A canal pound is the stretch of level water impounded between two canal locks. Canal pounds can vary in length from the non-existent, where two or more immediately adjacent locks form a lock staircase, to many miles.

A specific type of canal pound is the summit pound, which is formed at a summit on the canal, and where both the defining locks descend from the summit pounds. Summit pounds are particularly important in canal design, as every boat entering or leaving the pound results in a loss of water. Summit pounds therefore need an independent form of water supply, which may take the form of weirs on adjacent rivers, reservoirs or pumping stations.