<p>Piano key weirs (PKWs) are a new, nonlinear form of labyrinth weir known for their high hydraulic efficiency. Investigating local scour and developing solutions to mitigate it for these weirs is of significant importance. In the present research, for the first time and to the best of our knowledge, edged steps were implemented in the outlet keys of a Type B trapezoidal PKW. The PKW model used had a height of 0.20&#xa0;m and consisted of three cycles. The steps, configured in sets of four per outlet key, were installed with three different edge heights and two different longitudinal positions within each key. Edged steps direct the flow and maximum scour depth further away from the weir toe. The edges act as a barrier, reducing the flow velocity exiting the outlet keys. By relocating the maximum scour to a greater distance from the weir toe, the risk of structural undermining is lessened. As the edge height increases, the maximum scour depth decreases, and its location moves farther downstream. The presence of edges at the end of the steps contributes significantly to scour reduction. Edged steps showed better performance in reducing scour compared to un-edged weirs. Furthermore, the maximum scour depth decreases with a reduction in the densimetric Froude number, which is achieved by lowering the flow discharge or increasing the tailwater depth. In the present study, the densimetric Froude number ranged from 0.437 to 0.887. Finally, dimensional analysis and gene expression programming (GEP) were employed to derive predictive equations for the maximum scour depth and its corresponding distance from the weir toe.</p>