Lock channel
From BAWiki
Definition
Section of an impounded river usually as an external arm that branches off from the river as an access to the ship lock system. The upper and lower lock channel completely or partially forms the upper / lower part of the outer lock harbor as part of the lock installation. A lock channel can simultaneously be a power plant (eg. lock channel Gerlachshausen of the Main river, lock and power plant channel Wieblingen of the Neckar river). When building a new lock channel, the former, if it remains for traffic, becomes the old lock channel; if the lock is taken out of service, it turns into a former sluice channel.