Abstraction point prefabrication ensures accuracy of fabrication to provide for accurate HOF and share weirs.
The fabricated Weir box(s) may be easily installed alongside or into the river bed using small quantities of dry mix concrete minimizing the risk of pollution, shortening the working time in the river bed avoiding flooding and general access damage to the surrounding ecology.
The screen arrangements may be made more accurately to ft more closely where Elver screens are required at 2/3 mm gaps only
Mechanical screen cleaning techniques whether using rakes or sluice gates and reverse flow techniques become complex devises requiring accurate detailed manufacture easy to achieve in a workshop prefabrication environment.
Fabrication using Corten Steel provides a natural colouring to blend into the surroundings with minimal concrete visible. Corten is mainly used as bridge steel as it corrodes to a skin depth and then stops avoiding painting and other anticorrosion methods. It is lower cost than stainless steel.