## 3 Results  
The influence of turbulence in the fishway is analyzed through 3D scatterplots of mutual dependence between calculated values of [PERSON]'s shear stress (RSS) for all three planes, streamwise (\(\tau_{uw}\)), horizontal (\(\tau_{uw}\)), and vertical (\(\tau_{vw}\)). The results are given separately for each fishway configuration, combining the bottom slope (labelled i075, i100, and i125) and pool length (labelled i45, i60 and i90), while the orifice sizes pertaining to them are grouped together. The line of agreement between [PERSON]'s shear stresses on all planes (1:1:1) is shown as a reference on the scatterplots. The legend key for symbols used in all graphical representations is coded as follows: results associated with measurement planes A, B, and C are represented by squares, circles, and triangles, respectively; results associated with orifice sizes 8 \(\times\) 8 cm, 10 \(\times\) 10 cm, 12 \(\times\) 12 cm (labelled o8, o10, and o12) and vertical slot are represented by a blue, green, red, and grey color, respectively. The aim of the analyses was to determine the percentage of the flow field exceeding the injury boundary and disorientation boundary within the typical fishway pool for all tested configurations. The general flow pattern in the pools is influenced by the pool geometry and orifice/slot arrangement. In the pool-orifice (PO) type fishway, the plunging flow through the inlet orifice forms a jet parallel to the pool sidewall which, once it reaches the downstream cross-wall, is deflected towards the outlet orifice. In the rest of the pool between the main flow jet and the opposite sidewall, a considerable vortex is formed by the recirculating flow throughout the pool depth. In the vertical slot (VS) fishway, the streaming flow through the inlet slot forms a jet parallel to the pool sidewall until it exits through the outlet slot. Baffle geometry protruding from the sidewall opposite to the cross-wall forces the main flow jet to deflect from the sidewall into the pool, creating a recirculation region of low velocity on both sides of the jet. The recirculating zone within the pool is far greater than the one next to the sidewall. A fishway with the steepest bottom slope and shortest pool length (i125I45, Figure 5) is the most economical fishway, since it requires the least space for construction. For all fishway configurations, there is a visible pattern of a prevailing streamwise RSS component, in comparison to horizontal and vertical. Measured values of \(\tau_{uw}\) are on average +76% and +60% higher than concurrent \(\tau_{uw}\) and \(\tau_{vw}\), respectively, at the same measurement point for all orifice sizes in the PO fishway. Differences between RSS components in corresponding VS fishways are more notable, with \(\tau_{uw}\) being +86% and +82% higher than concurrent \(\tau_{uw}\) and \(\tau_{vw}\), respectively. There is no visible pattern of values for which \(\tau_{uw}\) and \(\tau_{vw}\) are higher than \(\tau_{uw}\) across the measured range, other than, in the PO fishway, values in the C plane are prevailing amongst those deviating from the established correlation. The same pattern is visible for the VS fishway, where \(\tau_{uv}\) and \(\tau_{vw}\) are higher than \(\tau_{uw}\) in a range \(\tau_{uw}\) < 20 N/m\({}^{2}\). Concurrent values of \(\tau_{uw}\) and \(\tau_{vw}\) are approximately of the same stress range, with differences between them ranging from \(-6\%\) to \(-13\%\) in the PO fishway and \(-2\%\) in the VS fishway, with the \(\tau_{vw}\) component being higher in all cases (\(\tau_{uv}\) < \(\tau_{vw}\)). The lowest RSS values are concentrated in the A plane for all PO fishways, not exceeding 24 N/m\({}^{2}\) on average, while the largest RSS values are concentrated in the C plane for all PO fishways, above 20 N/m\({}^{2}\) on average for all orifices, with a maximum value of 42 N/m\({}^{2}\) for \(\tau_{uw}\) under the largest orifice.