Extractors work by removing the sediment laden bottom layer of flow in a canal.
They are usually located in canal head reaches, where additional water is available to operate the extractor, and there is sufficient head to transport the extracted sediment back to the river. Extractor design - determines the leading dimensions of an extractor to ensure that it does not block with sediment, and operates with an acceptable head loss. Trapping efficiency - calculates the trapping efficiency of a sediment extractor. This is the proportion of sediment in the flow that is removed, and is a measure of the performance of an extractor design. Extractor location - determines optimum extractor location.