b'Managing nutrients loads, water levels and wetland ecology:opportunities and sticking points in the upper Lunan Water, ScotlandVinten A1, Pohle I1, Stutter M1 and Glendell M11James Hutton Institute, Craigiebuckler, Aberdeen, Scotland, UKSince 2006, the Lunan Water catchment in Eastern Scotland, has been a focus for research and development of monitoring, modelling and mitigation methods for diffuse pollution, supportedby Sottish Government research and advisory funding as well as Agency work (ScottishEnvironment Protection Agency and Scottish Natural Heritage). It is now a priority catchment for diffuse pollution mitigation under the second cycle (2016-21) of WFD River Basin planning. Catchment issues include high groundwater nitrate concentrations, eutrophication of standing waters and associated wetlands linked to sediment, P and N loads and risks of flooding and low flows. We review progress in monitoring, modelling, management and governance of diffusepollution and water levels in the catchment. Nutrient load estimation used a combination of routine flow and water quality sampling,modelling and proxy high frequency measures such as turbidity, calibrated using storm event data. Markov switching time series analysis has helped to add value to this data. Downward trends of N and P in the main stem of the Lunan water have been identified. These may partly be due to improved sewage treatment rather than catchment-scale measures. Changes in livestock numbers are also implicated. Approaches to choosing cost-effective mitigation measures have been developed. Novel measures explored include the use of sediment fences, seeding with water cress, harvesting of aquatic vegetation and improved management of flow at hydraulic structures by diverting flow of nutrient-rich water from ecologically sensitive wetlands. Several rural payments-funded measures have been adopted, including sediment bunds, buffer strips, ponds and wetlands.Stakeholder engagement (through farmer workshops, survey, interviews and a catchmentmanagement group) has shown the additional importance of flood risk mitigation (and some concern about low flows) but governance across a range of water ecosystem services remains challenge. Potential for establishment of drainage boards or other community-interestapproaches is considered.39'