Groundwater quality

Dátum poslednej aktualizácie:13.12.2021

Téma

Voda

Značky

Definícia indikátora

The indicator describes the quality of groundwater within basic and operational monitoring and assessment of the state of groundwater bodies.

Jednotka indikátora

-

Metadáta

Related definitions:

The groundwater quality is the analysis of groundwater samples, which are determined for a set of indicators listed in the Government Regulation no. 496/2010 Coll.

The groundwater body is a defined amount of ground water of hydrological collector or hydrogeological collectors.

The groundwater chemical status expresses the extent within which the water quality is affected by pollutants and it is expressed in two status classes, a good status and bad status.

Monitoring of groundwater quality constitutes a systematic monitoring and evaluation of the quality and condition of groundwater.

The basic monitoring of groundwater is carried out in the river basin districts, based on the characterization and evaluation of human activity effects and their impacts on ground water quality. The basic monitoring of the groundwater lasts at least one year during the period covered by the Slovak Water Plan. In case of  groundwater bodies in which the previous monitoring showed a good chemical status, and which at the same time are not exposed to influences that could change their chemical status to unsatisfactory, the basic monitoring of groundwater lasts at least one year during the period to which three consecutive Slovak Water Plans apply.

The operational monitoring of groundwater is conducted in all bodies or groups of groundwater bodies that are, based on their characterization, evaluation of the impacts and results of basic monitoring, identified as being at risk of failure to achieve the environmental objectives. When selecting the monitoring points, ensuring the representativeness of obtained monitored data for the whole groundwater body or group of groundwater bodies is taken into account.
(section 14 of the Decree of SR MoAERD no. 418/2010 Coll.)


Methodology:

Slovak Hydrometeorological Institute has been monitoring the quality of underground waters within the national monitoring program since 1982.

In the years 1995 - 2006, the quality of groundwater was assessed under STN 75 7111 in 26 important water management areas (alluvial sediments, Mesozoic, neo-volcanic complexes), created by the objects of the SHMI basic network, supplemented with drillings and springs of used and unused resources. The quality monitoring plan was annually specified in terms of water management needs and with regard to capacity possibilities and defined funds.

Sampling of groundwater along with the basic field measurements are carried out according to operating procedures for groundwater sampling and in situ measurements of parameters that have been prepared for Water Quality Testing Laboratory (SL KV), and they meet the requirements defined by the technical standards applicable in Slovakia and EU. The actual sampling within the monitoring of Slovakia´s groundwater is carried out by sampling groups of the Slovak Hydrometeorological Institute (SL KV Bratislava, Banská Bystrica, Košice and Žilina), and in Bratislava and western Slovakia by an accredited Skúšobné laboratórium Perútka s.r.o., under the instructions of geoanalytical laboratories that analyse groundwater samples.

The selection of parameters for the quality of the groundwater evaluation has been adapted to the requirements of the WFD and SR Government Regulation no.496/2010 Coll., amending and supplementing SR Government Regulation no. 354/2006 Coll., laying down requirements on water intended for human consumption and quality control of water intended for human consumption, in which the Directive 98/83/ EC is incorporated.

Chemical analyses are carried out by the accredited geoanalytical laboratories of State Geological Institute of Dionýz Štúr in Spišská Nová Ves. The overview of analytical methods with detection limits is shown in the table.


Data sources:

SHMI


Related indicators:


Related international indicators:


Linked references:

Väzba indikátora k rozvojovým dokumentom a cieľom

Action Plan for Water Protection in the Protected Water Management Area of Žitný ostrov (2023)
 
The main goal of the Action Plan is to effectively protect the quality and quantity of groundwater on Žitný ostrov as the most important source of drinking water in Slovakia.
 
Therefore, the proposed preventive measures are mainly aimed at:
  •  preventing or limiting the entry of pollutants into the groundwater and preventing the deterioration of the condition of all groundwater bodies,
  •  reversing any significant and permanently upward trend in the concentration of the pollutant, which is caused by human activity, in order to gradually reduction of groundwater pollution. The key areas for which measures are proposed in the Action Plan were identified in the Problem Analysis. These are the following areas/problems:
  • excessive use and development of the territory threatening the quality and quantity of water in CHVO Žitný ostrov,
  • unsupportive legal regulations and weak enforcement of the law,
  • insufficient information system and connection of monitoring systems,
  • insufficient environmental awareness and education of professional and lay people public.
 
Based on the analysis and the established vision, specific goals were proposed:
  • sustainable use of the territory and its development,
  • safe drinking water taken from CHVO Žitný ostrov,
  • reduction of threats to groundwater quality from local sources of pollution,
  • reliable monitoring and information system,
  • environmentally responsible approach to the protection and use of water.
The implementation of the Action Plan will be evaluated in 2027. The measures will be evaluated and then, as necessary, incorporated into the update of the Water Plan of Slovakia, or to planning documents in other areas (e.g. waste management, environmental burdens, spatial planning).

 

The concept of the water policy of the Slovak Republic until 2030 with a view to 2050 (2022)

The concept formulates measures in ten areas of intervention and indicators and a time frame for the implementation of individual measures are assigned to them. The achievement of the target value is generally considered for the year 2030, unless another time frame is indicated. In the case of indicators where the initial value is not known, the expected development trend (increasing/decreasing) is indicated.

The concept of water policy focuses on ten priority areas, which are interconnected, and focuses on the area of ​​water use.

 3. Sustainable use of water

Goal 3.1. Sustainable and efficient use of surface and underground waters without endangering their quantity and quality

Goal 3.2. Functional crisis management in times of drought and water shortages

4. Water for all residents

Goal 4.1. Ensuring the supply of health-safe drinking water for all residents

Goal 4.2. Increasing the connection of residents to municipal wastewater treatment systems and increasing the share of treated municipal wastewater


Water plan of the Slovak Republic for period 2022 - 2027 - Update 2021 (2021)

Environmental objectives aim to ensure and improve the quality of aquatic ecosystems and sustainable, balanced and equitable water use. Environmental targets are defined for surface water bodies, the groundwater bodies and the protected areas.

Environmental target for underground water bodies is to perform measures aimed at:

  • Preventing or limiting entry of pollutants into underground water and at preventing deterioration of the condition of underground water bodies;
  • Protection, improvement and renewal of underground water bodies and at ensuring the balance between underground water takings and completing their quantity in order to achieve the good condition of underground water until 22 December 2015 and 2021 within the second planning cycle, or until 2027 within the third planning cycle;
  • Reversing the important increasing trend of the pollutant concentration that is caused by human activities in order to decrease the underground water pollution gradually.

 

Plan for the development of public water supply systems and public sewers for the territory of the Slovak Republic for the years 2022 - 2027 (2021)

A. Plan for the development of public water supply systems

The Water Supply Development Plan is a starting document drawn up in accordance with the requirements established by the European Union for the fulfillment of the basic condition for the financing of measures in the field of water management in the program period 2022 – 2027.
 
The goal of the Public Water Supply Development Plan is to analyze the conditions for ensuring the necessary level of drinking water supply, to establish priorities and conditions for its implementation.
The strategic goal of the development of public water supply systems is to increase the number of inhabitants supplied from public water supply systems and to ensure the supply of health-safe drinking water.
 
The plan for the development of public water supply systems proposes to implement:
  • construction of public water supply systems in villages without water supply systems
  • increasing the number of inhabitants supplied from public water supply systems
  • and ensuring problem-free supplying residents with safe drinking water without negative impacts on residents' health and the environment.
The strategic goal is to ensure that the supplied drinking water meets health safety requirements and the limits of drinking water quality indicators for all residents of the Slovak Republic. Municipalities within the reach of the constructed water systems will gradually be supplied with water and the inhabitants will be supplied with drinking water supplied from high-quality water sources. Water supplies should gradually be built in municipalities that are beyond the reach of current water supplies and large-capacity sources. In the case of municipalities that are currently without a public water supply system, a proposal is presented to solve the supply until 2027, or the following years, depending on available public financial resources. If no solution method is proposed for the village, this village will be solved after 2027.
 
Strategy of the environmental policy of the Slovak Republic - Greener Slovakia (2019)
 
Sustainable Use and Effective Protection of Natural Resources
 
Goals: A good condition and water potential of all water bodies through the restoration of river ecosystems will be accomplished.

1. Enough clean water for everyone

1.1 The prevention of water pollution

  • Illegally discharged waste water from households, commerce and services, but also from the industry or leakage from environmental burdens and agricultural activity, significantlypollute surface and ground water. Strengthening and streamlining of controls, documentation of legal waste water disposal and a threat of real effective sanctions will help limit these actions.


1.3. Elimination of adverse impacts on water courses

  • In terms of the impact on water status, there are three main groups of significant hydromorphological changes: a disruption of longitudinal connection of the rivers and the habitats, a disruption of transverse connection of wetlands and inundation with sewer and other morphological changes and hydrological changes. It is therefore essential to focus on the revitalization and re-naturalization of water courses and the adjacent riverine landscapes and to ensure the coherence of water courses, which is one of the basic conditions for the functioning of river ecosystems.
  • The prioritization of renewal of land improvement channels will be set, depending on their function and use. Land improvement channels can also drain water from areas, where it is necessary. For this reason, it will be important to assess where the operation and maintenance of channels is needed and where it is environmentally harmful.


Orientation, Principles and Priorities of the Slovak Republic Water Management Policy by 2027 (2016)

3. PRINCIPLES AND PRIORITIES OF THE SLOVAK REPUBLIC WATER MANAGEMENT POLICY BY 2027 AND FRAMEWORK PROCEDURES IN ACHIEVING THE OBJECTIVES:


With a view to water status improvement:

  • Ensure systematic and comprehensive monitoring of waters which is necessary to obtain data and knowledge about the real status of waters, long-term development and trends for the preparation of analysis and creation of development planning and concept documents, for the evaluation of taken measures effectiveness, and the setting of new measures necessary to achieve the objectives;

In order to ensure the efficient use of water resources:

  • Identify alternative sources of groundwater. These resources should be of good quality properties, long residence time and low vulnerability. Where there are not enough good-quality groundwater resources, it is necessary to look for alternative solutions within the surface waters, for example through water supply of available water systems;

 

Strategy of SR adaptation to adverse impacts of climate change (2018)

5. Strategy objectives

To propose appropriate set of proactive adaptation measures and mechanisms to their implementation within the framework of sectoral policies, development strategies and action plans at all levels of the process;

8. Proposed adaptation measures in individual areas

8.5.3. Water management

Adaptation measures in our country should be directed to the compensation of drought manifestations, i.e. the decrease of flows and water resource yields, as well as to minimization of adverse consequences of flooding, particularly of flash floods in mountain and foothill areas. Adapting to the climate change in water management area should be focused on the implementation of measures leading to the creation of conditions for the better management of runoff in the river basin.

Water is becoming a critical strategic resource of the country which must be protected, and its efficient and effective use must be managed, in accordance with an objective to ensure the sustainable development. Rightly, the biggest attention is paid to water resources, their conservation and the need for more efficient use.

Measures to prevent degradation of water by contamination

- reducing contaminants in water bodies in accordance with the Slovak Water Plan

Kľúčová otázka

Have the requirements for underground water quality been met?

Kľúčové zistenia

  • In 2022, the quality of groundwater was monitored in 630 objects, where possible penetration of pollution into groundwater from a potential source of pollution or their group is assumed to be captured.
  • In 2022, there was at least one object in all quaternary water bodies that did not meet the requirements stated in the government regulation, where the most frequent unsatisfactory indicators were manganese and total iron content, which points to the ongoing unfavorable state of oxidation-reduction conditions. Out of 58 monitored pre-quaternary bodies of groundwater, 24 did not exceed a single object. In 6 pre-quaternary formations, only one indicator was exceeded: total organic carbon, pH, manganese, conductivity, lead and promethrin.
  • There were 85 groundwater bodies in good chemical condition (80.2%), which represents an area of ​​53,207 km2.
Change since 2005 Change since 2015 Last year-on-year change
Neutralny trend Neutralny trend Neutralny trend
Since 2007, groundwater quality has been monitored in quaternary and pre-quaternary groundwater bodies as part of basic and operational monitoring. In the evaluation of the chemical status of groundwater bodies (GB) in the 3rd evaluation period (2013-2018), compared to the 1st period (2007-2008), an increase in the number of bodies in good chemical condition by 23 bodies was recorded, and compared to the 2nd period (2009-2013) ) by 21 GB, whereby in the 3rd evaluated period, 80.19% of GB achieved good chemical status. In the evaluation of the quantitative status of the GB, there was a decrease in the 3rd evaluation period (2013–2018) compared to the 1st evaluation period (2007–2008), and compared to the 2nd evaluation period (2009–2013) an increase in the share of departments in good quantitative status to 90.88% (1st evaluation period - 93.33%, 2nd evaluation period - 70.59%).
In both types of monitoring, unfavorable oxidation-reduction conditions come to the fore, as indicated by the exceeded values ​​of the Mn and Fetot indicators. The most frequent unsatisfactory indicator in all quaternary formations was the percentage oxygen saturation.
In 2022, the quality of underground water was evaluated according to the decree of the Ministry of Health of the Slovak Republic no. 91/2023 Coll., there was an increase in the number of monitoring objects of the state hydrological network to 630 (compared to 396 objects in 2021), the number of exceeded indicators also increased to 2,044 (1,360 indicators were exceeded in 2021). The latest current assessment of the state of groundwater bodies is processed for the needs of the Water Plan of Slovakia - 2nd update, which covers 106 groundwater bodies and is based on the reference period 2013-2018.

 

Sumárne zhodnotenie

The number of exceeded selected indicators in basic monitoring objects according to the decree of the Ministry of Health of the Slovak Republic no. 91/2023 Coll. in 2022
 



Red - number of exceedances
Blue - number of determinations
Source: SHMI

The number of exceeded selected indicators in operational monitoring objects according to the decree of the Ministry of Health of the Slovak Republic no. 91/2023 Coll. in 2022




Red - number of exceedances
Blue - number of determinations
Source: SHMI

 

Podrobné zhodnotenie

75 water bodies (16 quaternary and 59 pre-quaternary) were defined in Slovakia. Monitoring of the chemical state of groundwater was divided into basic monitoring, which is performed once every six years, and operational monitoring is performed annually. Operational monitoring is carried out in all groundwater bodies that have been evaluated as risky from the point of view of failure to achieve a good chemical status and is a prerequisite for the capture of possible penetration of pollution into groundwater from a potential source of pollution or their group. Groundwater quality was monitored in 630 objects in 2022. They are objects of the SHMI state hydrological network or springs. Groundwater samples in these objects were taken depending on the type of rock environment: 1 time in 249 pre-quaternary objects and 1 Quaternary object, 2 times in 44 pre-quaternary objects and 336 quaternary objects. The samples were taken in spring and autumn, when extreme conditions of groundwater should be captured. The results of laboratory analyzes were evaluated according to the Decree of the Ministry of Health of the Slovak Republic (MH SR) 91/2023 Coll., which establishes indicators and limit values ​​of drinking water quality and hot water quality, the procedure for monitoring drinking water and risk management of the drinking water supply system and risk management home distribution systems.

Conductivity values ​​measured in the field exceeded the indicative value given by government regulation 185 times out of the total number of 1383 determinations, pH with the exception of 29 samples was within the range of limit values. The most frequently exceeded indicators include Mn and total Fe, which points to the ongoing unfavorable state of oxidation-reduction conditions. In addition to these indicators, the influence of anthropogenic pollution on groundwater quality is indicated by the exceeded limit values ​​of Cl- and SO42-. The character of land use (agricultural areas) is reflected in increased contents of oxidized and reduced forms of nitrogen in groundwater, of which NH4 (146 times) and NO3- (127 times) contributed the most to the exceedance. In the objects of groundwater quality monitoring, in 2022 the permissible value set by the regulation was exceeded in the group of trace elements by indicators of As (48 times), Al (7 times), Ni (7 times), Hg (6 times), Pb (5 times), and Sb (1 time). The presence of specific organic substances in groundwater is an indicator of human activity. In 2022, a wider range of specific organic substances was recorded. From the group of polyaromatic hydrocarbons, which have a limit value given by Decree of the MH SR 91/2023 Coll., limit values ​​were exceeded for the indicators benzo(a)pyrene and the sum of polyaromatic hydrocarbons, in the group of volatile aliphatic hydrocarbons the limit values ​​were exceeded for these indicators - benzene, chlorobenzene, the sum of PCE and TCE, vinyl chloride and 1,2-dichloroethane (1,2 DCA). The highest concentrations of PCE and TCE, which exceeded the limit value of the decree, were recorded in object 309390 Moldava nad Bodvou in both sampling cycles. Furthermore, in the group of volatile aromatic hydrocarbons, the sum of dichlorobenzenes (1.2, 1.3 and 1.4) exceeded the limit value in object 270790 BA-Za Dynamitkou. The most frequent pesticides with concentrations above the limit value were promethrin, hydroxyatrazine (hAtz) and desethylatrazine, to a lesser extent atrazine (Atz), hydroxyterbutylazine (hTerbutyl), S-metolachlor, propiconazole, lindane, tebuconazole, terbutrin and the sum of pesticides (PLs represents the sum of actually measured values ​​of all monitored pesticides in one analysis). The influence of anthropogenic activity on the quality of groundwater is also expressed by increased concentrations of CHSKMn (27 times). In the group of general organic substances, the values ​​of total organic carbon were exceeded 102 times.

As follows from the purpose of the monitoring program, the basic monitoring observation objects are located in areas unaffected by human activity, therefore the groundwater also shows a better quality compared to the operational monitoring objects designed to capture the action of significant sources of groundwater pollution.

 

Evaluation of the quality of groundwater in the territory of Žitné ostrov (2021 - 2022)

As part of the monitoring of groundwater on Rye Island, the issue of unfavorable oxidation-reduction conditions comes to the fore, as indicated by frequent increased concentrations of total iron, manganese and ammonium ions. The prevailing nature of land use in the monitored area (urbanized and agriculturally used territory) is reflected in increased contents oxidized and reduced forms of nitrogen in waters. In addition to these indicators, the influence of anthropogenic pollution on groundwater quality is indicated by the exceeded limit values ​​of Cl- and SO42-. Exceeding the limit value of SO42- (sulphates) was recorded in a total of 22 cases. In the monitored period, increased concentrations of arsenic were recorded 21 times in the group of trace elements, 8 times in the left-bank riparian zone of the Danube (6013 Kalinkovo), 4 times in the middle part Žitného ostrov (7293 Veľké Blahovo), 2 times in the lower part of Žitného ostrov (2602 Komárno) and 7 times in the river zone of the Little Danube (6012 Vlky). In the group of trace elements, the limit value of Hg (mercury) was also exceeded 4 times, 2 times in the left-bank riparian zone of the Danube, 1 time in the upper part of Žitné ostrov and 1 time in the lower part of Žitné ostrov. In the upper part of Žitné ostrov, the limit value of Al (aluminum) was also exceeded and the limit value of Pb (lead) was exceeded 1 time in object 601095 Dobrohošť. For the other monitored trace elements, no increased concentrations were recorded during the monitored years. In 2021 and 2022, hydroxyatrazine (11x), hydroxyterbuthylazine (6x), desethylatrazine (8x) and promethrin (18x) were the most frequently involved in groundwater contamination from the group of pesticides. Other pesticides that exceeded the limit value in these years include atrazine (3x), lindane (3x), propiconazole (1x) and S-metolachlor (1x). In eight objects, the amount of pesticides exceeded the limit value given by Decree of the Ministry of Health SR 91/2023Z.z. (PLs represents the sum of the actual measured values ​​of all monitored pesticides in one analysis). From the group of polyaromatic hydrocarbons, which have a limit value given by Decree of the Ministry of Health SR 91/2023 Coll., this value was not exceeded in both years. In the group of volatile aliphatic hydrocarbons, vinyl chloride (chloroethene) exceeded the limit value in both years and the sum of PCE and TCE, especially in 2022. Most of the monitored specific organic substances were determined below the detection limit of the analytical method used.

 

 

Evaluation of the condition of underground water bodies

The evaluation of the condition of underground water bodies is performed by evaluating their chemical and quantitative conditions.
 
Out of the total number of 75 underground water bodies, the following bodies have been evaluated:

  • 11 underground water bodies in the bad chemical condition – 7 quaternary and 4 pre-quaternary
  • 64 underground water bodies in the good chemical condition


The good chemical condition was indicated in 85.3% of underground water bodies, i.e. 77.9% of the total area of bodies. The bad condition was indicated in 14.7% of underground water bodies, i.e. 22.1% of the total area of units.

The evaluation of the quantitative condition of underground water bodies is the assessment of the influence of documented impacts on the underground water bodies as a whole. The basic indicator of the quantitative condition of underground water bodies was determined to be the stabilized regime of the underground water level (or abundance of springs); the others included the balance evaluation of quantities of underground water and changes in the underground water regime based on the monitoring programme results. In the Slovak Republic, four underground water bodies were included in the bad quantitative condition.

Kontakt na spracovateľa

Ing. Ľubica Koreňová, SAŽP, lubica.korenova@sazp.sk