Biodiversity, water and natural resource management
Diffuse Pollution, Degraded Waters
Emerging Policy Solutions
After decades of regulation and investment to reduce point source water pollution,
OECD countries still face water quality challenges (e.g. eutrophication) from diffuse
agricultural and urban sources of pollution, that is disperse pollution from surface
runoff, soil filtration and atmospheric deposition. The relative lack of progress
reflects the complexities of controlling multiple pollutants from multiple sources,
their high spatial and temporal variability, associated transactions costs, and limited
political acceptability of regulatory measures. This report outlines the water quality
challenges facing OECD countries today, presents a range of policy instruments and
innovative case studies of diffuse pollution control, and concludes with an integrated
policy framework to tackle diffuse water pollution. An optimal approach will likely
entail a mix of policy interventions reflecting the basic OECD principles of water
quality management – pollution prevention, treatment at source, the polluter pays
and beneficiary pays principles, equity, and policy coherence.
“OECD countries have struggled to adequately address diffuse water pollution. It is much easier to regulate large, point source industrial and municipal polluters than engage with a large number of farmers and other land-users where variable factors like climate, soil and politics come into play. But the cumulative effects of diffuse water pollution can be devastating for human well-being and ecosystem health. Ultimately, they can undermine sustainable economic growth. Many countries are trying innovative policy responses with some measure of success. However, these approaches need to be replicated, adapted and massively scaled-up if they are to have an effect.”
Simon Upton – OECD Environment Director
COUNTRY case studies
Full case studies submitted by member countries and international organisations for this project are presented below. Selected case studies have been included in this report. Several more of the case studies will inform the forthcoming OECD work on contaminants of emerging concern in surface water.
6 April 2017 (13:00 CET) - OECD Green Talks Live on Degraded Waters: Emerging policy solutions to tackle diffuse pollution - Hannah Leckie and Xavier Leflaive of the OECD Environment Directorate discussed emerging solutions in OECD countries, that can guide the design and implementation of policies to control diffuse water pollution.
22 March 2017 - OECD participation in the World Water Day 2017 Webinar on wastewater organised by International Water Resources Association (IWRA). Details on IWRA press release.
Global distribution of water pollution hazard, 2000
Note: Map includes the effects of nutrient and pesticide loading, mercury deposition, salinisation, acidification, and sediment and organic loading. Source: Sadoff et al. (2015); based on data from Vörösmarty et al. (2010).