Filling and discharging system

A filling and discharging system is the hydraulic arrangement that fills and empties a navigation lock chamber, sized to level it against the head between the two pools quickly without dangerous currents on the moored ships. Small locks use gate sluices or wall ports; large locks use longitudinal or transverse culverts through the lock walls and floor, fed through valves and distributed by ports to spread inflow across the chamber footprint. Design targets filling times of several minutes for the chamber volume while keeping hawser forces on a berthed vessel within the limit, often a few tenths of one percent of displacement, set by PIANC lock guidance. Energy-saving locks add side basins to recover water.