Figure Captions
Figure 1. Daily rainfall, daily water temperature, and hourly water level along the study reach. Upper and lower temperature limits for fish species local to Weslie Creek are labeled on the water temperature graph (LSRCA, 2000; Eakins, 2018). Field assessment days are shown with diamonds along the lower x-axis.
Figure 2. Reach profile from upstream (left) to downstream (right) with representative pool (above profile) and rock weir (below profile) cross-sections. The asterisk in the Pool 7 cross-section indicates the stilling welling location. Vertical exaggeration is 0.08 m.
Figure 3. Fish passability in low (left), intermediate (middle), and high (right) water level conditions. Rock weirs that provide 100% fish passability are represented by green keystones, rock weirs that provide fish passage for 4 or fewer fish species are represented by yellow keystones, and rock weirs that do not provide gap or over-weir flow pathways are represented by red keystones. Note that red keystones allow orifice flow and leaping opportunities for fish passage. Further, recirculation zones indicate potential locations for fish refuge during unsuitable swimming conditions.
Figure 4. Profile schematics of a low gradient rock weir (a) and high gradient rock weir (b). The difference in gradient depicts how embeddedness changes depending on how gentle or steep the channel bed is. A greater level of embeddedness provides upstream and downstream connectivity without obstructions to the flow path (b).
Figure 5. Looking upstream at VRW2 (a low gradient rock weir) under low (top photo), intermediate (middle photo), and high (bottom photo) water level conditions. It is evident that orifice flow is the only active flow regime under low water level conditions, while orifice, gap, and over-weir flow are active simultaneously under intermediate and high-water level conditions. VRW2 under low water level conditions demonstrates the importance of embeddedness for enhancing fish passage effectiveness, while VRW2 under high water level conditions demonstrates the effect of ‘drowned conditions’.