In December, 1973, the Environmental Planning Division of the Department of the Environment invited proposals for preliminary studies associated with a proposed dam on the Athabasca River in the vicinity of Crooked Rapids. This study was carried out in co-operation with the Energy Resources Conservation Board and under the direction of B.C. Doell study co-ordinator. In March, 1974, the study was awarded to Thurber Consultants Ltd. who had submitted a joint proposal with Crippen Engineering Ltd. and Northwest Hydraulic Consultants Ltd. The Consultants' report was submitted in two volumes in early February, 1975. This is a summary of the Consultant’s findings. It should be noted, however, that owing to the complicated conditions at Crooked Rapids, a summary of reasonable length cannot cover all aspects of the situation. Consequently, Volume 1 of the Consultant’s report must also be read before a full appreciation of the various problems can be obtained. The Consultants were requested to carry out preliminary studies to determine the technical feasibility and estimated cost of constructing a dam in the vicinity of Crooked Rapids. The study was to encompass all engineering considerations of alternate dam alignments and heights, and was to include such items as site inspection, site mapping, hydrological and geological investigations, borrow investigation, shoreline stability problems, ice and sedimentation problems, predictable upstream and downstream effects, hydro power generation potential and potential for flood control. It was considered that the technical feasibility of constructing a dam at Crooked Rapids should be established prior to carrying out a detailed environmental assessment. Therefore this did not constitute part of the consultants assignment. The study was to assume that any dam which might be constructed at Crooked Rapids would be the first development on the rover. Consequently, the project as proposed and studies did not have the benefit of any upstream storage.