FET05
Title: Use of Swales to Mitigate Agricultural Pesticides Pollution
Contact: Chad.Staddon@uwe.ac.uk
Project:
Recent implementation of water quality policy, such as the EU Water Framework Directive (WFD),
has seen a move away from additional wastewater treatment to achieve compliance with drinking
water standards. Instead, water companies are expected to set up catchment management
initiatives with local stakeholders within catchments with water quality problems to try to reduce
the problem at source.
The Upper Thames Swales Project was initiated to investigate the effectiveness of physical
catchment control methods for metaldehyde and other oilseed rape (OSR) pesticides. Metaldehyde
pollution of surface water is a major problem for water companies as it is extremely difficult to
remove in the treatment process. Multiple failures of the 0.1ug/l standard for drinking water have
now occurred at treatment works across the UK. There is some field-level evidence that swales can
work to reduce pesticide pollution. However, this has yet to be demonstrated at the larger scale and
has not yet been proven for metaldehyde.
Testing the effectiveness of land management approaches in reducing pesticide load (especially
metaldehyde) in adjacent surface watercourses requires a much more robust understanding of how
metaldehyde and other pesticides behave in soil and vegetation and the effectiveness of land
management techniques, such as swales, buffers, margins and in-field strips, in promoting the
absorption of metaldehyde and other pesticides by the soil.
This PhD will use the outcomes of past and current research to
1. monitor pesticide pollution in the trial catchment and in two control catchments to determine
if there is a consistent and reliable improvement in water quality associated with swales, and
2. will also monitor the swales and determine the maintenance requirements, costs and
practical implications of using swales.
This PhD project is part of a larger initiative jointly funded and supported by UWE, Bristol, Royal
Agricultural University, Countryside and Communities Research Institute and Thames Water.