 When the canal was built, it was made quite wide, and the locks were all constructed on the northern side of the canal, rather than centrally to the channel, as most locks built previously on the BCN had been.This was probably to make the task of duplicating them easier, if this became necessary.This arrangement created a large lagoon on the southern side of the lock, at the end of which a simple cascade weir allowed surplus water to flow into the next pound.