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III. Identify channel avulsion using LiDAR, and develop preliminary hypothesis about possible triggers. IV. Calculate meandering planform statistics for different reaches of the Red River of the North, Rush, Lower Rush, Maple, and Sheyenne Rivers and compare bankfull geometry and streamwise slope for bracketing of the proposed planform and cross section configuration of the LFC. V. Develop RVR Meander models for selected reaches of the Red River of the North, Rush, Lower Rush, Maple, and Sheyenne Rivers to obtain calibration parameters for evaluation of the proposed planform and cross section configuration of the LFC. VI. Quantify the ultimate meander amplitude of the proposed planform configuration of the LFC using RVR Meander in probabilistic fashion to account for the observed variability in hydrologic conditions and soil properties. VII. Provide most optimal, alternative planform and cross section configuration of the LFC that minimizes meandering adjustments in both the short- and long-term. Evaluate need for lateral and vertical erosion control features in the LFC or the main diversion channel. VIII. Assess impact of different scenarios for commissioning of diversion works on short-term LFC meandering adjustments using RVR meander in deterministic fashion. IX. Develop a summary of significant O&M activities for the West Fargo Diversion and Horace to West Fargo Diversion Channels. This will include a map for every year since the Diversion channels were constructed, including items such as quantities and lengths of sediment removal, riprap, structure installations or modifications, or surveys. X. Provide technical assistance and review to USACE on sediment transport analysis and Geomorphology Study. The following data and definitions will be provided by USACE or Owner: I. The resistance to erosion and shear strength properties of the soils along the LFC, including ongoing laboratory tests of soil erodibility at Texas A&M, as well as more recent geotechnical field investigations conducted along the LFC and main diversion channel. II. The proposed LFC dimensions (cross sections, slope) and planform configuration. III. Design flow discharges for the LFC, including updates on the hydrology of frequent events. IV. Proposed vegetation coverage at the bottom of the main diversion channel. V. Report prepared by WEST Consultants (“Geomorphology Study of the Fargo, ND & Moorhead, MN Flood Risk Management Project”), including electronic files containing historical data compiled and new data collected. VI. Most likely scenarios for commissioning of diversion works. Prepare a first Draft Technical Memorandum: I. Summarize key findings during initial site visit. II. Describe field investigations along successive point bars in meander loops; include laboratory results of carbon dating, if available. III. Identify channel avulsion areas, and of other geomorphic features (e.g., oxbows) characterizing river dynamics over long spatial and time scales. HMG_TO08-A10_Long.docx 2 DR A F T