Fascine mattresses (Classic)
Fascine mattresses without synthetic fabric
A classic fascine mattress is made exclusively from bundles of willow branches (known as faggots). First of all, a framework of faggots is constructed: one faggot every metre for the first layer, and then a second layer at right angles to the first. Each intersection is secured with lashing rope, which also forms the basis for further securing the brushwood on the fascine mattress. The rope contains sisal-polypropylene which tightens when wet. The brushwood bundles are evenly distributed between the top layer of faggots to a thickness of 10 to 15 cm. A second layer of brushwood is placed on top of these, at right angles to the first layer. The customer determines the thickness of the faggots and the layer of brushwood. The customer could be: Rijkswaterstaat (Directorate-General for Public Works and Water Management), a municipality or a contractor. A classic fascine mattress is more labour intensive because it is made purely from willow, without the incorporation of synthetic fabrics. It is therefore much more environmentally friendly than the contemporary fascine mattresses made from synthetic fabrics. Van Aalsburg is therefore putting more and more classic fascine mattresses together: the new trend. Per day 3,000 m2 and per year an average of 1,000,000 m2. In the Netherlands, Latvia, the United Kingdom, Germany, Denmark and Belgium. And even in Surinam and Aruba.
Preparation of the sinking on the ‘zate’
The ‘zate’ is the place alongside the water where the fascine mattresses are made. They are often enormously heavy and big and are approximately 50 cm high. They are made on pipes, which makes them supple and enables them to slide smoothly and undamaged into the water. The zate must be accessible by truck and a crane must be able to drive on it because a great deal of willow has to be transported there.
It may be that an extra layer of faggots has to be tied onto the mattress to prevent the basalt rocks from rolling off it during the sinking. This extra layer is just as effective, but less expensive than the willow wickerwork that was formerly attached to the top of the fascine mattress.