Westhouses Weir Removal
AquaUoS staff assisted The Environment Agency in exploring options for the removal or bypassing of Westhouses Weir on Alfreton Brook, Westhouses. The current structure provides a complete barrier to fish movement and also impacts natural hydromorphological processes locally that hinders the development of an appropriate morphology within the impoundment zone. Removal or bypassing of the weir would support sustainable fisheries, natural hydromorphological processes and delivery of Water Framework Directive (WFD) objectives. A ditch over the right hand bank just upstream of the weir is partly influenced by the weir and the study considered impacts to this ditch as a result of removal of the weir and other associated works. The study also considered upstream impacts linked to removal or bypassing of the weir through the former open cast site and the downstream impacts linked to any potential for sediment release. The preferred design was to fully remove the concrete weir and reinstate appropriate morphology through the former impoundment zone using riffles, pools and point bars as well as excavating the local floodplain to provide suitable floodplain connectivity that ensured flood flow bed shear stresses were controlled to an appropriate level.