Efficiency of drone technology for lake water sampling: is it better than traditional boat methodology?

Water pollution is one of the main socio-environmental issues in recent decades, affecting humans and various species. The increasing use of drones can be an alternative that helps more easily monitor the status of hard-to-reach water bodies, making their examination more accurate and allowing for the implementation of appropriate restoration measures. In this study, we investigated the use of drones to monitor three small shallow lakes in Ireland, an island with hundreds of lakes. The objective of this study is to compare the drone sampling methodology versus the traditional boat-based methodology, evaluating aspects such as the reliability of the results and cost-effectiveness. Key physicochemical water parameters such as total phosphorus, chlorophyll a, dissolved oxygen and pH were measured over a three-month period using multiparameter probes and water sample collection. Both methodologies yielded identical results for nine of the ten measured variables. In turn, the drone method, while entailing higher initial fixed costs, ends up being not only faster but also more economical in the medium and long term, also representing a safer and more far-reaching sampling alternative than the boat methodology.