The anti-eutrophication protection of lakes requires limiting the inflow of nutrients to the water bodies and restraining the growth of algae and plankton. One of the ways to limit the size of algae populations in a lake is to maintain within the surface layer of water the flow conditions that are unfavourable for their growth. With this in view, it was proposed to install an aerator on the Zdworskie Lake (Gostyńsko-Włocławskie Lake District) to ensure a constant waving surface flow. The lake has been provided with barriers against the expansion of algae, and measures have been taken to prevent the water level from lowering and to limit the inflow of biogenic substances. The role of the aerator is to distribute water coming into the lake from the Dobrzyków pump station while maintaining a waving surface flow. Laboratory tests of the aerator were aimed at investigating the influence of diverse hydraulic conditions of the lake on the effectiveness of the device. This influence was modelled by changing the deflection angle of the aerator shield and varying its height and location against the water table.

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