DiffuseTools Project: Catchment Models and Management Tools for diffuse Contaminants  (Sediment, Phosphorus and Pesticides)

The DiffuseTools Project (2016-W-MS-24) will develop catchment models and management tools to improve understanding of the transport and attenuation of diffuse contaminants in Irish landscapes. Feedback from stakeholders on the management challenges that are that are most pertinent in Irish catchments will direct this research. This project aims to inform catchment managers about potential sources of pollution within a catchment, including identifying critical source areas relating to sediment, phosphorus, and pesticides.


  • The agricultural sector is the most common suspected source of nutrient pollution in Irish rivers and lakes. However, it is also often the most difficult source to characterise due to its predominantly diffuse nature.
  • Particulate phosphorus in surface water and dissolved phosphorus in groundwater are of particular concern in Irish water bodies. Hence the further development of models and indices to assess diffuse sources of contaminants are required for use by the Irish Environmental Protection Agency (EPA) to provide support for river basin planning.
  • Understanding connectivity in the landscape is a vital component of characterising the source-pathway-receptor relationships for water-borne contaminants, and hence is a priority in this research.
  • The DiffuseTools Project will focus on connectivity modelling and incorporation of connectivity into sediment, nutrient and pesticide risk mapping.

DiffuseTools Project Objectives

i. Develop catchment models to improve understanding and enhance the evaluation of water quality, building on previous Irish and international research. The models will inform catchment managers about potential sources of pollution within a catchment, including identifying critical source areas (CSAs) relating to connectivity, sediment, nutrients and pesticides.

ii. Learn from International modelling experience: The project will strive to identify the state-of-the-art methods and models that are most applicable to Irish conditions and management challenges.

iii. Address critical knowledge gaps: An initial experts workshop will support this review.

iv. Produce compatibility guidance for researchers on the development of new tools and maps for the EPA’s modelling framework, to ensure continuous use, maintenance and upgrading of the tools available to catchment scientists and managers in Ireland.


Michael Bruen (PI), Eva M. Mockler (Co-PI), UCD Dooge Centre for Water Resources Research.

Research Assistant: Anna Rymszewicz

Project Participants:

Sim Reaney, Department of Geography, Durham University.
Per-Erik Mellander, Teagasc.
Andrew Wade, Department of Geography and Environmental Science, University of Reading, Reading.
Adrian Collins, Sustainable Agriculture Sciences, Rothamsted Research.
Berit Arheimer, Swedish Meteorological and Hydrological Institute.