A waste disposal system includes a receptacle with a base adapted to receive a waste tray assembly on a top panel thereof. The top panel includes an inlet drain opening. A discharge drain is provided in the receptacle base. The waste tray assembly can include natural or artificial turf, and is removable from the top panel. A cover can be mounted on the receptacle base and can be movable between open and closed positions. Alternatively, a lid can be provided for removably mounting on the receptacle base.