Leonardo da Vinci designed a canal lock to control canal water levels.
A canal lock allows boats to move between stretches of water at different elevations. Gates close a chamber around the vessel, and water is added or released until the boat reaches the level of the next section. Leonardo studied and improved lock designs while working on canal engineering in northern Italy.
His work is especially associated with the Naviglio systems around Milan. The region’s canals supported transport, irrigation, and construction, but differences in elevation made navigation difficult. Leonardo’s engineering studies examined gates, channels, and methods for managing water flow.
A canal lock is not the same as a sluice gate. A sluice controls or releases water, while a lock uses a chamber and pairs of gates to raise or lower boats. Leonardo’s contribution belongs to a long history of hydraulic engineering rather than to a single modern invention date.