The River Itchen is world famous for the pristine quality waters ideal for the sport of fly fishing and many fish farms make use of the spring fed chalk streams to grow trout and provide great habitats for insects, fish and otters. However, there have been some high levels of phosphate and sediments recorded in the river. This led to the EA calling on WRc for catchment management modelling advice as they studied the interaction of river flows and water quality with fish farm, sewage, agricultural inputs including watercress farms.
The modelling showed that phosphate inputs in some parts of the river need to be reduced to meet the river phosphate targets which can only be achieved with all users of the catchment actively managing their impact on the River Itchen. The EA used these findings to inform their revisions to permits in the catchment.