The Demonstration Test Catchments (DTC) project is a joint Defra, Environment Agency (EA) and Welsh Assembly Government (WAG) initiative seeking to develop an evidence base for more generic application to the management of river catchments across England and Wales.
The programme will initially set up three instrumented catchments with an integrative data infrastructure to provide a shared-use network as the framework for collaborative investigation and analysis. The overall objective is to provide robust evidence to test the hypothesis that it is possible to reduce, cost effectively, the impact of agricultural diffuse water pollution on ecological function while maintaining food security through the implementation of multiple on-farm measures. High resolution, flow-proportional sampling will be undertaken alongside in situ analysis using commercially-available multiple parameter water quality sensors and analysers for key determinants including phosphorus and nitrogen species, ammomnia, dissolved oxygen, pH, temperature, chlorophyll and sediment. A nested experimental design will be deployed, consisting of control and manipulated micro-catchments (~1-3 km2) upstream of sub-catchment monitoring stations (~10 km2) in order to maximise the scope for demonstrating positive water quality and biological response to on-farm mitigation in the short-term.
All monitoring and sampling equipment will be controlled by a sensor web platform permitting triggering, data interrogation and presentation. Data time series will be collected at regular intervals, quality assured and transposed to a data repository. The research platform seeks to underscore the benefit of using sensor webs to control multiple monitoring stations collecting high quality data on multiple water quality parameters.
