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Sediment depositions in vegetative filter strips (VFS) were studied in a laboratory flume with simulatedVFS. Results showed that VFS trapped sediment mainly through a reduction in the flow velocity andthus in the sediment transport capacity. Deposition in the VFS first took place at the entrance of the VFS,then extended down into the VFS and up to the approach channel above the VFS. The deposition ratedecreased until a steady state was reached. Changing the flow rate or sediment concentration caused anew increase or decrease in the deposition rate. Deposition efficiency of the VFS decreased as sedimentaccumulated. Flume slope and sediment size composition greatly affected the deposition efficiency.Flow rate had a minor effect on the deposition efficiency, while sediment concentration hardly affectedthe deposition efficiency. Most of the sediment deposited was larger than 150 μm in size. Over 80-90%of the sediment was deposited in the approach channel above the VFS and in the upper half of the VFS.Deposition moved downstream as the flow rate increased and the sediment size became smaller.
Sediment depositions in vegetative filter strips (VFS) were studied in a laboratory flume with simulatedVFS. Deposition in the VFS first took place at the entrance of the VFS, then extended down into the VFS and up to the approach channel above the VFS. Deposition rate of established until a steady state was reached. Changing the flow rate or sediment concentration caused a new increase or decrease in the deposition rate. VFS decreased as sedimentaccumulated. Flume slope and sediment size composition greatly affected the deposition efficiency. Flow rate had a minor effect on the deposition efficiency, while sediment concentration hardly affected the deposition efficiency. Most of the sediment deposited was larger than 150 μm in size. Over 80-90% of the sediment was deposited in the approach channel above the VFS and in the upper hal f of the VFS.Deposition moved downstream as the flow rate increased increased and the sediment size became smaller.