Use of Vegetation and Natural Materials
Sankey Natural Flood Management Initiative Sankey Valley, St. Helens, England, United Kingdom A series of Natural Flood Management (NFM) strategies were implemented in 2012 in the Sankey Valley in Northwest England. The NFM initiative was spearheaded by St. Helens Council but was ultimately embraced by the broad partnership of organizations that comprise The Mersey Forest. A monitoring study conducted by the Universities of Liverpool and Newcastle found that four engineered log jams—commonly referred to as “leaky dams,” constructed by Groundwork Charity as part of the initiative—improved water quality, trapped sediment, and attenuated floodwater in the catchments. The water attenuation, in particular, contributes in a small way to the protection of Blackbrook, a downstream community that has flooded three times since 2000, with a 5 percent chance of flooding in any given year. The Environment Agency of England (EA) then led three environmental outcome days, building seven more leaky dams. The initiative was profiled by the EA in the Working with Natural Processes-Evidence Directory; by Economics for the Environment (Eftec) consultants and the Green Alliance in their Natural Infrastructure Schemes in Practice publication; and by the Institution of Civil Engineers, in an engineering sustainability-themed paper.
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