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The cost-effectiveness of integrated diffuse pollution mitigation measures - ES0203

Defra’s Water Quality Division (Catchment Sensitive Farming Group) is working towards identifying practical on-farm methods for mitigating diffuse water pollution from agriculture (DWPA). Amongst other activities, this has involved commissioning a review by IGER and ADAS of diffuse pollution losses from different farming systems (‘Diffuse pollution inventory’: Haygarth et al., 2005). This inventory described the impacts of contaminants on water, the loss processes from land to water, the impacts of different farming sectors on losses, potential mitigation methods and any policy drivers for implementation of these measures. The report covered nitrate (NO3), ammonium (NH4), nitrite (NO2), phosphorus (P), sediment, faecal indicator organisms (FIOs) and biological oxygen demand (BOD). The inventory was essentially a synthesis of previous Defra-funded research, and it has helped to support policy development within the CSF Group.
The aim of the proposed project is now to improve on this inventory report to further assist Defra`s CSF Group in planning how to tackle DWPA, in particular: a better quantification of the cost-effectiveness of selected measures (for NO3, P and FIO control), and the production of a `user manual` detailing each measure, range of costs and effectiveness, assumptions used and where the measure should be applied.
The deliverables from the project will be (a) a provisional `user manual` describing the cost and effectiveness of a range of mitigation methods that
`joins-up` with other Defra-funded work, (b) additional information to be incorporated into a revision of the diffuse pollution inventory to be undertaken as part of a related, concurrent proposal `A revised diffuse pollution inventory and scoping study on the use of catchment-based diffuse pollution models`.
The user manual and associated cost-effectiveness assessment is particularly important and is being conducted to help Defra meet their policy needs in a short time window. The original inventory drew heavily on recently completed work on P and N costs curves and the emerging COST-DP report and scored mitigation methods in terms of effectiveness against all potential pollutants (excluding agrochemicals), practicality and cost of implementation. Defra WQD used this as a basis for further analysis, sorting all the measures into an overall ranking of the most effective measures for tackling DWPA. The outcome was that 16 of the 57 mitigation measures scored poorly for effectiveness in tackling DWPA and these measures were eliminated from further consideration. Of the remaining 41, most of the high-ranking mitigation measures related to manure and fertiliser management. Soil management measures were shown to be comparatively less effective. The next stage in the decision process, therefore, is to provisionally quantify the cost-effectiveness in relation to the 41 measures to support Defra WQD in developing policy to implement measures on farms. The proposed project differs from previous projects in that the aim is to provide specific information on specific measures answering specific Defra led policy questions and to integrate the effects of each single measure on N, P and FIO loss. This work is to be conducted in tight time constraints to meet the policy deadlines for Defra and is therefore to be interpeted as a policy guide in the short term and must be interpreted in context with other emerging and complementing studies such as COST DP and COST DP2.
Project Documents
• Final Report : The cost-effectiveness of integrated diffuse pollution mitigation measures   (157k)
• Final Report - Annex : Appendix I - User manual   (1895k)
Time-Scale and Cost
From: 2005

To: 2005

Cost: £108,999
Contractor / Funded Organisations
Institute of Grassland and Environment Research (IGER)
Environmental Protection              
Water Pollution