The Drinking Water Directive (Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption) concerns the quality of water intended for human consumption. Its objective is to protect human health from adverse effects of any contamination of water intended for human consumption by ensuring that it is wholesome and clean.
The Drinking Water Directive applies to:
All distribution systems serving more than 50 people or supplying more than 10 cubic meter per day, but also distribution systems serving less than 50 people/supplying less than 10 cubic meter per day if the water is supplied as a part of an economic activity;
drinking water from tankers;
drinking water in bottles or containers;
water used in the food-processing industry, unless the competent national authorities are satisfied that the quality of the water cannot affect the wholesomeness of the foodstuff in its finished form.
The Drinking Water Directive doesn't apply to:
Natural mineral waters recognised as such by the competent national authorities, in accordance with Council Directive 80/777/EEC of 15 July 1980 on the approximation of the laws of the Member States relating to the exploitation and marketing of natural mineral waters and repealed by Directive 2009/54/EC of 18 June 2009 on the exploitation and marketing of natural mineral waters.
Waters which are medicinal products within the meaning of Council Directive 65/65/EEC of 26 January 1965 on the approximation of provisions laid down by law, regulation or administrative action relating to medicinal products and repealed by Directive 2001/83/EC on the Community code relating to medicinal products for human use.
The Directive laid down the essential quality standards at EU level. A total of 48 microbiological, chemical and indicator parameters must be monitored and tested regularly. In general, World Health Organization's guidelines for drinking water and the opinion of the Commission's Scientific Advisory Committee are used as the scientific basis for the quality standards in the drinking water.
When translating the Drinking Water Directive into their own national legislation, Member States of the European Union can include additional requirements e.g. regulate additional substances that are relevant within their territory or set higher standards. Member States are not allowed, nevertheless, to set lower standards as the level of protection of human health should be the same within the whole European Union.
Member States may, for a limited time depart from chemical quality standards specified in the Directive. This process is called "derogation". Derogations can be granted, provided it does not constitute a potential danger to human health and provided that the supply of water intended for human consumption in the area concerned cannot be maintained by any other reasonable means.
The Directive also requires providing regular information to consumers. In addition, drinking water quality has to be reported to the European Commission every three years. The scope of reporting is set out in the Directive. The Commission assesses the results of water quality monitoring against the standards in the Drinking Water Directive and after each reporting cycle produces a synthesis report, which summarizes the quality of drinking water and its improvement at a European level.
Photograph 1.2. Chlorinisation and pompage units in a drinking water treatment plant
1.4.2. Water Supply
Drinking water supply in the EU is organised by supply zones, i.e. geographically defined areas within which water intended for human consumption comes from one or more sources and within which water quality may be considered as being approximately uniform. The Directive makes a distinction between large and small supplies. Minimum water quality requirements are equal for both large and small supplies. However, monitoring requirements differ and Member States do not need to report on the small supplies. About 65 million people are served by small water suppliers. Sources of Raw Water In the EU, water supply is mainly fed by groundwater and by surface water, including artificial reservoirs. Water sources vary considerably between Member States. Overviews have been provided in earlier reports, and are collected by Eurostat. There are significant differences in the percentage between large and small supplies with much higher rates of groundwater sources for small supplies (84%). Groundwater contamination, in particular by substances difficult to detect like pesticides, and surface water contamination, increasingly influenced by climate change (floods, extreme rainfalls, rain overflow) can pose problems that are passed onto drinking water. A coordinated monitoring of groundwater and drinking water, along with putting in place climate change adaptation and mitigation measures would be beneficial for safe drinking water.
Photograph 1.3. A view from a water supply dam
1.4.3. Drinking Water Quality
In order to ensure that drinking water is safe for human consumption, the Drinking Water Directive sets out minimum water quality requirements. It identifies microbiological and chemical parameters that could pose a risk to human health when concentrations exceed certain thresholds. For each of the parameters, the Directive sets maximum concentration values that must be complied with. In addition to the microbiological and chemical parameters, the Directive identifies indicator parameters for the purpose of indicating a possible risk for human health and which requires remedial action only if further investigation confirms the human health risk. Reported data on these parameters show that drinking water quality in the EU is in general very good. The overall trend is also positive. For the large supplies, the vast majority of Member States show compliance rates for microbiological and chemical parameters of between 99% and 100%. For the few Member States showing compliance rates lower than 99%, reinforced action will be required to ensure that all citizens served by the large supplies concerned can safely use drinking water.
Monitoring and Information; The Directive requires Member States to ensure that regular monitoring of the quality of water intended for human consumption is carried out. However, monitoring approaches differ between Member States and even between different water supply zones within individual Member States, resulting in different levels and availability of monitoring data. This does not necessarily amount to a failure in meeting the legal requirements as the Directive allows for adapted monitoring programmes depending on the specific characteristics of the water supply zone. The analysis suggests, however, the need to review and better streamline the current monitoring approaches, considering in particular the WHO's risk assessment and risk management water safety plan approach. To address Member States’ monitoring and performance, the Commission is working on a so called "Structured Implementation and Information Framework" (SIIF), establishing systems at national level which actively disseminate information about how EU environment legislation is being implemented. This information is then brought together to provide an EU-wide overview. The Directive's requirement that up-to-date information on drinking water quality is made available to consumers could also be linked to such an information framework and be improved in this context. Drinking water data could also be more clearly linked to the Water Information System for Europe (WISE) which comprises a wide range of data and information collected by the EU institutions.
The Directive allows derogations from the drinking water quality standards under very strict conditions and limited in time. Such derogations may not constitute a potential danger for human health and may only be established if the supply of drinking water in the area concerned cannot otherwise be maintained by any other reasonable means. A derogation may not exceed a period of three years. However, where a Member State considers that a longer derogation period is required, it may grant a second derogation for a maximum period of three years and it must communicate the grounds for this decision to the Commission. In exceptional cases, a Member State may request a third derogation from the Commission. The Commission will in this case carefully assess the request and may either refuse the request or grant the derogation for a maximum period of three years.
The Commission considers that no new derogations to the drinking water quality standards should be granted for existing water supplies with the exception of situations of new unforeseen pollution sources or following the introduction of standards for new parameters or reinforced drinking water quality standards of existing parameters. For new supplies, derogations could be considered under strict conditions if the pollution sources can be remediated within an acceptable timeframe and in case no alternative to the new supply is possible.
Challenges EU policy on drinking water has led to the development of high drinking water quality across the EU over the past decades. However, in order to keep these high quality standards and address specific remaining challenges, there may be a need to further adapt the EU legal framework.
Specific action may be required as well to reduce leakages in the distribution networks. In about half of the Member States, more than 20% of clean drinking water is lost in the distribution network before it reaches consumers’ taps, while for some Member States the proportion is as high as 60%.
The analysis confirms that the Drinking Water Directive contributed to high quality drinking water across the EU, as demonstrated by the high compliance levels with the drinking water quality standards. Although enforcement is satisfactory and progress has been made in many areas, the following issues and challenges have been identified:
The supply of high-quality water, in particular in remote and rural areas, should be improved. Small water supplies in these areas require specific risk-based management approaches and the role of the Drinking Water Directive in this context should be explored.
Risk-based approaches to the management of big water supplies would allow for more cost effective monitoring and parameter analysis in relation to identified risks and provide better guarantees for the protection of human health, Methodologies for monitoring and analysis should reflect the latest scientific and technological developments.
New scientific information about chemical and other parameters in relation to the drinking water parameter list should be considered in line with the ongoing revision of the WHO drinking-water guidelines, including emerging pollutants.
Modern information technology and easier access to environmental information should be used to provide more up-to-date information for consumers, and to explore how to link different monitoring data with reporting and consumer information.
Implementation timescales and derogation mechanisms are out- of-date and would benefit from a general update and overhaul.
An EU-wide public consultation will be a first step towards a further in-depth assessment of the above mentioned challenges and how they could be best addressed. It may also identify additional issues to be tackled in order to ensure and further improve high drinking water quality standards across the EU.
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