Summary of Monitoring and Research at Cottonwood Ranch

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subset of the intensive monitoring and research sections were resurveyed and bed material resampled at these sections. These resurveys included 2 sections in the Input reach, 3 in the Managed, and 3 in the Output reach. These resurveys and samples are intended to document natural intra-year variability in bed elevation and bed-material grain size. The General Monitoring component was also completed at this time. A total of 5 additional cross-sections that traverse the entire width of the Platte River (include all channels) were established. While all of these sections are located downstream of the intensive research reaches, 3 are located upstream of the Elm Creek Bridge and 2 below the bridge (Figure 2). The sections located downstream of the Elm Creek Bridge were placed on NPPD property and thus did not require special permissions for access. However, the three sections above the Elm Creek Bridge were located on private property whose ownership required significant research to ascertain. These landowners ultimately granted permission to access their property. The General Monitoring transects were surveyed and sampled in approximately the same manner as the intensive sections described above. Survey lines for the General sections were pre-selected in the office with GIS software and the endpoints of these lines entered into the GPS data collector. The endpoints of these lines were navigated to in the field and the section monumented and surveyed in the same manner as the intensive sections. While the total number of bed material samples collected in the General Monitoring transects is similar to the number collected in the intensive sections, 10- 15 verticals, the sampling was not as intensive as a whole along the sections with multiple channels. A minimum of three or four bed material samples were taken at equal intervals across each of the North and South channels. It was decided that the center channel would be sampled with greater intensity than the both the North and South channels because a larger proportion of the flow is conveyed through this channel. We took ground photographs from the left bank of the river to the right bank in a manner similar to that described above for the intensive sections. C. Summer - 2001-(Surveying, Sampling, and Photography --- Temporal Sections) On July 22, 2001 we revisited the same subset of intensive monitoring sections as were resurveyed and resampled in May. The extent of management activity that was planned to occur along the large island between the Managed and Output reaches was somewhat uncertain at the time of the monitoring plan design. Prior to this field trip it became clear that significant management action, clearing or perhaps leveling, is planned to occur on the large island. We decided that monitoring in the Managed reach should be extended to include a number of cross-sections that traverse this large island. An additional 17 cross-sections were established in this region between the Managed and Output reaches. These sections broaden the spatial extent of the monitoring and have the added benefit of connecting the Managed and Output reaches. With this increased level of detail it is now possible to better utilize flow and sediment transport models to route water and sediment between the Managed and Output reaches. These additional sections will be resurveyed a minimum of once a