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1-Z 4. Analysis of geomorphology viewsheds, visual resource values and landscape use values to determine visual resource planning and design requirements. e 5. Use of the above data in developing the engineering aspects of project formulation. In the formulation stage, physical conditions should be determined and an appraisal should be made of other limitations imposed on channel work that might limit functional performance in meeting objectives. These include: 1. Adequacy of outlets to handle required flow without excessive scour or deposition, and without damaging downstream flooding. Z. Protection of water rights. 3. Availability of rights-of-way. 4. Satisfying minimum flow requirements. 5. Environmental considerations including landscape resources that must be conserved. Adequacy of Outlets e Basic requirements. - - In determining adequacy of outlets, the following basic requirements should be met: 1. The capacity of the outlet should be such that the design flow from its watershed can be discharged into it at an elevation equal to or less than that of the hydraulic gradeline that is used for design of the project. The storm used for this analysis should have the same chance of occurrence as the storm used for design of the improvements. Z. Where subsurface drainage is needed, the depth of the outlets should be such that subsurface drains may be discharged into it above normal low water flow. 3. The capacity of the outlet should be such that the discharge from the project watershed, after proposed improvements, will not result in stage increases that will cause significant damages below the termination of the proj ect channel. 4. Flow conditions in the outlet should be capable of maintaining equilibrium with the sediment transport of the project channel, There should not be excessive scour or deposition of sediment in the outlet. e