5 Conclusions

5.1 Integrated water management

This report has considered the aims of the Bathing Water Directive, the Drinking Water Directive and the Urban Wastewater Treatment Directive in the context of the Water Framework Directive. The different water industry directives have specific roles in delivering their respective objectives. Rather than aiming to meet a particular objective under a water industry directive in isolation, consideration of the synergies between each of the water industry directives and the WFD can lead to benefits such as better integration of needs in the design of more cost effective measures in order to improve the status and quality of our waters. The WFD with river basin management plans provide a powerful framework for achieving integrated water management and stakeholder dialogue across all relevant sectors.

Water of good quality for human consumption and recreation is intrinsically linked with water that is good for the environment, and all are related to the same pressures and drivers; pollution from diffuse and point sources. For example, water from the environment supplies drinking water. Drinking water is treated to protect people from the risks posed by raw water. Common elements between the DWD and the WFD are the protection of the raw water source and its catchment. The consequence of lower raw water quality is a higher investment in treatment or water transfers, and higher water prices for the consumers. Considering sustainability on a broad scale, an improved understanding of the relationships and synergies between the DWD and the WFD would help integrated decision-making.

Under the WFD regime, full implementation of basic measures is required, including compliance with the UWWTD. Going beyond the requirements of the UWWTD to improve wastewater treatment may be identified in river basin management plans as a necessary measure for the water body to reach good status. Meanwhile, the improvements to a wastewater treatment plant undertaken to meet the UWWTD could feed into an overall improvement in status under the WFD. Focusing on the desired outcome and thinking more broadly than sector-specific solutions can enable improved information for decision-makers.

5.2 Water quality and impacts on the environment and human health

The main quality parameters of cross-cutting interest considered in this report are nutrient enrichment, organic pollution and microbiological contamination. 

Increased nutrient inputs can present risks to surface and ground waters. Excess nutrients can lead to eutrophication in surface waters, a process characterised by increased plant growth, problematic algal blooms, loss of life in bottom water and an undesirable disturbance to the balance of organisms present in the water. Nutrients in groundwater could be a source of pollution for surface waters, if rivers or lakes are influenced by groundwater. If polluted groundwater is used for drinking, it could also pose a risk to human health, requiring additional, often energy-intensive treatment or mixing with less polluted raw water.

The main sources of nitrogen and phosphorus are point source emissions from urban wastewater treatment plants and industry, and diffuse emissions from agricultural production. The integrated management under the WFD provides more instruments for the reduction of these pollutants at source; it is the key instrument to set quality objectives for pressures,  such as pollution, from these diffuse or point sources. Alongside the WFD, the UWWTD is one of the most important basic measures related to point sources. It has led to an increasing share of the EU's population being connected to urban wastewater treatment, and to overall increased water treatment levels. However, small-scale rural sanitation is not directly addressed by the UWWTD or any other European legislation, and its inadequacy in some locations poses a potential threat to water quality and public health.

Microbiological pollution of water intended for consumption or recreation is of primary interest for public health. Microbiological pollution originates mainly in both direct point sources (waste-water treatment discharges or even direct sewerage system discharges) and diffuse surface sources (especially manure run-off from livestock farming). The most frequent cause of microbiological pollution reported under the BWD is pollution from sewage as a result of system failures or overflows from sewerage works, water draining from farms and farmland, and animals and birds on or near beaches.

5.3 Information and public interest

With their focus on the human part of the water cycle, and the quality of water for human consumption and use, the three water industry directives are of significant public interest.

The BWD, in particular, considers the public interest obliging the responsible public authorities to provide information on each bathing water site to the public in an easily accessible format during the bathing season. The EEA publishes annual reports of European bathing water quality and provides information on the EEA website, including links to national websites.

While up-to-date bathing water information is available to the public at bathing sites, timely information on regional and local drinking water quality is frequently rather scarce.

For the UWWTD, the EC publishes regular implementation reports on improvements in waste water treatment. In addition, the information reported by the Member States can be found  in the Water Information System for Europe on the EEA website and the water data centre (WISE, http://water.europa.eu/).

5.4 Future challenges

As measures to reduce point source pollution improve, the significance of diffuse inputs will increase. Such inputs are typically more difficult to address and manage.

Surface water bodies can be affected by intermittent discharges of untreated wastewater from storm overflows in combined sewer systems (combined storm overflow (CSO)). This will occur where there is no or insufficient storm water overflow retention capacity. Often, the nearby watercourse (usually the surface water) receives the wastewater and water quality is affected as a consequence.

CSOs represent a multiple, diffuse and uncontrolled source of pathogens and pollutants and are one of the major threats to good bathing water quality (see chapter 2), and consequently to human health.

The long-term effects of climate change may also influence the degree of environmental impacts caused by intermittent discharges. Higher intensity rainfall may result in some overflows operating more frequently and with greater spilled volumes.

Diffuse pollution from agriculture can affect raw water supplies for drinking water, for example leading to the need for increased treatment or dilution with less contaminated sources. It can also affect water quality, where surface runoff transports nutrients, harmful chemicals and microbiological contaminants from manure into watercourses.

Emerging issues for water quality, which represent potential but as yet poorly understood risks, include newly-identified micropollutants, microplastics and antimicrobial resistance. Improving understanding of these topics, particularly the risk they might present to public health and water quality, represent new challenges.