Spatio-temporal trend assessment for water quality of Bevern stream, UK

Land use and human activities in a catchment can have considerable effects on the quality of water bodies. This study is an effort to assess spatial and temporal behavior of Bevern stream, England, using trend analysis and consequently, identify sources of contamination. Monthly and seasonal trends are generated for 5 locations along the stream, for NH, nitrate, DO, and PO4-3 using 10 years of data (2003-2013). Linear Regression and Mann-Kendall test have been applied. Spatial results show Spatham Lane, Plumpton Green, and Clapper’s Bridge locations with higher nutrient load compared to Swansyard farm and Plumpton mill stream, justified by the presence of numerous farms and agricultural fields including municipal effluent at Plumpton Green and discharge from wastewater treatment plants at SL and Clapper’s bridge. Temporally, Plumpton mill stream show decline in quality with decrease in DO levels providing evidence to the Wales treatment plant as possible source. In contrast, Spatham Lane conditions show improvement with time, in PO4-3 and NH3. Current trend analyses further provide evidence on vulnerable quality conditions at Clapper’s bridge. To conclude, Bevern stream show adequate oxygen levels overall for aquatic life but more attention is needed to control nutrient load coming from waste treatment plants, in order to avoid eutrophication in coming years.