This report describes the design and operation of models I, II, and V. No report has been prepared on model III - the differences in design between it and model II were not great enough to warrant a separate report. Models IV and VI have been tested, and reports describing their features and operation are being prepared. The basic design for model I was taken from that developed by the Fisheries Research Board of Canada during an investigation with traveling cables and a chain. BCF experiments on model I indicated a need to eliminate the drag created by the screen as it returned upstream through the water. This change was accomplished in model II by raising the screen clear of the water on its return upstream. Model III, installed and tested within the Maxwell Canal (Hermiston, Oreg.) during 1966, had some improvements over model II, particularly in design of the carriage, track, and drive systems. The step from model III to IV was significant from the standpoint of design and size of structure - the carriage and track systems were drastically changed, and the screen had to be made larger and stronger to handle flows that were 10 times greater than those handled by model III. Model V represented a complete change in design and incorporated such features as a cable-suspension support structure, cantilevered screen panels to resist water forces, and replaceable panels in lieu of continuous screen belting.