In 2012 The Canal and River Trust were seeking a restoration solution for a vertical edged section of the Grand Union Canal. Permission to remove the edging or carry out in stream civil works had been declined due to the inherent flood risk and any reduction in the channels capacity.
Vertical hard edges are now common feature in waterway sections that flow through or near urban locations. As a solution CRT selected a series of Floating Edge Ecosystem modules on the basis of price and quality, as the best solution to provide bank protection and habitat to restore the river’s edge without obstructing flow or navigability.
Part of the planned works included restoration to the main pond and surrounding area, the first step was to drain and desilt the pond, overtime it had lost its capacity due to heavy silting. Next new stone walls were built all-around the lakes banks, and the surrounding slopes were landscaped to provide grassed areas leading up to the water’s edge. Stone pathways were installed, and original features were in reinstalled on monuments along its surrounding walkways.
The most cost-effective method for this particular project was to use a Tencate Geotube® Dewatering System, this being the most cost effective and simple solution to de-sludge / dewater the lagoon’s difficult wet waste material(Iron Sludge). Anglian Water’s Biosolids team have been keen to find innovative solutions to dredge and dewater Iron sludge’s, reduce volumes, retain and reuse silts for their Biosolids operation, at significant reduced cost.
The London Borough of Havering consulted with the Environment Agency in order to improve the characteristics of the river over a 1.8 kilometre reach, thereby improving habitat for the local water vole colony and other aquatic species.
Improvement works included construction of in-channel berms using faggots, flow deflectors utilising felled timbers, creation of backwater ponds, re-grading of bed levels to create shelves and islands.