Photo: High standard of weir and dropshaft construction under scrutiny
Part of WRG North West team help build the base to Lock 25 bywash in May 2009
A bywash forms an overflow by diverting surplus water over a weir instead of allowing it to flow over the lock gates. It then flows via a small tunnel into the lower lock.
An unusual circular design has been used to make it a distinctive feature of this canal in future. A footpath around it to the best disability access standard will cross a small bridge over the spillway.