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The bar graph is ftom Appendix C, page 7 of the engineer's report. It shows huge spikes of Total Suspended Solids at various locations 0J:l the creek in 2004 from minor maintenance done in early 2004. This is clearly not good. With options 1 and 4 would this would occur for the foreseeable futw'e. This is not good. Option 2 is likely unstable and the numerous other disadvantages are in the report. The best option is to stabilize the stream as explained by Dr. Sandy Verry and the engineers and then, virtua1ly no maintenance of that sort is required. The channel becomes a self cleaning natural system to the best known scientific research. (Note: Side conversations indicate there may be a current problem with snowmobile crossings in winter blocking the creek in spring. Perhaps bridges need to be constructed or snowmobile trails moved where they will not cause a problem.) The below describes Option 3 and is trom page 30 of the engineer's report. "STABLE STREAM REHABILITATION Drainage ditch construction often occurs without taking stream morphology into consideration. Most notably, ditches often lack: a meander pattern and a two-stage relationship between a main channel and a floodplain. The Stable Stream Rehabilitation alternative would create a properly sized meandered base channel lower than the existing channel, a connected and properly sized floodplain also lower than the existing floodplain, and a stable meander pattern. Figure 7 shows a cross-section of this alternative. Figure 7. Stable StreaID RehabDitatiOD Cross-seetioD UlWBlEDflOODIIUlIN 5lIIIiE IIEllllOWIlE5RlIWIOllI AI'PllGI.llII' ~ "'--~~~~ APPIlIIlLtlr MEMDElIDOWNL --'e-~~~-~/ "--- ~~~-- " :..----- - '-~ This design is based on stream morphology principles in order to establish equilibrium between the stream channel and the external forces shaping the channel, leading to a stable channel configuration. Field verified b3n1cfitll conditions were used to calculate design parameters. Dr. Sandy Verry, a peatland drainage and stream restoration expert, was contacted to provide design input. Dr. Verry recommended that a new channel be created off of the existing ditch and allowed to stabilize for one growing season before ditch flows are diverted. The reasons for this are: · Reduced risk: of c~el block failW'eS · More stable peat for construction as verified through the von Post analysis · Easier constructability without active ditch flows · Significantly less water quality impact both during construction and long-term Related to this alternative is the restoration of the Hardwood Creek corridor (Appendix 11). This initiative is in accordance with the District goals of land and water conservation and wetlands management. The District sought partnership in applying these goals to JD2 and was awarded a grant by the Legislative Commission on Minne-nta Resources (LCMR) of$800,OOO for the purpose of creating a restored riparian corridor.