Predicting Epipelic Algae Transport in Open Channels: A Flume Study to Quantify Transport Capacity and Guide Flow Management

Abstract

The functionality of rivers and open diversion channels can be severely impacted when the epipelic algae group that grows on concrete inclined side walls, which are typical of urban rivers, joins the water flow. This study aims to increase the long-distance transport of epipelic algae groups in urban rivers and open diversion channels through flow scheduling and to anticipate their transport capacity with respect to water flow. Current research on contaminant movement is primarily based on mathematical models with limited data on flake epipelic algae types. A sidewall epipelic algae group in a flume was modeled using a generalized hydrodynamic experimental approach. Hydraulic experiments were conducted to study the physical movement form and transport capacity of the suspended epipelic algae group. This study suggests that the epipelic algae group will create transport movement without sedimentation when the velocity reaches 80–85% of the main flow velocity and settle to the bottom when it falls below 80%. This research can support the mathematical modelling of hydrodynamic transport, provide a research foundation for long-distance transport, and estimate potential gathering places and sediment amounts under different water flow conditions.