![]() Experimental results show that the protective effect is more efficient when the strip length is closer to the pier and has a small diameter. Thus, the pier could be kept stable and safe by the installation of those strips. The sediment in flow might accordingly move slowly or even settle down. Our results showed that this approach slowed the flow velocity between the installed strips and bed. The length and size of the strips were chosen as factors to study their protective effect. The proposed technique can involve the use of many long strips that behave like water weeds.This paper studied a protection method against pier scour by using long strips in a submerged overfall, particularly for a pier located at the maximum depth area of overfall scour. This paper proposes a near-nature ecological technique, which can consist of a wide range of materials, to protect against pier scouring. Formation of deep scour pools by complex flow structures in bedrock‐confined rivers is the mechanism that drives incision, begging for a re‐examination of the models used to explore landscape evolution. The length of the plunging flows matches their coincident pools which are common features of bedrock rivers, explaining why these pools exist. Here we show that plunging flows get stronger during floods, which clears sediment cover that protects the underlying bedrock and increases bedrock incision potential. However, the first observations of these “plunging flows” were from relatively low discharges and it is not clear if they persist during floods. The fastest‐flows submerge toward the bed enhancing near‐bed velocities, sediment transport, and consequently the potential for bedrock incision by particle impacts. Rivers typically flow fastest near the surface and slowest near the bed, but many bedrock rivers have channel morphologies that cause this velocity/depth relation to invert. Local bedrock river incision is driven by flow structures that are not well understood. Incision in bedrock rivers sets the pace of landscape evolution by controlling the rate of geomorphic responses to climatic and tectonic signals, yet the processes driving incision occur at much finer scale than those captured by landscape evolution models. ![]() These findings have implications for flood‐hazard and aquatic habitat models that rely on modeled sediment transport driven by coarse‐temporal‐resolution climate data. Rather, spatial variability of the magnitude of the effective‐bankfull‐excess shear stress and changes in runoff due to snow accumulation and melt exert the greatest influence. Surprisingly, variation in flow rates due to differences in hillslope and channel runoff do not seem to dictate the network locations where the largest errors in predicted bedload transport capacity occur. We find that, depending on channel network location, cumulative error can range from 10% to more than two orders of magnitude. Transport capacity is determined using effective stresses and the Wilcock and Crowe (2003) equations and expressed in terms of transport capacity normalized by the bankfull value. In this study, we assume bedload transport capacity determined from a hydrograph resulting from the use of hourly (1‐hr) precipitation is a close approximation of actual transport capacity and quantify the error introduced into a network‐scale bedload transport model driven by daily precipitation at channel network locations varying from lowland pool‐riffle channels to upland colluvial channels in a watershed where snow accumulation and melt can affect runoff processes. ![]() Because sediment transport varies non‐linearly with flow rates, discharge modeled from daily total precipitation distributed evenly over 24‐hr may significantly underestimate actual bedload transport capacity. Modeled stream discharge is often used to drive sediment transport models across channel networks.
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