Norfolk Rivers Trust Partnership River Stiffkey Total Catchment Solution Balancing Nutrients
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Norfolk Rivers Trust Partnership River Stiffkey Total Catchment Solution Balancing Nutrients 1 Mission Statement: Norfolk Rivers Trust’s mission is to enhance the value of the aquatic landscape through encouraging natural processes, with benefits for wildlife and people. Funding for this project • Environment Agency 4 Years • Natural England • World Wildlife Fund • Tesco, Asda, J Sainsbury,Courtauld 2025 • Utility Companies • Land Owners • Local Funders – Wind – Solar - Other Phases of the Project • Phase 1 Current – Walk Overs – Farm Visits – Establish nutrient inflows and Create total Catchment Partnership Plan • Phase 1 a Deliver plan to local community and partners • Phase 2 Establish Additional Funding – Permissions – Permits and Water planning • Phase 3 Deliver improvement • Phase 4 Measure against set Catchment Water Quality Objectives 4 Examples of Silt Trap Interventions Integrated Constructed Wetlands Options Forest and Industrial (food ponds processing) intercepting Flood attenuation wastewater land drainage and treatment treatment Water management through the coherent reanimation of ‘integrated’ constructed wetland types In situ Recreational treatment of Municipal wastewater self cleansing landfill leachate treatment swimming pond Impact Nar silt traps and LWD 350 300 250 Lexham 200 Castle 150 Acre Manor 100 Farm 50 0 2010 2013 2015 Fish numbers on Nar: EA Electro-fishing data 2015 EA Stiffkey Map 8 WATER QUALITY IN THE STIFFKEY AND GLAVEN CATCHMENTS AND BLAKENEY HARBOUR Estuaries and Coasts Partnership Fund Project Summary ABOUT THE PROJECT WE DID NOT FIND EVIDENCE OF SIGNIFICANT WATER QUALITY PROBLEMS POSED TO THE ESTUARY FROM THE STIFFKEY AND GLAVEN CATCHMENTS Blakeney Harbour (Norfolk) offers excellent opportunities for Why do we think this? fishing, sailing and bathing and functions as a nursery and feeding ground for many species of birds, finfish and shellfish. FAECAL INDICATOR BACTERIA NUTRIENTS In 2015, the Stiffkey & Glaven transitional waters was given a “bad” classification on the basis of biological criteria § On average, bacterial loadings from sewage § The water samples had low concentrations of nutrients. (phytoplankton) under the Water Framework Directive (WFD). treatment works (STW) in the upper catchment are, The River Glaven was given “moderate” classification under on average, 100 times higher than the loadings from § The sites with higher levels of phosphates were: Binham WFD. STW in the lower catchment. Tributary, Stiffkey Bridge, Wighton Bridge (River Stiffkey) and Wiveton Bridge (River Glaven). We carried out an investigation in the Stiffkey & Glaven § Bacterial loadings from the River Stiffkey are, on catchments and in Blakeney Harbour to better understand the average, 10 times higher than the loadings from the § The ratio of nitrate:phosphate was higher in April– causes of these classifications and the sources of faecal River Glaven. September indicating greater mobilisation of nutrients in indicator bacteria (FIB) (E. coli), nutrients and phytoplankton. the growing season. § In the harbour, mean levels of E. coli in seawater WATER QUALITY INVESTIGATIONS were low (<10 cfu/100ml) at sites in the main harbour § At marine sites, the levels of dissolved inorganic channel. nitrogen decreased as salinity increased and were We collected water samples at 4 freshwater sites and at 7 characteristic of waters of “moderate” quality under marine sites during the period November 2016–September 2017 § Wildlife (seals, birds) contribute higher levels of E. WFD. during dry and wet-weather. Water samples were analysed for: coli to the harbour than river dischargesPHYTOPLANKTON. § Escherichia coli § Species of Alexandrium and Dinophysis were not found in any of the water samples. § Nutrients (nitrogen, nitrite, phosphate, silicate, ammonium) Most species of § Chlorophyll-a phytoplankton identified, § Karenia mikimotoi was found in two samples at low concentrations (100 cells/l). The such as Asterionellopsis § Suspended particulate matter highest concentration of Pseudo-nitzschia spp. was 140,910 cells/l. glacialis, were typically § Phytoplankton marine and harmless. We also measured salinity, temperature, phaeopigments, PROPOSED MEASURES TO ACHIEVE “GOOD” STATUS OF THE WATERS UNDER THE WFD fluorescence, turbidity, oxygen, salinity, temperature and photosynthetically active radiation at the water sampling sites. Farmers should apply fertilisers taking into account Water company could consider installing The investigation also included a re-analysis of historical WFD soil reserves and organic manure supply as advanced forms of treatment at Holt STW and monitoring data available for the study catchments. recommended by best practice Great Walsingham STW Maintenance of “good” status of the waters Escherichia coli are faecal is important to support a healthy bacteria used indicate Farmers should spread fertilisers and manures in Owners of septic tanks/small package sewage environment and protect human health contamination of human and low risk areas and at low risk times, avoiding treatment plants must ensure that tanks animal origins periods of rainfall perform well and do not contaminate surface waters Farmers should keep livestock away from Boat owners should adopt the watercourses through streambank fencing or recommendations of the RYA/British Marine bridging of streams Federation Love where you sail campaign WFD EA website – compare with CEFAS 2009 2016 OBJECTIVE Overall POOR Moderate GOOD by 2027 Eco POOR MODERATE GOOD by 2027 CHEMICAL NRA GOOD Protected Areas Nitrate NN SAC 10.