“Unknown canal” December 2016. Colmar. France. Canals and navigations are human-made channels for water conveyance or to service water transport vehicles. In the vernacular, both are referred to as 'canals', and in most cases, the engineered works will have a series of dams and locks that create areas of low speed current flow. These areas are referred to as 'slack water levels', often just called 'levels'.
Gloss or Mat