ADAS has recently aligned with the Westcountry Rivers Trust (WRT) and South West Water (SWW) to adopt the River Tamar as an official satellite to one of the sentinel demonstration Test Catchments (DTC) - the Hampshire Avon.
The expansion is supported by Defra and provides an excellent opportunity to assess the water quality and freshwater ecological responses to mitigation strategies funded by SWW through the Payment for Ecosystem Services (PES) scheme being implemented by WRT.
The expansion to the Ottery tributary of the River Tamar (Figure 1) will comprise three monitored sub-catchments: two manipulated sub-catchments on the Caudworthy Water tributary of the River Ottery and one control sub-catchment on the neighbouring River Neet. Monitoring in each sub-catchment will cover surface water quality (phosphorous and nitrogen species, and suspended sediment) and aquatic ecology (fish, macrophytes, macroinvertebrates, and diatoms). In addition, a multi-pollutant source apportionment framework developed by ADAS will be used to detect change in response to mitigation at the source end of the pollutant delivery cascade.
Proposed mitigation options for ameliorating local diffuse pollution pressures from agriculture include installing stream bank fencing, improving maize management, slurry storage, improved cultivation timings and feeder ring management.
Figure 1: Map showing the location of monitoring sites for the River Tamar DTC
1 = Control sub-catchment on River Neet, 2 & 3 = manipulated sub-catchments on River Ottery
For more information on the Tamar or Hampshire Avon DTC please see the website: www.avondtc.org.uk
Alternatively please contact the project lead: Professor Adrian Collins on 01902 693404 or email adrian.collins@adas.co.uk or the local contact: Fiona Grant on 01249 758213 or email fiona.grant@adas.co.uk.