Nene Catchment Partnership - Your Water Catchment River Nene Headwaters Water body ID: GB105032045310 The River Nene is the tenth longest river in the UK. It’s most westerly point (headwaters) is on the northern slope of Arbury Hill. The water catchment area of these headwaters is highlighted in black on the map above. This bulletin provides a summary of the available water quality data for the catchment, and some of the key environmental features and issues. Updated Jan 2016 The Catchment The River Nene starts on the northern slopes of Arbury Hill. From here it flows east through the villages of Badby and Newnham before it is joined by the Everdon Brook. It then continues east towards the village of Weedon and on to Northampton. There is a drinking water abstraction point at Duston Mill in Northampton. The catchment is mainly rural, with several feeder streams along its length and some woodland areas. Agricultural practices consist of predominantly arable with semi improved and improved grasslands for grazing. Current Status This section of the river Nene (Water body ID GB105032045310) is currently classified as Poor Status under the Water Framework Directive (WFD). The WFD requires that all water bodies achieve Good Status by 2027 and the Nene Catchment Partnership is working to achieve this. The Environment Agency has one routine water quality sampling site on this stretch of the river where water quality is monitored approximately 12 times per year. We also monitor the status of the river biology at Newnham, looking at both macrophytes (aquatic plants) and invertebrate species. The map below shows the location of the Environment Agency monitoring points: Phosphate Phosphate is the most common failing element nationally under WFD. The target for Good Status for phosphate is calculated on a site specific basis (depending on other water body characteristics such as altitude), and for this monitoring point is 0.073mg/l, measured as an annual average. Phosphate pollution may originate from point sources, such as sewage treatment works (STWs) and septic tanks, or from diffuse sources. By diffuse sources we mean from a range of activities and scattered sources that individually may have little effect on the water environment, but added together when they enter a water body can have a significant effect on the water quality. The most common way phosphate gets into watercourses from agricultural sources is attached to soil particles. Reducing soil erosion and runoff is therefore a key way to reduce this nutrient input into rivers. The Environment Agency collects data on the levels of phosphates in the Nene at the Dodford Road bridge, as shown on the above map. The graph below shows that the phosphate levels in this watercourse exceed the WFD target with annual averages of 0.09mg/l in 2012, 0.09mg/l in 2013 and 0.12mg/l in 2014. We have assessed this water body and consider that it is likely to be at risk from phosphate pollution from agriculture. Newnham STW will also be contributing to Phosphate levels. All catchments are different, but generally it is thought that, in rural catchments, agriculture inputs approximately 35% of phosphate into the water and STWs about 60%. The most common way phosphate gets into watercourses from agricultural sources is attached to soil particles. Phosphate will also enter the water in the following ways: manures or fertilisers direct from overspreading or from leaks and spills or washed off the field surface water and wind erosion of soil carrying phosphate attached to clay and organic matter there can be significant leaching of dissolved phosphate through the actual soil profile when levels reach P index 4 and above soil sediments and manures, containing phosphate, reaching field drains. This is increased in cracked or recently fissured soils (e.g. land drainage, deep subsoiling or mole draining) Excessive nutrients in the watercourse damage the environment by upsetting its natural balance. It encourages more aggressive feeding plant and animal species that are more likely to take over a water body, thriving at the expense of other species. This reduces the biodiversity of the watercourse. Sediment itself also affects the habitat of rivers by smothering riffles used by fish to spawn and changing river morphology. Managing and reducing sediment runoff can help to prevent damage to the environment and maximise the levels of phosphates retained in soil for crop growth. Nitrates The catchment of this part of the River Nene, along with much of England, is in a Nitrate Vulnerable Zone (NVZ). Assessments have shown that this catchment is at risk of nitrate pollution from agriculture. Nitrate pollution problems can occur when too much chemical fertiliser is applied to the land. The excess runs off and can find its way into drinking water sources, rivers and lakes. European legislation states that drinking water should not contain more than 50 milligrams of nitrates per litre of water. In rivers, streams, ponds and lakes, too much nitrate can create a 'pea soup' effect. The water becomes clogged with fast-growing plant life like algae and weeds. This is a major problem especially in some areas of England such as East Anglia. In problem areas, some farmers voluntarily control their use of nitrogen. Surface waters are considered to be ‘polluted’ by nitrates where levels are in excess of 50mg/l. Monitoring shows that Nitrate levels in this water body are below this threshold. However, good practises are still important to ensure this remains the case, and protect the Nene downstream. Pesticides The drinking water limit for any pesticide is 0.1µg/l. There is no monitoring in the headwaters of the river Nene for pesticides; however levels are monitored downstream on the Nene at Duston Mill, Northampton where there is a drinking water abstraction point. The graphs below show levels of pesticides detected at Duston Mill, along with a list of the most common products containing that active ingredient. The highest levels detected are for Metaldehyde, which is discussed in more detail below, and peaks tend to occur in autumn. Concentrations greater than 0.1 µg/l have been detected for all 5 of the pesticides shown below. The headwaters of the River Nene are within the River Nene drinking water at Duston Mill Nene thePesticidesin River practices. Safegua Clopyralid µg/l Metaldehyde µg/l 0.5 1.5 2.5 3.5 4.5 0.05 0.15 0.25 0.35 3 4 5 0 1 2 0.1 0.2 0.3 0.4 0 e.g. e.g. 12-Jun-08 rd Zone, and the presence of pesticides 12-Jun-08 12-Sep-08 12-Sep-08 12-Dec-08 12-Dec-08 12-Mar-09 12-Mar-09 Lontrel Curtail Confront Slug pellets 12-Jun-09 12-Jun-09 12-Sep-09 12-Sep-09 12-Dec-09 12-Dec-09 12-Mar-10 Metaldehyde 12-Mar-10 12-Jun-10 Clopyralid 12-Jun-10 12-Sep-10 12-Sep-10 12-Dec-10 12-Dec-10 12-Mar-11 12-Mar-11 12-Jun-11 12-Jun-11 12-Sep-11 Dow Shield Galera 12-Sep-11 12-Dec-11 12-Dec-11 12-Mar-12 12-Mar-12 12-Jun-12 12-Jun-12 12-Sep-12 12-Sep-12 12-Dec-12 12-Dec-12 12-Mar-13 12-Mar-13 12-Jun-13 12-Jun-13 12-Sep-13 12-Sep-13 12-Dec-13 12-Dec-13 12-Mar-14 12-Mar-14 12-Jun-14 12-Jun-14 12-Sep-14 12-Sep-14 12-Dec-14 12-Dec-14 Carbetamide µg/l highlights the need to ensure good agricultural Propyzamide µg/l 0.2 0.4 0.6 0.8 1.2 1.4 1.6 0 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0 e.g. e.g. 07-Jan-08 07-Jan-08 07-Apr-08 07-Apr-08 07-Jul-08 07-Jul-08 07-Oct-08 07-Oct-08 07-Jan-09 Stoller Kerb 07-Jan-09 Crawler 07-Apr-09 07-Apr-09 07-Jul-09 07-Jul-09 07-Oct-09 Flo 07-Oct-09 07-Jan-10 Carbetamide Propyzamide 07-Jan-10 07-Apr-10 07-Apr-10 07-Jul-10 07-Jul-10 07-Oct-10 07-Oct-10 07-Jan-11 07-Jan-11 07-Apr-11 07-Apr-11 Conform 07-Jul-11 07-Jul-11 07-Oct-11 07-Oct-11 07-Jan-12 07-Jan-12 07-Apr-12 07-Apr-12 07-Jul-12 07-Jul-12 07-Oct-12 07-Oct-12 07-Jan-13 07-Jan-13 07-Apr-13 07-Apr-13 07-Jul-13 07-Jul-13 07-Oct-13 07-Oct-13 07-Jan-14 07-Jan-14 07-Apr-14 07-Apr-14 07-Jul-14 07-Jul-14 07-Oct-14 07-Oct-14 Metaldehyde through financial loss losses to prevent contamination of watercourses but ensures efficient usage of this pesticide which minimises levels of methaldehyde reaching watercourses forecast. The use of alternative products such as buffer around watercourses, maximum dosage rates and advise against application when heavy rain is disseminate best pract The Metaldehyde Stewardship Group (MSG) has launched a campaign called ‘Get it. the to remove difficult water to treat Pelletwise’ to water to caused by heavy rain or prolonged rainfall events. Pellets applied to Metaldehyde Quinmerac µg/l 0.05 0.15 0.25 0.35 0.1 0.2 0.3 0.4 0 e.g. above above the drinking water limit, so careful use is vital.