Mill Creek Reconnect- Pahsimeroi

Project Narrative

Originally the Mill Creek channel was eliminated and dewatered by the interception of the entire Mill Creek flow by the Big Creek 3-BC3 ditch/diversion. Mill Creek was reconnected with Big Creek through new channel excavation and the installation of approximately 300 feet of buried pipeline and 6 lateral pipe (to provide irrigation to a lower field) was completed. The buried pipe will convey Big Creek #3 ditch under the newly constructed Mill Creek and allow the delivery of and maintain 1.8 cfs in Mill Creek as it enters into Big Creek. Approximately 0.51 miles of new stream was constructed, 77 instream structures were placed in the new channel, and 17 pools were excavated. Approximately 0.16 miles of existing stream was treated for bank stabilization on both sides of the stream (0.32 miles of streambank) with 38 structures and 6 pools were excavated. The total stream treated was 0.67 miles, a total of 23 pools were excavated. There were no pools created as a result of scour through the placement of the structures. A total of 1.39 acres and 0.73 miles (both sides) of stream bank of riparian habitat was planted with native plants and grasses. Upland area acres (1.17) were planted with upland grass seed and .2 miles of the unused two-track road on BLM property were abandoned, decommissioned and reseeded. Historically, elk frequents this worksite area, so a temporary eight-foot high, square wired fence was installed to protect the both sides of the constructed channel portion of the project and the entire riparian and upland treatment areas. This is a temporary fence that will be maintained for 3 to 5 years before it is removed to ensure that the riparian and upland area treatments take hold and become established. To clarify, Riparian treatment acres = 1.39, Upland treatment area = 1.17, untreated acres within the enclosure = 2.23 for a total of 5.1 acres. Eight (originally proposed as 1) sediment control (earthen plugs) were placed at various locations along the treated channel to prevent high flows from being captured from Mill Creek. These plugs were placed in non-permitted lateral ditches on BLM property that were used by past landowners, and 2 ditch plugs on ditches that are no longer used on landowner property. During the project there were some deviations regarding fish passage. It was originally proposed that fish passage issues were going to be resolved through the removal of debris and installation of a hardened crossing. The removal of the debris was prep work for instream project actions. The hardened crossing was part of the design work for instream work to allow the landowner to access his property when flow was put back in the channel. Neither of these originally proposed metrics were related to a fish passage issue. Therefore, the actual fish passage metrics indicate zero on the database. Since all of this work was actually pre work for instream habitat the funding has been moved to instream work. Another deviation was the proposed site maintenance. It was determined early in the project site maintenance was an incorrect proposed metric, and was removed from the database at that time. Site maintenance projects are specific to going back to a previously project that many have some failures and address only that maintenance.