A modular belt constructed of belt modules having a large open area, making the belt suitable for use as a traveling water screen. The modules include an intermediate portion composed of intersecting sets of link elements and transverse elements that form a gridlike pattern. Openings bounded by the walls of consecutive link elements and transverse elements form channels through the belt for the flow of water. The modules are connected together by hinge rods to form a belt that can be used as a water screen. Detachable flights or scoops for lifting debris or fish out of a stream are attachableto base modules.