Thematic Scope 2010

The Water Quality Challenge - Prevention, Wise Use and Abatement

The thematic scope frames the key issues and discussion points related to the 2010 theme "The Water Quality Challenge - Prevention, Wise Use and Abatement". The intention is to deepen the understanding of, stimulate ideas on, and engage the water community around the challenges related to water quality.

The challenge

Driven by demographic change and economic growth, water is increasingly withdrawn, used, reused, treated, and disposed of. Urbanisation, agriculture, industry and climate change exert mounting pressure on both the quantity and quality of our water resources. Our water resources - green and blue - face a daunting future and the costs of inaction are very high. We are confronted by a combination of escalating water scarcity, increasing demand for clean water, and worsening water quality, which severely restricts water-related human activities, affects human health, and impacts the health of aquatic and terrestrial ecosystems.

Virtually every corner of the world is exposed to the water pollution challenge. Although improvements have been made in some regions, water pollution is on the rise globally. Every day, an estimated two million tonnes of human waste are disposed of in watercourses. Seventy percent of industrial wastes in developing countries are dumped untreated into waters where they pollute the usable water supply. The complexity of the challenge is revealed by the many different forms that pollution can take, the range of pollution sources, and the varying scales - local, regional or global - at which pollution can develop. Lack of monitoring and enforcement also makes it difficult for countries and regions to understand and deal with this challenge. As with most challenges, however, opportunities exist that can reverse the water degradation trend, contribute to economic growth and improve human and environmental health.

The current situation and future solutions

Many human activities that produce a good also generate pollutants, indeed every human may be seen as a source of pollutants. These pollutants often find their way into sinks such as reservoirs, wetlands and aquifers. Within the context of global changes, the 2010 World Water Week will strive to highlight the more sobering aspects of the challenge: the pollution-causing activities, the prevalent and emerging pollutants, and the scale and trends of the impacts on human and environmental health. This will help to clarify the current status and convey the urgency, magnitude and pervasiveness of the water quality problem.

Examining how some countries and regions have responded to water quality degradation in the past may shed light on how to circumvent historical trends as we move forward. Learning from the association between development and water quality degradation in the past can help to prevent patterns from re-occurring as countries develop. By learning from what has worked and not worked, we can avoid a business-as-usual approach that would delay even further the recovery of ecosystems and lead potentially to irreversible shifts.

The 2010 World Water Week is an opportunity to gather and demonstrate the experiences, technologies and resources that people are mobilising in order to deal with water quality management problems. The Week will analyse promising examples, case studies and leading-edge technologies that are in use around the world. This will draw attention to effective response measures related to pollution prevention, wise resource use and sound abatement practices and allow for an analysis of the alternatives to improve the current and future water quality problems. Ideas, examples and initiatives are sought that will stimulate the discussion.

Significance of a flow perspective

Water is a solvent and transport mechanism continuously moving through the landscape. Human modifications of water systems and changes in land use have significant effects on surface and groundwater quality, which in turn has negative effects on human and ecosystem health. There is often a disconnect for people that pollute and the effects of that pollution on people and ecosystems downstream or in other parts of shared lakes and aquifers. The flow perspective can shed light on the creeping and often invisible nature of water pollution. Accumulation of pollutants over time in the natural sinks in the landscape can have considerable long term impacts on human and ecosystem health. Groundwater systems are especially vulnerable to pollution, as they are often difficult and costly to remediate. Some pollutants can occur in high concentrations even though the water can appear clean and safe.

Intensified resource use in all sectors is generally associated with increased loads of nutrients, sediments, chemicals, pathogens and metals. Tracing the pathways of these pollutants, from rain to drain, can help to shed light on many issues, including how pollution can contribute to the undermining of ecosystem resilience. Weakened resilience diminishes the capacity of ecosystems to cope, leading to tipping points and regime shifts. Sometimes these shifts are irreversible and the goods and services that humans derived from the ecosystems are lost.

Point and non-point sources of pollution

For analytical reasons and effective policy-making, it is useful to distinguish between point and non-point sources of pollution. Point sources include pipelines, channels and drains from
identifiable locations such as an industrial plant or landfill. Non-point or diffuse sources of pollution arise from extensive land areas and are mobilised by precipitation and thus closely
related to the hydrological cycle. Agricultural and urban runoff and air borne particulates are examples of diffuse sources, and their entry points to receiving waters are often difficult to
identify. Diffuse pollution sources are significant due to their far reaching geographical and temporal effects and the difficulty to contain them once they are in the water systems. For non-point pollution in particular, prevention is the most effective measure. Harmful production, consumption and disposal practices need to be monitored, controlled, and where possible prohibited, to prevent hazardous substances from reaching water bodies and
impacting human and ecosystem health.

Integrated approaches and the human dimension

The identification of the source and level of pollution is the first step in assessing the risk that pollution poses. Pollutants have a sender and a receiver and these must also be identified as part of any approach. With this knowledge, abatement strategies can be put in place that utilise technologies. Implementation of an integrated pollution prevention and control strategy should take into account the interfaces between air, land and water. It also must address economic policies and transboundary implications that can enable or hinder effective pollution abatement. An integrated approach to water quality management can help to identify situations where a pollutant in one area can be used as a valuable resource in another. A case in point is phosphorus, which is often the cause of eutrophication, yet is also a scarce resource for which there is no substitute in food production. By reusing and recycling wastewater, gains in water use efficiency can be realised. An exploration of the connection between water quantity and quality can lead to situations where demand is met, scarcity is eased and water quality is improved.

Finally, the institutional arrangements as well as individual responses to pollution must be adequately analysed. There are various ways to prevent and mitigate pollution. The "Polluter Pays Principle" asks the sender to pay for the pollution mitigation, thereby transferring the costs to those that are responsible, and in turn stimulating new innovative solutions. Another method is "Name and Shame", where those that are found to be polluting water systems are publically singled out, with the aim to deter future recurrences. What other strategies exist to prevent and mitigate pollution? What institutional obstacles exist that may inhibit the implementation of pollution policies? Is there a role for media and the general public in facilitating decisions at all levels of government and society?