Diffuse Pollution, Degraded Waters

Emerging Policy Solutions

image of Diffuse Pollution, Degraded Waters

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.



Foreword and Acknowledgements

Water of adequate quality is an increasingly scarce resource. Substantial investments in wastewater treatment plants and progress in controlling point sources of pollution have contributed to significant improvements in water quality in recent decades. But a focus on point source pollution as a means of improving water quality is reaching its limits. Water pollution from unregulated diffuse sources of pollution from both urban and rural areas continues to rise. Unless attention is turned to these sources, further deterioration of water quality and freshwater ecosystems can be expected as human populations grow, industrial and agricultural production intensifies, and climate change causes significant alteration to the hydrological cycle.


This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error