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.. Usually design criteria provides the technical criteria that would be expected to be necessary to design the control structures such as river forces, depths, velocities, flood flows, and other hydraulic parameters. The REP report includes none: of this tecrmical criteria, yet they have selected flows. Having "great play spots" is not technical criteria that can be used to develop a design. The REP Report does not provide design criteria to determine if the structures will meet the minimum flow necessary for a reasonable recreation experience nor is technical criteria described with which to design the structures for any flow. SECTION 2.B. STRUCTURE DESIGN The REP Report (pages 20 - 33) provides a general description and sketch of the "u" structures that are to be constructed in Durango's Animas River Boating Park to provide the ability to control, capture, and divert Animas River flows. The U-Structures are required to concentrate the minimum flow necessary to provide a reasonable recreation experience as the basis for the water right application. The REP Report fails to provide a design to justify that a U-Structure will only provide the minimum flow necessary for a reasonable recreation experience. The only design parameters in the REP Report concerns depth of flow calculations (page 28 to 33) but even that data is qualified by the following sentences: "One of the most important variables that is controlled is depth. The depth is described by the Weir Equation." "Note that this equation is an approximation and does not represent an exact relationship." "At this preliminary stage of the design the W'eir Equation can be used to give general indication of the shapes for the structure:s." Therefore, even for the depth of flow which is the only technical ~malysis included in the REP Report, the design is stated to be preliminary and general in natun:. The only flow parameter presented is the maximum flow of water that can be controlled of 1,400 cfs at the upper / structures (page 29) and 1,800 cfs at the lower structures (page 31), not the minimum flow necessary. The design criteria does not provide the technical information necessary to prepare a design and as a result a structure design is not provided in the REP Report but a general description of what the structures may look like. Further, based on the flexible and non-technical design criteria it appears the design of the U- Structures could be modified significantly, the flow reduced, and still provide the desired boating experience described by the design criteria. Therefore, it also appears that these structures could be designed to use much less flow than is included in the water rights application to provide the minimum flow necessary for a reasonable recreation experience.