provide crucial insights into how water security concerns manifest in governance preferences. Communities experiencing lower water security (higher stress) prioritize technical capacity building and enhanced user participation, suggesting that water stress drives recognition of the need for more sophisticated management approaches and greater community engagement. This pattern reflects findings from other Chilean studies demonstrating that water scarcity catalyzes collective action and institutional strengthening in rural communities [61]. The emphasis on user participation during water stress periods aligns with Ostrom’s principles of common pool resource governance, where resource scarcity often enhances the perceived value of collective decision-making and monitoring mechanisms [12,62]. This pattern is particularly relevant in the context of Chilean rural water systems, where community-based management through APRs has been identified as essential for effective water governance, especially during periods of resource stress [63,64].

The clustering of governance priorities, particularly the strong correlation between monitoring systems and regulations (r = 0.718), indicates that APR leaders recognize the interconnected nature of effective water governance. This systemic understanding suggests that successful water management requires coordinated attention to multiple governance dimensions simultaneously. The pattern aligns with network governance theory, which emphasizes that effective rural water management emerges from integrated approaches rather than isolated interventions [64]. The correlation between infrastructure and user participation priorities further supports this perspective, suggesting that leaders understand that physical system improvements must be accompanied by social and institutional development to achieve sustainable outcomes.

These findings have important implications for water governance policy and capacity-building programs in Chilean Patagonia. The lack of correlation between actual watershed conditions and governance priorities suggests that APR leaders may benefit from training programs that enhance their understanding of watershed-scale processes and their implications for long-term system sustainability. Additionally, the strong relationship between water security concerns and preferences for technical capacity and user participation indicates that support programs should be designed to respond dynamically to varying levels of water stress, with more intensive capacity-building efforts directed toward communities experiencing greater water security challenges.

4.2.2. Climate Change and Monitoring Priorities

The higher prioritization of water quality monitoring among surface water systems (p = 0.007) takes on greater significance when considered alongside documented climate vulnerabilities in the region. Synergistic effects of climate change, land use change, and increasing contamination pressures have been identified [25,26,27,33] that particularly threaten surface water sources. Our findings suggest that APR leaders managing surface water systems may be intuitively responding to these documented vulnerabilities by prioritizing monitoring infrastructure, even in the absence of regulatory mandates. This governance response becomes particularly important given that current APR systems “do not monitor flow rates (water quantity), and quality analysis is performed infrequently,” creating critical information gaps precisely where climate impacts are expected to be most severe.

To complement the temporal and spatial analyses, it would be of interest to study a small number of human–water systems in more detail, including routine monitoring, to gain more detailed insights into causal relationships. This may involve detailed data collection of the hydrological and sociological processes involved, including real-time learning, to understand human–water system functions in the present to be able to predict possible trajectories in the future [10].

4.2.3. Water Rights System and Governance Adaptation

The systematic governance priority differences we identified reflect broader structural challenges in Chile’s water management framework. Water rights calculations rely on historical flow records, without considering climate projections or hydrological seasonality [34], precisely the uncertainties that may drive surface water systems to prioritize regulatory compliance more highly than groundwater systems (p = 0.027). The geographic governance differential we observed, particularly the lower priorities in valley zones, may reflect the complex governance challenges [28], where APR managers must navigate water security without controlling upstream watershed activities. This disconnect between management responsibility and territorial control appears to manifest differently across geographic contexts, potentially explaining the topographic patterns in governance priorities that we documented.

4.2.4. Watershed Vulnerability and Governance Response

The surface water systems’ higher regulatory compliance priorities directly address the watershed management challenges documented [26,27,28,33,34,35], which demonstrate how upstream land use activities affect downstream water quality. Specifically, threats to mountain watershed sources in southern Chile are identified [33], precisely the context in which we found heightened governance priorities for both monitoring and user participation. Given the differing interests and emerging pressures related to water, ensuring water security requires well-resourced public sector agencies to coordinate interaction across sectors and actors [16].

The governance patterns we identified suggest that APR leaders are developing institutional responses to the fundamental challenge we outlined in our introduction: managing water security without owning or controlling the watersheds that supply their systems. The geographic governance differential may reflect varying degrees of watershed vulnerability and upstream pressure across different topographic contexts.

4.2.5. Regional Context and Infrastructure Gaps

Despite Chile’s water systems being considered “a benchmark in Latin America”, with the highest coverage rates [23,24], our social findings reveal governance adaptations that suggest underlying system stress. Despite high confidence ratings, participants’ qualitative responses revealed significant concerns about aging infrastructure, capacity limitations, and electrical dependencies. The fact that 44.4% of systems rely on water tank trucks as backup supply options, and 11.1% have no alternatives at all, suggests that the apparent security is more fragile than initial perceptions indicate, aligning with the broader regional challenges identified [27,33] regarding increasing development pressures in Patagonia. This fragility becomes particularly concerning when considered alongside the land use pressures and climate change impacts discussed in our introduction. The governance priority differences we documented may represent early institutional responses to these mounting pressures, occurring even within a context of apparent water abundance and high system coverage rates.

5. Conclusions

This research provides information that has not been previously systematized and integrates eco-hydrological and social variables that allow for a more comprehensive understanding of the current situation of drinking water systems in western Chilean Patagonia. We identified 334 drinking water intakes in western Chilean Patagonia, of which 309 (90%) correspond to APR systems serving 232,279 people and 34 (10%) are APU systems serving 614,071 people. Of these intakes, 51.6% (165 APR and 12 APU) draw from groundwater sources, while 45.8% (136 APR and 21 APU) rely on surface water (streams and rivers). However, there are significant information gaps that must be addressed immediately, such as quantity and quality monitoring of surface watercourses, and hydrogeological studies to quantify and map groundwater sources. This makes it necessary to implement hydroclimatic monitoring of APU and APR systems, where there is an opportunity to include highly socially relevant systems in an existing state managed network (DGA).

Although a small proportion (26.5%) of drinking water systems currently have a high WSI, it is important to note that this situation could change drastically with the current WURs allocation system and climate change projections. Therefore, it is imperative to take political/legislative measures to protect these watersheds from the over-allocation of WURs and to begin a land use planning process to protect and restore the watersheds that supply drinking water.

Analysis of 117 APR systems across Chilean Patagonia reveals significant geographic differences in governance priorities, with valley systems consistently showing lower priorities across all domains compared to coastal and mountain zones, creating a distinct “valley governance gap.” Among the 54 surface water systems with complete biophysical data, water security stress, rather than the AI (reflecting land use), drives governance priorities, with water-stressed communities emphasizing technical capacity (r = −0.284) and user participation (r = −0.308), while no correlations emerged between actual watershed conditions and management priorities. The strong clustering of governance priorities, particularly between monitoring and regulations (r = 0.718), indicates that leaders recognize the interconnected nature of effective water management. These findings highlight the need for geographically targeted capacity-building approaches that address the valley governance differential and include watershed education programs, to bridge the disconnect between environmental conditions and management focus.

The future research directions involve expanding beyond APR systems committees’ leaders’ perspectives. Our study provides critical insights into APR governance priorities, yet this represents only one dimension of the complex social–ecological dynamics affecting water security in Chilean Patagonia. Future research should adopt a more holistic approach that integrates perceptions across the full spectrum of watershed stakeholders. This includes not only APR users—who experience the direct outcomes of governance decisions—but also non-users who consume water at various points along the watershed continuum, both upstream and downstream of APR and APU intake points. Understanding how different stakeholder positions within the watershed influence water security perceptions could reveal important disconnects between governance priorities and broader community needs, particularly given that APR managers lack control over upstream activities that directly affect their water sources. We need to understand stakeholders’ current level of knowledge and actions on watersheds, which can inform targeted education and capacity-building programs to improve adaptive water governance.