Evidence review of water quality for NVZ assessment

Background The Nitrates Directive (91/676/EEC) aims to protect water quality by preventing nitrogenous compounds from agricultural sources polluting ground and surface waters and by promoting the use of good farming practices. The EA is required under the terms of this Directive to identify waters which are or could become polluted by nitrogenous compounds and to designate these waters and all land draining to them as Nitrate Vulnerable Zones (NVZs). Farmers in designated areas must follow an Action Programme to reduce pollution from agricultural sources of nitrogenous compounds. The regulations require the EA to undertake a review every 4 years and make a recommendation on the NVZ designations for England. The next NVZ period is 1st January 2025 to 31 December 2028, the recommendation is due in 2024. There are 3 elements to this project, this contract is for parts 1) and 2) below; 1. determine what water quality monitoring data is available to inform the next NVZ Review and provide a high-level summary of that data (as well as key contextual data on water quality risks) 2. undertake a high-level assessment of whether the risk from nitrate pollution has changed (in scale and/or extent) between the previous and current Review Periods For information only, potential for part (3) to be commissioned at a later date when results from (1) and (2) above have been assessed: 3. critically assess whether the available data are adequate to apply the existing NVZ Review methodology robustly for the current NVZ Review period (2021-2024) and make detailed recommendations for any changes required to the methodology or for developing and implementing an alternative approach, if necessary. The contract scope is limited to English 'surface waters' (i.e. rivers) and groundwater.