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!l ~ 1 '7 l\ 7 Wetland Mitigation A- /8 erosion during project operations would be an indication of project effects. At bends, erosion is also expected at non-project flows, so it could be more difficult to isolate project-related erosion. The "Monitor" sites provide good locations for transects since Sponsors will have to watch them anyway. Results at these sites can be used to clearly identify when and if bank stabilization is needed in the future. Of the 22 Monitor Sites, five are located at relatively straight sections, and the balance on bends. Together with the ten supplemental sites, they should give an excellent overall picture of the river. The ten supplemental monitoring stations would be identified prior to the commencement of operations. The goal would be to spread them out geographically, and will emphasize areas containing broad flood plains with well-established wetland/riparian wildlife habitat. Site access will also be a consideration. A.5.2 Monitoring Activities. Transects would extend perpendicularly across the river channel, from flood plain edge to flood plain edge (second geomorphic surface). Cross-section endpoints would be monumented with a metal stake or concrete cap that is easily located and is protected from damage by the river or other activities. River profile would then be surveyed using a tag line and differential level, or similar procedure. The river flow and mid-channel velocity as well as approximate bedload estimates would be noted during monitoring visits, and visual inspections for recent erosion evidence would be made. Increases and decreases in the width of the riparian corridor will be noted. The river cross-section would then be plotted and compared to previous results at the same location. From these efforts, changes in river width, aggradation and degradation can all be identified. If active erosion threatens terraces (particularly at "Monitor Sites"), then this would potentially trigger activation of the site. See Section 2 of the 404 Application, and Section XI-A of the Final Report on Bank Stabilization for additional information on potential activation of Monitor Sites. A.5.3 Schedule. Initial transect development and profile creation would take place before commencement of project operation. After that, cross-sections can be monitored and re-surveyed once per year. Sponsors recommend that the monitoring occur during the late summer or early fall, as this would coincide with transect fieldwork under the Wetlands Monitoring Plan. This is also usually the time of lowest flows, making in-channel survey work safest. In addition to monitoring cross-sections on a regular, annual basis, Sponsors propose to field-inspect the "Monitor" sites after significant floods, and monthly during the first season of project operation. Landowner communication will also be important. If a bank is eroding into a cultivated field, the farmer is probably going to be the first one to know. ~~ AS Lateral Hydropower Project JVly 21100 1. :,L~::<~ Ji}...,,,.,';.,",,,<~i~ "