Backwater valve with control linkage

A backwater valve, comprising:

• a hollow valve body having an inlet and an outlet that define a flow path;
• a valve member pivotally movable about a pivot axis between an open position in which the valve member is away from the inlet and a closed position in which the valve member directly engages and covers the inlet to prevent fluid flow through the inlet, the pivot axis being disposed above the inlet;
• a movable pressure member positioned in the hollow valve body that moves along a track adjacent to the valve member, the track extending below the pivot axis and in a linear, vertical direction that is perpendicular to the flow path, the movable pressure member moving linearly along the track between a release position above the valve member to permit pivotal movement of the valve member, and a locking position in which the pressure member intersects the flow path of the hollow valve body and is immediately adjacent to the valve member to secure the valve member in the closed position;
• and
• a manual external locking activator accessible from outside of the hollow valve body that moves the pressure member between the release position and the locking position.