In promoting a sustainable use of pesticides, farmers need to be aware of good agricultural practices to reduce potential emissions to the water system. This study consists of a five year monitoring in an agricultural catchment. The first two monitoring years aim at baseline monitoring. Thereafter, mitigation measures are implemented and the effect of the measures is evaluated in a further three years of monitoring. The monitoring strategy is a combination of time-integrated sampling to detect point losses and event sampling with a higher time resolution to evaluate losses following rainfall events. Erosion prevention measures are promoted particularly on fields with a fast connection to the river where the product is used.