Current Issues and Challenges in Slovak Water Reservoir Management

Abstract

Water reservoirs are an important source of drinking water in Slovakia and are managed under the control of regional water utility enterprises. These enterprises face increasing challenges due to ecological pressures, land use conflicts, and technological constraints. This paper investigates the external factors that influence the management of drinking water reservoirs and their implications for water quality. Using the PESTLE framework (Political, Economic, Social, Technological, Legal, and Environmental), we analyse case studies from four Slovak reservoirs: Málinec, Turček, Nová Bystrica, and Hriňová. The data was collected in 2025 using structured interviews with representatives of four water management enterprises and forest managers (three respondents from Málinec, Turček and Hriňová, two respondents from Nová Bystrica), whose forests surround the chosen water reservoirs. The analysis reveals that forest management, stakeholder relations, extreme climate events, and outdated infrastructure significantly affect water treatment efficiency and operational costs. While national water policy provides a uniform regulatory framework, the case studies demonstrate that local conditions and governance dynamics strongly impacts the water management utilities and its performance in drinking water treatment.

1. Introduction

Water, as a strategic resource, plays a crucial role not only in meeting the basic needs of the population but also in driving economic development, protecting ecosystems, and facilitating adaptation to climate change [1]. At the European scale, water bodies are subject to multiple pressures, including diffuse agricultural pollution, hydromorphological alterations, and climate change impacts. According to the European Environment Agency, only 40% of surface water bodies in the EU achieve good ecological status or potential under the Water Framework Directive, with agriculture identified as the most significant pressure, affecting 22% of the total area of surface waters [2]. In southern Europe, water scarcity affects up to 30% of the population on an annual basis, with severe seasonal shortages during summer months [3]. Despite these pressures, more than 97% of the EU population has access to improved drinking water sources, although disparities remain between urban and rural areas [4].

In the European context, most of the population is supplied through public water supply systems, which are subject to strictly regulated EU legislation. According to Council Directive 98/83/EC [5] on the quality of water intended for human consumption, the quality of drinking water must be continuously monitored to ensure compliance with all required standards. However, in the case of smaller sources (e.g., private wells), oversight of water quality often remains the responsibility of the owners themselves, resulting in significant differences in monitoring and water quality across regions.

Water quality is influenced by a variety of natural and anthropogenic factors—ranging from geological and hydrological processes to the composition of land cover. Extensive scientific literature confirms that land use and land cover (LULC) changes have a direct impact on water quality in streams [6,7,8]. The transformation of natural habitats into agricultural land or built-up areas has significantly improved human comfort and well-being, but at the cost of degrading ecosystem services and biodiversity [9]. Forests and wetlands serve as important buffers that capture diffuse pollution [10,11], while urbanised and agricultural areas contribute to higher inputs of nutrients and foreign substances. Forests also reduce runoff, promote infiltration, and decrease erosion, thereby helping to reduce turbidity and sediment enrichment of water bodies [12,13].

The Slovak Republic is characterised by an abundance of water resources, which are crucial for ensuring the supply of drinking water to the population. In Slovakia, 82.2% of drinking water is sourced from groundwater and 17.8% from surface water [14]. Groundwater, especially from the Žitný ostrov region, is considered the highest quality source of drinking water in the country. Surface water sources, such as reservoirs and streams, play an important role, particularly in areas where high-quality groundwater is not available. Almost all drinking water from surface sources is connected to forest ecosystems, reflecting the fact that all large water reservoirs (WRs) in Slovakia (WR Turček, Málinec, Hriňová, Klenovec, Starina, Nová Bystrica, Klenovec) are in forested areas. Surface sources of drinking water—particularly drinking water reservoirs—are especially sensitive to impacts from their catchments. Agricultural activity, forestry, and dispersed settlements influence the quality of raw water and thus increase the need for technological treatment. In this context, the importance of effective management of water protection zones and the promotion of nature-based land use practices is increasing [15].

Water quality and its protection are closely linked to landscape management in the vicinity of drinking water reservoirs. Research by Trenčiansky et al. [16] demonstrated that a change in land management practices—from intensive agricultural production to ecological farming without fertilisers and chemicals, followed by natural overgrowth of the catchment with trees and shrubs—led to a marked improvement in runoff water quality parameters. This 36-year monitoring confirms that landscape management has a direct impact on the quality of water in reservoirs and should be an integral part of water supply policy.

In addition to the environmental aspect, attention must also be paid to the structure and functioning of water supply companies themselves. These companies are characterised by their dependence on the external environment—technological availability, environmental conditions, and social pressures. Unlike conventional enterprises, these organisations cannot fully apply standard strategic planning tools. Their managerial decision-making is influenced by numerous external factors, including legislative requirements, technical and environmental constraints, public opinion, and available natural resources. Given their social responsibility and fundamental importance for public health and safety, they face specific challenges that require tailored managerial approaches [17].

Therefore, it is crucial to analyse not only internal processes but especially external factors that represent either opportunities or threats to the effective management of these entities. The literature identifies several frameworks for analysing these factors—the most common include the PESTLE framework (political, economic, social, technological, legislative, and environmental factors) [18], as well as the DPSIR framework (Driving forces-Pressures-States-Impacts-Responses), commonly used in environmental analyses [19].

It is also relevant in this context to reassess foreign experiences. For instance, a study conducted in southern Italy [17] identified the main barriers and enabling factors for the development of water recycling from the perspective of water utilities. The study also confirmed that the contextual conditions—geographical, legislative, and social—significantly influence the success of innovation implementation and operational efficiency.

In contrast, research from Canada [20] points to the growing need for an integrated approach to risk management in urban water supply systems. As part of a project at the University of Guelph, the Water Utility Risk Integration Matrix (WURIM) was developed [21], classifying the main sources of risk as climate change, urbanisation, and ageing infrastructure. The case of Singapore demonstrates that a combination of alternative water sources, strict monitoring, and demand management can achieve a high level of water self-sufficiency even in challenging conditions [22]. Literature also indicates that drinking water systems currently have the most detailed risk management frameworks, often based on the HACCP methodology [23], which identifies and eliminates hazards from the source to the end user.

On the other hand, most European literature tends to focus on only selected aspects (e.g., hydrological, social, or legislative) without providing a comprehensive view of the entire value chain [17]. In the Central European context, research on drinking water reservoirs has predominantly addressed either physicochemical monitoring (e.g., nutrient loads, sediment contamination) or compliance with the EU Drinking Water Directive, without systematically linking these aspects to broader socio-economic, technological, environmental, and political factors. Moreover, comparative studies assessing multiple reservoirs within a single legislative and geographical framework are scarce, which limits the ability to identify patterns, shared challenges, and transferable management strategies.

For this reason, the main objective of this paper is to identify the key external factors that impact the management of water utilities in Slovakia regarding to preservation of water quality. Based on a qualitative analysis of case studies from four drinking water reservoirs (Turček, Nová Bystrica, Hriňová, Málinec), we identify the main influential factors arising from their specific external environment: social and cultural, political and legislative, economic, environmental, and technical. Such insight is essential for developing effective adaptation strategies and management practices in enterprises responsible for drinking water treatment in Slovakia, particularly in the context of climate variability, evolving legislative frameworks, and complex land management systems.

2. Materials and Methods

2.1. Case Studies

The Slovak drinking water supply system is composed of 14 water companies, with prices varying based on the decisions of the Regulatory Office for Network Industries (ÚRSO) [24]. For example, the drinking water reservoirs Starina, Nová Bystrica, and Hriňová supply water to residents of eastern, northern, and central Slovakia [25]. The price of water in the Slovak Republic has increased nearly fortyfold between 1989 and 2024 [26]. Household water consumption has been on a downward trend—from 195 L per person per day in 1990 to approximately 80 L today [27]. In 2023, approximately 90.5% of the Slovak population was supplied with water from public water systems, while 9.5% relied on individual sources such as private wells, which often fail to meet hygiene standards [28]. Water body management in Slovakia is governed by the Water Framework Directive 2000/60/EC [29], but faces challenges related to fragmented land administration, insufficient intersectoral coordination, and varying levels of implementation of measures across catchments [30].

The four case studies (CS) in a single-country context [31] were carried out in four water reservoirs (WR): WR Turček, WR Málinec, WR Hriňová, WR Nová Bystrica (Figure 1). The aim was to identify the specific external conditions influencing the management of each reservoir. The investigated reservoirs were chosen to represent the water management sector in Slovakia. As part of the scientific projects, these reservoirs covers basic types of the reservoirs in Slovakia related to (i) volume of the reservoirs (two reservoirs belongs to biggest in Slovakia; two small reservoirs); (ii) altitude (representative selection from highest to lowest altitude); (iii) different forest cover (representative selection from highest to lowest forest cover and (iv) different ages of water treatment plants (representative selection from oldest to youngest technology).

Understanding the specifications of each water reservoir management helps to identify emerging external factors affecting the broader water utility sector.

The investigated water reservoirs are all located in Central Slovakia. The water reservoirs differ in basic characteristics such as volume, altitude, water treatment costs, etc. (

Table 1. Study site characteristics.

Characteristics/Water Reservoir		Málinec	Turček	Nová Bystrica	Hriňová
First operation year		1994	1999	1989	1965
Catchment		Ipeľ	Váh	Váh	Hron
Altitude	[m.a.s.]	345	777	599	565
Reservoir volume	[mil.m3]	26.7	10.6	32.8	7.38
Average water consumption 1	[mil.m3·year−1]	2.6	3.64	7.05	3.93
Water surface of the area	[km2]	1.38	0.54	1.81	0.56
Catchment area	[km2]	83.13	29.32	29.02	72.41
Forest cover in the catchment	[%]	57.47	97.13	73.12	86.92
Average costs for drinking water treatment	[€.thous. m−3·year−1]	11.79	14.98	8.73	19.43
Costs for water treatment Max 1	[€.thous. m−3·year−1	13.6	23.7	12.62	8.88
Costs for water treatment Min 1	[€.thous. m−3·year−1]	7.8	7.6	5.26	24.80
Standard deviation		1.38	6.04	2.13	4.59
Reservoir height	[m]	48	59	57	42
Number of consumers	[thousands]	63	89	170	95
Water treatment facility volume	[L·s−1]	280	120	700	125
Maximum water treatment facility volume	[L·s−1]	560	250	1050	260

Note(s): ¹ Value calculated based on the time series 2010–2022.

). This variability of chosen reservoirs covers operating conditions of water reservoirs and allows us to identify an applicable scope of PESTLE factors that influence strategic decisions regarding ensuring drinking water quality in Slovakia.

2.2. Structured Interviews

The management of water reservoirs in the study area is under the authority of a Slovak water management company, a state-owned enterprise, Bratislava, Slovakia, which has directors and management units at each water reservoir. They are responsible for the operation, maintenance, and protection of the reservoirs and therefore represent the most important actors in the decision-making process. Accordingly, structured interviews were conducted with representatives of water management enterprises to analyse drinking water treatment and the external factors affecting this process (

Table 2. List of the interviewees.

ID	WR	Respondent
M1	WR Málinec	Technological director of the water management unit Málinec, specialist)
M2	WR Málinec	Director of the water treatment unit Málinec
M3	WR Málinec	Director of LS Poltár (branch of the LESY, state forest enterprise, Bánská Bystrica, Slovakia)
T1	WR Turček	Technological director of the water management unit Turček (specialist)
T2	WR Turček	Technologist of the water management unit Turček (specialist)
T3	WR Turček	Director of Kremnica, the municipal forest enterprise, Kremnica, Slovakia
NB1	WR Nová Bystrica	Employee of the water management unit Nová Bystrica (specialist)
NB2	WR Nová Bystrica	Employee of the Lesy, state forest enterprise
H1	WR Hriňová	Employee of the water management unit Hriňová (specialist)
H2	WR Hriňová	Director of LS Poľana (branch of the LESY, state forest enterprise)
H3	WR Hriňová	Employee of the water management unit Hriňová (specialist)

). Given the strong evidence that forests and forest management influence both the quality and quantity of drinking water [10,11,12,13], managers of forest enterprises operating in the catchments were also interviewed, as their activities have a direct impact on water resources. End users/consumers and private water supply companies were not included in the interviews, as the study focused on entities directly involved in the management, protection, and operational decision-making related to drinking water reservoirs.

2.3. The PESTLE Analysis

The PEST analysis is a commonly used method for examining the external environment of the organisation. The acronym stands for Political, Economic, Social and Technological factors that influence the organisation and must be considered in strategic planning [32]. The PESTLE strategic analysis builds on the PEST concept and includes two other sets of factors—Environmental and Legislative. The analysis provides a general overview of an organisation’s macro-environment and delivers the strategic and managerial information on a qualitative basis [33]. The PESTLE is widely used in sectors related to the management of renewable and non-renewable resources, since strategic decision-making about their use is mainly based on external factors [34,35,36,37] and was used to identify unavoidable external changes in water management in Slovakia. Based on the review of relevant literature, strategic documents, national legislation and interviews with stakeholders, we developed a specific set of external PESTLE factors (

Table 3. Specific PESTLE factors and its operationalisation.

Group 1	Factor	Criteria	Effect 2
P	Strategic documents on European level	Yes exist/No	P/Nt/Ng
	Strategic documents on National level	Yes exist/No	P/Nt/Ng
	Strategic documents on Regional level	Yes exist/No	P/Nt/Ng
	Strategic management decision	Top-Down/Bottom-Up	P/Nt/Ng
	Cross-sectoral coordination	Yes/No (one sector/two sectors/more than two sectors)	P/Nt/Ng
E	Demand (ratio of annually treated drinking water to reservoir volume—compared to other involved WR)	Low < 20/Moderate 20–50/High > 50 3	P/Nt/Ng
	Supply (volume of reservoir—compared to other involved WR)	Low < 10/Moderate 10–25/High > 25 3	P/Nt/Ng
	Price (costs for water treatment—variability of costs in period 2010–2022—compared to other involved WR; costs for water treatment = Costs for purchasing chemicals used to treat raw water)	Low < 10/Moderate 10–15/High > 15 3	P/Nt/Ng
S	Relationships between water management utility and agro-forest stakeholders	Conflict/neutral/consensual [stakeholder groups involved]	P/Nt/Ng
	Recreation	Yes/No	P/Nt/Ng
T	Available water treatment technology	Description [narrative]	P/Nt/Ng
	Outdated, unsuitable water treatment technology	Yes/No	P/Nt/Ng
	Water collection method	Yes/No	P/Nt/Ng
	Technological problems in water treatment	Yes/No	P/Nt/Ng
	Hydroelectric power plant	Yes/No	P/Nt/Ng
L	Water protection restrictions	Yes/No	P/Nt/Ng
	Environmental restrictions protection	Yes/No	P/Nt/Ng
	Forest protection restrictions	Yes/No	P/Nt/Ng
	Agricultural protection restrictions	BAU/Differential Forest management practices/CTNF	P/Nt/Ng
	Nature protected area	Yes/No	P/Nt/Ng
En	Forest management	BAU/Ecological agriculture and farming/No	P/Nt/Ng
	Agricultural activity	Production forests/Protective forests/Special purpose forests	P/Nt/Ng
	Forest structure	Yes/No	P/Nt/Ng
	Extreme climate events	Yes/No	P/Nt/Ng
	Forest cover [%]	Low < 60/medium 60–80/high > 80 3	P/Nt/Ng
	Cyanobacteria [problems with]	Yes/No	P/Nt/Ng

Note(s): ¹ P—Political, E—Economic, S—Social, T—Technological, L—Legal, En—Environmental. ² P—Positive, Nt—neutral, Ng—Negative. ³ The limits for low/medium/high were determined based on a mutual comparison of the reservoirs, when the analysed values represented an interval of ranked values.

) that influence water quality and were analysed in four case studies.

The information on each factor was collected using the various sources (

Table 4. Data origins.

Factor 1	Source
P	Interviews with stakeholders
	Water plan of Slovak Republic for the years 2022–2027
	Framework programme for monitoring water resources of Slovakia for the period 2022–2027
E	Interviews with stakeholders
	Costs for water treatment chemicals
	Water pricing tables
	Number of consumers
S	Interviews with stakeholders
	Medialised topics related to chosen WRs/Aktuality.sk, the biggest news internet portal and local media, if recommended by respondents/
T	Interviews with stakeholders
L	Interviews with stakeholders
	Act No. 364/2004 Coll. on Waters and on Amendments to Act of the Slovak National Council No. 372/1990 Coll. on Offences, as amended (Water Act)
	Regulation of the Government of the Slovak Republic No. 269/2010 Coll., establishing the requirements for achieving good water status;
	Decree of the Ministry of the Environment of the Slovak Republic No. 242/2016 Coll., establishing details on the definition of the administrative area of the catchment, environmental objectives, economic analysis and water planning
En	Interviews with stakeholders
	Act No. 364/2004 Coll. on Waters and on Amendments to Act of the Slovak National Council No. 372/1990 Coll. on Offences, as amended (Water Act)
	Regulation of the Government of the Slovak Republic No. 269/2010 Coll., establishing the requirements for achieving good water status;
	Decree of the Ministry of the Environment of the Slovak Republic No. 242/2016 Coll., establishing details on the definition of the administrative area of the catchment, environmental objectives, economic analysis and water planning
	Forest area coverage and forest categories

Note(s): ¹ P—Political, E—Economic, S—Social, T—Technological, L—Legal, En—Environmental.

).

3. Results

The results present findings for each water reservoir and outline the strategic implications of PESTLE factors impact the water management sector.

3.1. Case Study WR Málinec

The reservoir Málinec began to fill in 1994, and in 1999, the water reservoir was put into full operation. The Málinec reservoir is maintained under the Sub-basin management plan—Ipeľ and national and European strategic plans are implemented here. All water reservoirs are managed under the Water Directive and the National Water Plan, which focus on water quality and quantity. These documents and their measures have a positive impact on Slovakia’s water management sector. These are the basis for Sub-basin management plans elaboration. Moreover, the National Water Plan establishes measures related to the protection of water resources and controls the fulfilment of water quality indicators in Slovakia.

Decisions regarding reservoir management are issued by the State Administration of the Ministry of Environment, and when developing them, they incorporate elements to ensure water quality from various sectors, including environment, forestry, agriculture, and tourism. According to interviews with stakeholders, the cross-sectoral coordination was perceived to have a neutral impact on water quality.

The average annual water consumption from the reservoir is 2.60 milion m³ with 63,000 consumers in three districts: Lučenec, Poltár and Veľký Krtíš. The average cost for drinking water treatment (consumption of chemicals 2010–2022) represents 11.79 €.1000 m⁻³. Water treatment costs are average compared to other reservoirs in the study. In terms of water volume, the Málinec reservoir belongs to large sources among the analysed reservoirs (volume 26.7 million m³). The ratio of annual treated water to the total volume of the reservoir is 10%. This is the lowest ratio among the analysed reservoirs. The current capacity of the Málinec water treatment plant is approximately 280 l.s⁻¹. The costs of water treatment show medium variability over time (ranging from 7.8 to 13.6 €.1000 m⁻³, standard deviation 1.38).

The Ministry of the Environment has currently submitted an intention to build the Málinec pumped storage hydroelectric power plant [38]. Negative attitudes towards the issue were presented in the media and on social networks (M1). Local civil activists spoke out against the proposal and participated in the comment process (M1, M2). The proposal was heavily criticised and publicised at both the national and local levels. On the other hand, the construction of a pumped-storage hydroelectric power plant in the Málinec-Látky area should bring regulation and stabilisation of the energy network, investments in employment in the area, as well as a source of public revenue [38]. The potential construction of a pumped storage power plant may cause higher water treatment costs (higher turbidity or pollution of raw water caused by increased water turbulence). Currently, the conflict between the government and local communities has a neutral impact on water quality and quantity. However, it points out that the preparation of strategic decisions at the central level (top-down) in the initial phase does not adequately consider the participation of local stakeholders. The relationship between the water management utility and local stakeholders such as forest owners and agricultural cooperation or local inhabitants is strong, and they cooperate (M1, M3). Related to recreation, in protective zone I (PZ I) the all water-based recreational activities are restricted. Conversely, the recreational potential around the reservoir is high because there is a built road network for tourist and cycling activities. (tourism, cycling). There are marked cycle trails located outside the sensitive areas, thus not affecting water quality.

The water reservoir has problems with the technological equipment of water treatment, which has undergone a complete reconstruction. However, the reconstructed technology for water collection and treatment is currently in trial operation. So far, it appears that the technology is more susceptible to failures of individual technological elements (M1, M2). From a technological point of view, drinking water treatment consists of the (i) removal of coarse impurities, (ii) coagulation and flocculation, (iii) sedimentation, (iv) filtration, (v) disinfection and (vi) distribution. Technical problems occur in sedimentation and sludge management. The sludge management system now has a lower capacity and a higher failure rate compared to the previous system. The new operational water treatment technology does not reduce costs (M2). Water can be taken flexibly depending on the quality from four horizons, which has a positive effect on water quality. The withdrawal is carried out mainly from the two highest levels. A class III road runs nearby on one side of the reservoir (III./2715). Chemical sprinkling and slag are prohibited during winter maintenance. The rules are followed during road maintenance, and there is no problem with water pollution (M1, M2). The reservoir includes 3 small hydroelectric power plants with a total maximum output of 334 kW. These have a neutral impact on water quality, due to their location on the dam structure and absence of sediment disturbance.

The water protection restrictions are based on the Water Act and apply to the management of all water reservoirs in Slovakia. Special restrictions result from decisions made by the District Office in the regional seat, the Department of Environmental Protection. They are generally designed to ensure the good ecological status of water resources.

The restrictions specific for reservoir are as follows:

• Water related restriction: Prohibition of swimming in watercourses and any other activity that may endanger water quality. A permit is required for groundwater abstraction in the vicinity of the reservoir based on a hydrogeological assessment (data on the amount of water abstracted by calendar month is submitted to the reservoir administrator once a year).
• Environmental restrictions: Parking is prohibited outside areas designated for this purpose, i.e., only on paved areas. Construction is prohibited in I. and II. PZ. New buildings are permitted to be built only in PZ III., at least 50 m from watercourses and spring areas, with a precisely defined number of buildings (e.g., maximum of 30 buildings is permitted in the Smilná locality).
• Forestry restrictions: Management restrictions apply to PZ I and PZ II. Forest enterprises/owners must comply with the rules during logging and subsequent concentration of wood. These activities must be carried out in a manner that ensures the quality of water resources and does not compromise it through their operations.
• Agricultural restrictions: Ecological farming is required in protection zone III. The storage of pesticides and industrial fertilisers in floodplains, coastal lands and variable areas of watercourses throughout the catchment is also prohibited.
• There are violations of restrictions in the area, mainly regarding the occurrence of prohibited fishing and unauthorised entry into PZ1 (M1).

The three protection zones have been established around the reservoir. The PZ I is covered by spruce forests that are prone to calamity, i.e., accidental felling due wind outbreak. The PZ II spreads 50 metres from the water surface and is covered by broadleaves (dominantly oak and beech). The forest in protection zones I and II are categorised as a special-purpose forest with primary hydric function. The state forest enterprise mainly manages the forests, and there are no problems related to the forest management activities (such as logging and harvesting) (M3). On the contrary, differentiated management of special-purpose forests has a positive impact on the quality and quantity of water in the area (M1, M2, M3). The local agricultural cooperative practises use ecological farming. Cattle and sheep herds are also located nearby; their presence does not affect the operation of the reservoir (M3). The reservoir currently has no problems with cyanobacteria or other bacteria (M1, M2). The area has 57.47% forest cover, the least of the analysed WRs. Increasing the forest cover in the catchment would contribute to improving water quality. WR is located at a low altitude with a risk of drought in the summer months. As a result of drought, the location is prone to disasters in spruce stands, which negatively affect water treatment. The occurrence of disasters and the subsequent change in the species composition of stands in PZ I negatively affect the quality of raw water.

3.2. Case Study WR Turček

The WR Turček has been in partial operation since 1996 and has been in full operation since 1999. It is the youngest water reservoir in Slovakia. The reservoir is listed among the water management significant water bodies of the Slovak Republic and is maintained under the Sub-basin management plan—Váh. The secondary mission of the water reservoir is to protect the upper catchment of the Turiec region from floods. The average annual water consumption from the reservoir is 3.64 mil m³ with 89,000 consumers in three districts—Žiar nad Hronom, Handlová, and Prievidza. The average cost for drinking water treatment (consumption of chemicals 2010–2022) represents 14.98 €.1000 m⁻³. Water treatment costs are average compared to other reservoirs in the study. In terms of water volume, the Turček reservoir belongs to small-sized sources among the analysed reservoirs (volume 10.6 million m³). The ratio of annual treated water to the total volume of the reservoir is 34.3%. The average production of treated drinking water is at the level of 120 l.s⁻¹. The maximal capacity of the reservoir is 250 l.s⁻¹. The costs of water treatment show the highest variability over time (ranging from 7.6 to 23.7 €.1000 m⁻³, standard deviation 6.04). In the case of WR Turček, the high variability in water treatment costs is due to the suppression of the cyanobacteria Planktothrix rubescens, which has appeared in recent years. A significant increase in water treatment costs began in 2015 (T1). The cost for water treatment was the lowest till 2015 compared to other reservoirs.

According to respondents, no conflicts or issues were reported with stakeholders (T1, T3). However, a residential development is planned for the area, which may impact water quality in the future. According to official developer statements, these construction plans do not affect water quality, as future construction depends on the expansion of the water supply channel, which will also bring new investments for the reservoir. As in the previous case, recreational activities on the water body are not permitted, and stakeholders have not reported any instances of illegal fishing or entry (T1, T2). In general, restrictive measures are adhered to and monitored, but violations of the entry ban or fishing ban cannot be completely ruled out. The area around the water reservoir has recreational potential, because of the existing road network. A cycle trail runs around the reservoir, and a marked hiking trail runs along one side of the reservoir.

The water treatment technology is relatively modern and considered adequate. The reservoir’s advantage is its great depth. Water can be withdrawn from three depth horizons. The choice of the withdrawal horizon is based on the quality of the water and the possible occurrence of cyanobacteria, the amount of which varies in individual horizons depending on the season. Water withdrawal is most often carried out from the middle horizon (T1, T2). The hydropower potential of the water is used by three small hydroelectric power plants, with a total maximum output of 327 kW. The restrictions are based on national law and specific decisions of the regional Department of Environmental Protection:

• Water-related restriction: There is an entry ban in the PZ I area, and construction is prohibited in PZ I and PZ II. The new resident construction plans must include an application for new construction and the establishment of new collection points.
• Environmental restrictions: The PZ I includes the water body and the surrounding forests. the PZ II extends across the watershed and covers 2855 ha of forest. The Turček does not have PZ III. The entry ban for all motor vehicles applies to protection zones I and II.
• Forestry restrictions: Forest owners must obtain permission for their performance (forest management) in PZ I. All forests in PZ I are declared as special-purpose forests. The use of ecological motor oils is required, and differential forest management practices are applied. Related to logging—a ban on crossing the river with timber during logging; it is mandatory to collect wood residues to leave as little waste as possible at the logging site; and an obligation to mow the banks. The forest owners has to afforest the area predominantly with coniferous trees (pine and spruce), up to 20% of the afforested area could be non-coniferous trees.
• Agricultural restrictions: Generally applicable restrictions, but not applicable to the study.

There are two protection zones around the reservoir—(i) PZ I applies up to 100 metres from water level, and no one is allowed to enter this area and owners of the land need permission to manage their land (forests); (ii) PZ II applies up to watershed what represents area of 29 km squares. The declaration of protection zones has a positive impact on water quality. In the past, special-purpose forests were declared around the reservoir. Currently, there are productive forests managed following the decision of the Regional Environmental Office with management restrictions aimed at protecting water resources. The enterprise employs differential forest management practices and ensures the use of ecological engine oils and technology provided by forestry service contractors. Moreover, they adhere to the principles of forest management in the protection zones of the water source. Turček Reservoir is the highest situated water reservoir (777 m above sea level). Unlike other reservoirs, there is no acute problem with the death of spruce trees and the subsequent occurrence of disasters. The higher location of the Turček Reservoir with colder water was a prerequisite for a reduced occurrence of algae and cyanobacteria. Higher water temperatures usually accelerate the growth and reproduction of many species of algae and cyanobacteria. However, some cyanobacteria prefer lower water temperatures. The reservoir currently experiences problems with cyanobacteria due to its colder water temperatures (T1, T2). Planktothrix rubescens, which originates from Scandinavia, has been detected (T1, T2). Planktothrix rubescens is a water cyanobacterium that produces toxins and is a potential risk to human and environmental health [39]. This, coupled with the fact that the reservoirs have not been dredged or maintained since their initial operation, has led to a deterioration in water quality and increased water treatment costs (T1, T2).

The area has a 97.13% forest cover, which is the highest among all water reservoirs in Slovakia. This fact has a positive impact on the quality of drinking water. The high forest cover of the catchment area, or rather the mere existence of the forest, excludes the use of land for agricultural purposes. Agricultural activity is not carried out in the catchment area, or rather, it is carried out to a minimal extent (T1, T3).

3.3. Case Study WR Nová Bystrica

The Nová Bystrica reservoir is situated in the Kysucká Highlands and was constructed between 1983 and 1989 on the Bystrica River, where it has been in operation since then. The reservoir plays a crucial role in supplying drinking water to the Žilina and Kysuce regions, while also reducing flood flows and generating electricity. The Nová Bystrica is maintained under the Sub-basin management plan—Váh. The average annual water consumption from the reservoir is 7.05 mil m³ with 170,000 consumers in three districts—Čadca, Kysucké Nové Mesto a Žilina. The average cost for drinking water treatment (consumption of chemicals 2010–2022) represents 8.73 €.1000 m⁻³. Water treatment costs are the lowest among all reservoirs in the study. In terms of water volume, the Nová Bystrica reservoir belongs to the big-sized sources among the analysed reservoirs (volume 32.8 million m³). The ratio of annual treated water to the total volume of the reservoir is 21.49%. The average production of treated drinking water is at the level of 700 l.s⁻¹. The maximum capacity of the reservoir is 1050 l.s⁻¹. The costs of water treatment show low variability over time (ranging from 5.26 to 12.62 €.1000 m⁻³, standard deviation 2.13). These lower treatment costs are attributed to the high forest cover of the catchment (NB1).

The Nova Bystrica reservoir is not discussed in the media but only mentioned in relation to its flood protection of the valley. Respondents described conflict with non-state forest owners. They noted large amounts of waste after logging, mud-covered tracks on the weighbridges, and timber being transported along ditches and across streams (NB1; NB2, NB3). This is also influenced by the fact that in recent years, disaster timber harvesting has been carried out, which is reflected in the increased movement of mechanisms (NB3).

The Nová Bystrica reservoir utility uses a combination of mechanical and chemical water treatment, which is a standard approach for surface water treatment. The reservoir is currently under modernization processes. In 2000, an automated technology management system was implemented, and from 2001 to 2004, reconstructions of the buildings were carried out. Currently, public tenders have been announced for the development of project documentation to further reconstruct and modernise the water treatment plant facility. Water can be taken from four horizons (NB1, NB2). There are no significant problems with the occurrence of algae and cyanobacteria. The height difference between the water level in the reservoir and the bottom of the storage tank in the Považský Chlmec reservoir creates an energy potential that is utilised in three small hydroelectric power plants, with a total output of 265 kW. The area around the water treatment plant has recreational potential. A cycle path runs around the tank and a marked hiking trail is located on one side of the tank.

The restrictions are based on national law and specific decisions of the regional Department of Environmental Protection:

• Water-related restriction: Entry into the protection zone only with permission; in winter road maintenance, it is forbidden to use any sprinkler materials that could pollute the water.
• Environmental restrictions: Construction is prohibited in PZ I and II. The reservoir does not have a protection zone III. The entire Nová Bystrica catchment is part of the Kysuce Protected Landscape Area. The increased level of nature protection (II) has a positive impact on the quality of water resources.
• Forestry restrictions: forming the open timber storages; prohibition of the passage of mechanisms across watercourses; obligation to perform sanitation logging and clearing of afforestation after accidental felling and forest roads around the reservoir must not be constructed perpendicular to the reservoir’s water flow.
• Agricultural restrictions: Generally applicable restrictions, but not applicable to the study/environmentally friendly agriculture and ban on livestock grazing in PZ I.

The location’s advantage is its high forest cover (73.12%), which increases the quantity and quality of water in the landscape. The catchment was hit by a significant windbreak disaster, which resulted in an outbreak of bark beetles. Young deciduous stands predominate, and afforestation with coniferous trees is mandatory in PZ I (NB2). The forest in the PZ I is a special-purpose forest. The forests surrounding the reservoir and in Protection Zone II are productive. State Forest Enterprise follows all procedures related to the protection of the water source (NB3). Problems arise with small-scale non-state forest owners (NB1, NB2, NB3). The violations of forest management practices with an impact on water protection functions occurred during the processing of the accidental felling due wind calamity. The restrictions related to a ban on concentrating wood and timber storage, a ban on passing mechanisms across watercourses, and careless timber storage. Given the large number of small forest owners, it is also problematic to identify forest managers who violate these principles (NB1, NB3). Despite these facts, higher costs for drinking water treatment were not recorded during the processing of the calamity logging. The resulting clearings after the calamity logging are afforested mainly with deciduous trees. An increased proportion of deciduous trees in the future may seasonally negatively affect water quality (leaf fall and flushing into the water) (NB3).

As in the previous case, the high forest cover excludes the possibility of agricultural land use. In the past, sheep grazing was practised in more remote parts of the catchment, but it had a neutral impact on water quality. Currently, no agricultural activities are recorded except for meadow mowing (NB1, NB3).

3.4. Case Study WR Hriňová

The Hriňova reservoir, along with the Môťová reservoir, significantly influences the hydrological regime of the Hron River and is maintained under the Sub-basin management plan—Hron. These water structures were built as measures to ensure a sufficient water supply during periods of natural shortage and to provide protection against floods. The water reservoir was constructed between 1961 and 1965 and has been in operation since then. Together with the Málinec and Klenovec reservoirs, it forms an extensive water supply system that provides drinking water for a large part of south-central Slovakia.

The average annual water consumption from the reservoir is 3.93 mil m³ with 95,000 consumers in 5 districts—Detva, Lučenec, Poltár, Zvolen and Veľký Krtíš. The average cost for drinking water treatment (consumption of chemicals 2010–2022) represents 19.43 €.1000 m⁻³. Water treatment costs are the highest among all reservoirs in the study. In terms of water volume, the Hriňová reservoir belongs to the smallest source among the analysed reservoirs (volume 7.38 million m³). The ratio of annual treated water to the total volume of the reservoir is 53.25%. This is the highest ratio among the analysed reservoirs. The average production of treated drinking water is at the level of 125 l.s⁻¹. The maximal capacity of the reservoir is 260 l.s⁻¹. The costs of water treatment show high variability over time (ranging from 8.88 to 24.80 €.1000 m⁻³, standard deviation 4.59).

The reservoir has not been the subject of media interest and is not discussed among local actors. The area is sought by tourists, which is related to its location, as the reservoir is located in CHKO Poľana (a protected landscape area) but recreation on the water body is not allowed as in previous cases. The location of the reservoir within the protected area has a positive impact on water quality. This is caused by more restrictions than those found in common land. For example, wind calamities and bark beetle outbreak do not threaten the surrounding forests, there is no agricultural production, and chemical spraying is not allowed at all (H2, H3). A cycle path runs along one side of the reservoir, and a marked hiking trail is also nearby. The reservoir is relatively easily accessible, as State Road 529, Class II, runs alongside it. Road maintenance does not harm water quality, as chemical sprinkling and slag are prohibited during winter maintenance.

From a technological point of view, the reservoir uses outdated (original) technology for pumping and treating water. It is the oldest reservoir in Slovakia in terms of technology. Some elements are absent, such as UV lamps for water disinfection. However, they are preparing for a technology modernisation in the future, which will require significant investments (H1, H2). The problem with technology modernisation is that there are external conditions and principles that must be followed: Water can be taken from three abstraction horizons. In practice, however, water is typically abstracted from only one level. The hydropower potential of the reservoir water is used by two small hydroelectric power plants with a total output of approximately 50 kW (H1).

The restrictions are based on national law and specific decisions of the regional Department of Environmental Protection:

• Water restrictions: Development of selected areas is limited due to the location of the reservoir, and it is necessary to apply for a construction permit in the surrounding areas. These are the recreation and tourism centre Biele Vody and the residential area Vrchslatina. Swimming, boating and fishing are prohibited.
• Environmental restrictions: the reservoir has three protection zones (PZ I, PZ II, PZ III) with restricted activities as in previous cases. There is a protected bird area SKCHVU022 Poľana under NATURA2000 network.
• Forestry: The specific restrictions arise from the fact that the reservoir is located in a protected landscape area. Forest management is stricter and in selected locations (protection levels 4 and 5) some activities are completely prohibited. In the 5th protection level there is a no-intervention management regime.
• Agriculture: N/A

The location’s advantage is its high forest cover 86.92%, which increases the quantity and quality of water in the landscape. The forests in the catchments are predominantly special-purpose forests. They are under the management of the state forest, and there are no problems related to the forest management activities (such as logging and harvesting) (H3). On the contrary, differentiated management of special-purpose forests has a positive impact on the quality and quantity of water in the area (M1, M2, M3). The high forest cover, in combination with the reservoir’s locality, which is part of a Protected Area (Poľana), excludes the possibility of agricultural activities that could negatively impact the water quality. The forest surrounding the reservoir is in good condition, with no wind calamities (NB3).

3.5. Specific PESTLE Factors That Affect the Water Management in Slovakia

Table 5. PESTLE factors for chosen water reservoirs in Slovakia.

	Factor	Málinec		Turček		Nová Bystrica		Hriňová
		Criteria	Effect 1	Criteria	Effect 1	Criteria	Effect 1	Criteria	Effect 1
P 2	Water directive	Yes	P	Yes	P	Yes	P	Yes	P
	The Water Plan of Slovak Republic for years 2022–2027	Yes	P	Yes	P	Yes	P	Yes	P
	The Sub-basin management plan	plan Ipeľ	P	plan Váh	P	plan Váh	P	plan Hron	P
	Strategic management decision	Top-down	Ng	Top-down	Nt	Top-down	Nt	Top-down	Nt
	Cross-sectoral coordination	Yes	Nt	Yes	Nt	Yes	Nt	Yes	Nt
E	Demand	Low	P	Moderate	Nt	Moderate	Nt	High	Ng
	Supply	High	P	Moderate	Nt	High	P	Low	Ng
	Price	Moderate	Nt	High	Ng	Low	P	High	Ng
S	Relationships	Conflict	Ng	Consensual	P	Conflict	Ng	Consensual	P
	Recreation	No	P	No	P	No	P	No	P
T	Water treatment technology	Modern	P	Average	P	Modern	P	Primal	Ng
	Outdated treatment technology	No	P	No	P	No	P	Yes	Ng
	Water collection method	4 horizons	P	3 horizons	P	4 horizons	P	1 horizon	Ng
	Technological problems	Yes	Ng	No	P	No	P	No	P
	Hydroelectric power plant	Yes	Nt	Yes	Nt	Yes	Nt	Yes	Nt
L	Water, environmental, forest, agricultural restrictions	Yes	P	Yes	P	Yes	P	Yes	P
	Land ownership	State Forest/Farmers cooperative	P	Municipal forest	P	Small-scale non-state forest	Ng	State Forest	P
	Nature protected area	No	Nt	No	Nt	Yes	P	Yes	P
En	Forest management	Differential Forest management	P	Differential forest management	P	Differential forest management	P	Differential forest management	P
	Agricultural activity	Ecological agriculture	Nt	No	P	Ecological agriculture	Nt	No	P
	Forest structure	Special purpose forests	P	Production forests	Nt	Production forests	Nt	Special purpose forests	P
	Extreme climate events	Yes drought	Ng	No	P	Yes wind	Ng	No	P
	Forest cover	Moderate	Ng	High	P	High	P	High	P
	Cynobacteria	No	P	Yes	Ng	No	P	No	P

Note(s): ¹ P—Positive, Nt—neutral, Ng—Negative. ² P—Political, E—Economic, S—Social, T—Technological, L—Legal, En—Environmental.

presents a comparative overview of PESTLE factors (Political, Economic, Social, Technological, Legal, Environmental) for the four analysed water reservoirs in Slovakia: Málinec, Turček, Nová Bystrica, and Hriňová. This table offers a holistic assessment of the external environment affecting each reservoir and highlights the site-specific nature of water management challenges in Slovakia. Each factor is evaluated based on specific criteria and its impact on water management, categorised as Positive (P), Neutral (Nt), or Negative (Ng).

4. Discussion

Water management utilities are public service providers that differ significantly from conventional market-oriented enterprises. Their operations are heavily regulated and embedded in broader societal and ecological systems. As such, they must balance economic efficiency, technical performance, and public accountability [40]. The application of the PESTLE framework in this study proved useful for systematically identifying and categorising the external pressures these utilities face. Although PESTLE is traditionally used in corporate strategic planning, it proves equally relevant for public utilities by highlighting the complex external influences and interdependencies shaping their decision-making [41].

The results of case studies of four drinking water reservoirs (Málinec, Turček, Nová Bystrica, Hriňová) highlight the complexity of external factors influencing drinking water treatment management in Slovakia. In order to identify and structure these challenges, a PESTLE analysis was used, which includes political, economic, social, technological, legal, and environmental factors. The results show that these factors are interrelated, and their effects on water quality are often locally specific.

Political factors in the analysed reservoirs mainly manifest as tensions between central authorities and local communities. An example is the planned construction of a pumped-storage hydroelectric power plant in Málinec, which has provoked strong public criticism and resistance from local residents and civic initiatives. According to local testimonies, the affected communities learned about the project only from sporadic online reports and were given just a few days to submit their comments, without prior formal consultation. Residents and civic initiatives pointed to insufficient transparency, the absence of a proper environmental impact assessment, and concerns over potential deterioration of water quality. In connection with the project, two online petitions opposing its implementation were launched with almost 38,000 signatures [42]. This conflict highlights the lack of involvement of local actors in top-down strategic decision-making processes, which increases the risk of public resistance, implementation delays, and potential threats to water quality. A similar situation is emerging in Turček, where a new residential development is planned; unlike the Málinec case, no hydrological or environmental assessments have yet been carried out, so its potential impacts on the water regime remain unknown. These cases highlight the need to strengthen participatory mechanisms and communication with stakeholders, particularly in decisions with environmental or technical implications for water resources. Technical decisions, such as the construction of new infrastructure or the adoption of advanced treatment technologies, often involve complex trade-offs between efficiency, costs, and environmental safety, and their long-term impacts are more difficult for the public to evaluate without clear and accessible communication. Participatory planning has the potential to prevent conflicts, increase trust, and ensure higher public acceptance of decisions [43].

Economic factors significantly affect the efficiency and sustainability of drinking water treatment management, most notably through differences in treatment costs among the reservoirs. The analysis revealed that costs range from €8.73/1000 m³ (Nová Bystrica) to €19.43/1000 m³ (Hriňová), mainly depending on the technological level of the treatment plant, reservoir size, the ratio of extracted water to total volume, and the environmental condition of the catchment. Smaller reservoirs with lower technical sophistication, such as Hriňová, are more sensitive to seasonal and ecological fluctuations, which leads to higher cost variability. In contrast, larger reservoirs like Nová Bystrica show greater stability and resilience to these effects.

Social factors have proved to be key to the successful application of protective regimes and the overall effectiveness of water resource management. The case of WR Nová Bystrica revealed problems arising from insufficient regulation and control of management by non-state forest owners, who repeatedly violate protection measures (e.g., crossing watercourses with mechanisms, inappropriate storage of wood). These violations do not only result from technical shortcomings, but often also from weak social ties, mistrust, and low levels of communication between local actors and water utilities. Experiences from Málinec and Hriňová show that well-functioning relationships between key actors contribute to rule compliance and reduce the risk of conflict. Public perception also plays an important role—the way in which management interventions and decisions are communicated can affect their acceptance. Media discourse and potential dissemination of misinformation can create unnecessary public pressure and polarisation [44], as seen particularly in the case of WR Málinec. Transparent communication and public engagement are key to maintaining social sustainability. The recreation use as external factor showed that restricted recreation on water bodies (in all cases) has positive impact on water quality. The recreation activities in surrounding area (e.g., hiking or biking) has no impact on water quality in case that it is not banned due nature protection legislative (cases of WR Málinec and WR Nová Bystrica).

Technological factors play a crucial role in ensuring the quality of treated water and optimising the operational costs of water utilities. The findings from the case studies confirm that the technological level of individual treatment plants varies significantly and directly affects the water treatment costs and water quality. The treatment plants in Turček, Nová Bystrica, and Málinec represent the most technologically advanced examples, enabling flexible water withdrawal from multiple horizons. Automated process control allows for performance optimisation and loss reduction. At the same time, however, it turns out that even modern technologies are not immune to new ecological challenges—the occurrence of the toxic cyanobacterium Planktothrix rubescens has significantly increased the costs of water treatment, confirming the need for continuous innovation and adaptation of technology to changing environmental conditions. On the other hand, the treatment plant in Hriňová operates on original, outdated technology, lacking modern water treatment elements. This technological insufficiency leads to high costs variability, increased risk of process failure, and inability to respond to changes in water quality.

Legislative and environmental factors play a crucial role in protecting the quality of water resources, particularly through the implementation of protection zones and management regimes in designated protected areas. The analysis shows that all four analysed reservoirs operate in accordance with legislation on protection zones, specifically zones PZ I and II, which aim to reduce the impact of anthropogenic activities in sensitive areas of the catchment. This leads to applying differential forest management activities in the water catchments and positively impacts the water quality. However, the effectiveness of legislative measures, is significantly influenced by the ownership structure and management of the given area. In locations dominated by state ownership and managed by state forests (e.g., Turček, Hriňová), it is possible to control compliance with the rules more effectively, thereby reducing the risk of undesirable interventions in the environment. These areas often also fall under enhanced protection regimes, such as protected landscape areas (PLA Poľana, PLA Kysuce) or Natura 2000 areas, which provide additional legal protection and limit agricultural and recreational activities with a potentially negative impact on water. In contrast, in cases like Nová Bystrica, where there is a high proportion of fragmented private ownership, violations of protection regimes are regularly reported. Agricultural activities in these areas appear to have a limited or neutral impact on current water quality parameters.

The results of our analysis show that high forest cover in the catchment has a direct positive impact on the physical and chemical properties of the water and reduces the need for intensive treatment [45,46]. On the other hand, negative environmental events, such windthrows or bark beetle outbreaks, can severely disrupt ecological balance and lead to salvage logging, increasing erosion, reducing landscape retention capacity, and degrading water quality. This scenario was recorded in Nová Bystrica, where uncontrolled interventions in forest stands posed environmental risks. Although these have not yet caused a sharp increase in treatment costs, they represent a potential threat for the future.

The existence of protected areas (e.g., the Poľana Protected Landscape Area, the Kysuce Protected Landscape Area, or sites within the Natura 2000) is also positive, as they limit chemical inputs, agricultural activity and recreational loads, thereby contributing to maintaining a favourable ecological state. This was also confirmed by Trenčiansky et al. [16], who used the Poľana region as a case study, documenting that a transition from intensive to ecological agriculture led to reduced concentrations of nitrogen, pesticides, and turbidity in watercourses, which significantly improved water quality parameters. Restricting the recreation and implementing sustainable forest management thus function as preventive measures that protect water resources from anthropogenic impacts.

Similarly to the Slovak context, international studies show that technological innovation in the water sector is influenced not only by the internal capacities of utilities, but also by the external environment. Neri et al. [17] identified key barriers to the implementation of new technologies in a case study of an Italian water utility, including social distrust, fragmented legislation, and weak inter-institutional cooperation. Although their study focused on water reuse—which is generally considered more controversial than other water treatment innovations—these factors are analogously applicable to broader environmental and technical innovations in water companies in Slovakia. The authors emphasise the importance of integrated planning throughout the entire value chain—from regulators and technology suppliers to end users. This approach is also inspiring for the Slovak context, where it is necessary to improve connectivity between water companies, municipalities, foresters and farmers. The issue is not only technical modernisation, but also systemic collaboration, which can critically and fundamentally affect the environmental efficiency and acceptability of innovations.

Modern approaches to water utility management, such as those presented by De Lange et al. [21], offer a useful framework for reflecting on Slovak challenges. The Water Utility Risk Integration Matrix (WURIM) proposed by the authors is a tool that allows integrating all components of urban water management—from drinking water supply, through drainage to stormwater management—into a unified risk management framework. Its development responded to urgent issues that are also relevant for Slovak utilities: ageing infrastructure, growing impacts of climate change, and urbanisation pressure. Experience from Canada confirms that fragmented approaches are insufficient to address complex environmental and technical challenges, and that integrated management—linking environmental, technological, and institutional factors can enhance the efficiency, resilience, and sustainability of water services.

Mijic et al. [47] also emphasise the importance of adaptive resilience planning (ARP) in the management of water systems. This framework is directly applicable to Slovak conditions, where utilities face complex challenges ranging from outdated treatment infrastructure and catchment regime changes to legislative and financial pressures. The ARP framework connects environmental, technical, and institutional factors into a coherent system, thereby increasing the ability of water utilities to respond to unexpected events and long-term trends.

The increasing complexity of challenges faced by water utilities also highlights the need for strategic planning that takes into account multiple interconnected factors. The study by Hatoum et al. [48] confirms the use of PESTLE analysis as an effective way to identify and manage change. In particular, environmental and legislative pressures were perceived as the main drivers of adaptation and innovation. Such a multidimensional approach can also be beneficial for the Slovak water sector, where the need to integrate technological advancement, climate resilience, legal reform, and societal expectations into a cohesive strategy for sustainable development is increasingly urgent.

This need is also highlighted by Holec [49], who in his analysis of the Slovak water management sector points out that climate change is causing a deterioration in the availability of water resources due to drought, fluctuations in precipitation and increased evaporation. This trend increases the pressure on water utilities, which must respond with complex adaptation measures—from infrastructure modernization, through changes in land use planning to new approaches to catchment management. According to the author, it is therefore necessary to systematically link environmental, technical and institutional aspects of water management. These findings underline the need for a flexible and long-term sustainable approach to strategic planning and decision-making in the water sector in Slovakia as well.

The strategic role of technological innovation and environmental standards as drivers of organisational transformation is further supported by international analyses [48,50]. In the Slovak context, this may mean the need for digital transformation of water treatment plants and the introduction of predictive water quality monitoring. At the same time, the authors emphasise that the implementation of innovations also depends on the regulatory and organisational framework—the current environment should support flexibility so that businesses can respond to climate challenges and growing societal expectations [51]. Without appropriate policy instruments and cross-sectoral coordination, utilities may lack the flexibility needed to respond effectively to climate pressures and rising societal expectations [52].

An important area that has proven to be key in assessing both external and internal challenges to water management is the level of preparedness of enterprises for the implementation of Directive 2020/2184/EU [53], especially in the area of risk management. Directive (EU) 2020/2184, known as the recast Drinking Water Directive, sets updated minimum requirements for drinking water quality across the EU. It introduces stricter limits for chemical and microbiological contaminants, applies a risk-based approach from catchment to tap, and strengthens transparency of information for consumers. Its implementation underscores the need for Slovak water utilities to enhance technological measures and stakeholder engagement to ensure compliance with the new requirements. An analysis of Polish water utilities [54] shows that most enterprises in Poland—especially smaller ones—do not have established risk management teams and often rely exclusively on legislative incentives from above. Such a situation can be assumed analogous in the Slovak context, especially when it comes to small and municipal water resources, which have limited technical and personnel capacities.

5. Conclusions

This study demonstrated that the management of drinking water reservoirs in Slovakia is significantly influenced by external, political, environmental, social, technological legal and environmental factors. By applying the PESTLE framework to four diverse case studies, we identified context-specific challenges and opportunities that affect the quality of raw water and the efficiency of its treatment on national level.

Although all water utilities operate under a common strategic and legal framework, the case studies revealed considerable differences in operational conditions, stakeholder relationships, and environmental risks. The most influential external factors include forest management practices in the catchment, occurrence of extreme weather events, quality and adaptability of treatment technologies, and the implemented restrictions. The study revealed that state has a strong position in the decision-making process in the water sector. Firstly, with its top-down approach to water reservoir management, secondly with legal factors that impact water quality and quantity. However, this approach has a positive impact on the drinking water in Slovakia, since maintaining good water status is also superior to public ownership (e.g., in the case of restrictions for foresters and farmers) or the public interests (e.g., in the case of a ban on recreation on water bodies). Future research could expand the number of case studies or conduct comparative analyses with similar systems in other Central European countries. In addition, integrating quantitative data (e.g., modelling pollutant loads or cost projections under different climate scenarios) could provide a more comprehensive understanding of the causal mechanisms linking external factors and water quality.