Option 1: Full Weir Removal Only
Full weir removal is on top of the hierarchy of suitable solutions to improve fish passage along the river systems.
Option 2: Full Weir Removal with Pre-Barrages / Step-Pools
Further down the hierarchy of suitable solutions to improve fish passage along river systems, Option 2 would consist of completely removing one or both weirs associated with Shepley Mill.
Option 3: Full Weir Removal & Rock Ramps within the Carshalton & Croydon Branches
This option consists of either removing one or both weirs associated with Shepley Mill, desilting, regrading the bed, constructing rock ramps within the Carshalton and Croydon branches of the River Wandle to improve fish passage; and installing
Option 4: Weir Lowering & Rock Weirs within the Carshalton & Croydon Branches
This option which was originally put forward by CBEC Eco Engineering to improve fish passage and river habitat at Shepley Mill, consists of lowering the west weir by 1 m and constructing two fixed head rock weir/ramp structures on the Carshalton and
Option 5: Technical Larinier Fish Pass on West Weir
This option would consist of a technical fish pass (with super-active baffles i.e. Larinier) installed on the west weir, which as stated takes the dominant river flow with the entrance to its downstream culvert providing the greatest ‘lead’ for
Option 6: Technical Larinier Fish Pass or Baffles/Pre-Barrage on East Weir
This option would consist of either installing a low cost technical fish pass, such as a Larinier; or a low cost baffle (pre-barrage) fish pass on the east weir to improve fish passage.
Option 7: Cylindrical Bristle Clusters on West or East Weir
This option would consist of fixing Cylindrical Bristle Clusters (CBCs) on a constructed concrete ramp within either the west or east weir.