CLICK THE VIDEO LINK HERE: http://www.youtube.com/watch?v=cLeepRYGP80
When banks are being lost at a rate of around one metre per storm event along miles of riverbank (like here on the river Manifold), terrestrial and aquatic flora and fauna are badly impacted
Brashings can be used to slow down runaway erosion and collapse of riverbanks
It is important to highlight that erosion is a vital ecological process - but can run out of control in grazed systems. In such instances, extensive regular bank loss leads to significant reductions in habitat quality for a wide range of aquatic and terrestrial species of flora and fauna. Attempts to stop erosion dead in its tracks using "Hard" revetments of blocks of stone or gabion baskets often create more problems than they solve (due to eddying currents arising from their relatively smooth, geometrically angular surfaces). Fast linear flow and whirling vortices that are both promoted by "hard" engineering result in flashier river flows and higher potential for destructive erosion. Brashings are an ideal alternative due to their very high surface area to volume ratio (hydrologically, they are much "rougher" than hard engineering). This has the effect of "stilling" or damping out fast flowing water currents next to the bank, accumulating sediment, regrading the vertical bank faces to a more shallow incline and (in combination with managed livestock access) allowing marginal vegetation to grow up and consolidate the new bank. The branches also provide habitat in their own right for a range of invertebrate and vertebrate species (including juvenile trout and kingfishers as notable, linked, examples).