Fascine mattress

Large woven mat of brushwood used in river and coastal erosion control

A fascine mattress (Dutch: Zinkstuk, literally sink piece), is a large woven mat made of brushwood, typically willow twigs and shoots, used to protect riverbeds and other underwater surfaces from scour and erosion. They are similar in construction to a fascine, but are primarily used for hydraulic engineering works, typically to strengthen the banks of rivers and streams, as well as coastal structures like revetments and groynes.

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