Little Mill Creek Groundwater Recharge Incised Channel Repair Project (Project) (Notification of Lake or Streambed Alteration, No. EPIMS-MEN-64381-R1C)

The California Department of Fish and Wildlife has executed Lake and Streambed Alteration Agreement EPIMS Notification No. EPIMS-MEN-64381-R1C, pursuant to Section 1602 of the Fish and Game Code to Nicole Schmidt representing The Nature Conservancy. The Project is part of the Navarro River – Mill Creek Habitat Enhancement Project and is limited to one (1) encroachment to conduct restoration work within approximately 600 linear feet of an unnamed tributary to Little Mill creek to increase groundwater recharge and augment dry season stream flow in the Mill Creek watershed. Work for this encroachment will include excavation, placement of fill, log sill and rock grade structures into the channel, removal of an existing culvert and replacement with a seasonal rocked ford crossing, removal, relocation, and replacement of an existing culvert, revegetation plantings, backfilling and compaction of fill, and rock armoring as necessary to minimize erosion. Rock Grade Control and Log Sill Structures. The project will install rock grade control and log sill structures and place soil into the incised channel to develop a series of low gradient reaches and pools. Soil will be placed in the stream to raise the channel bed to the same elevation as the floodplain benches. The rock structures will be installed in the steeper stream reaches and will include a clay barrier on the upstream side to minimize water leakage through the structure and maximize upstream water retention. Two felled redwood trees (30-inch and 40-inch diameter at breast height [dbh]) will be cut into lengths to create the log sill structures, which will also incorporate the trees’ root wads. Culvert Removal and Installation of Rock Ford Crossing. An existing 36-inch diameter corrugated metal pipe (CMP) culvert on the downstream end of the project site will be removed and replaced with a rocked stream crossing. The rocked crossing will accommodate a 12-foot road width and will include the placement of one-ton rock on the downstream side to create an energy dissipation pool to reduce erosion. Vehicles shall not be operated on the ford crossing when surface water is present. Culvert Relocation. An existing 18-inch diameter CMP culvert that conveys flow to the stream from the access road will be removed, replaced, and relocated to discharge upstream of a log sill structure. The outfall will be rocked to reduce erosion in the channel. Revegetation and Erosion Control. Revegetation includes ten (10) one-gallon redwood plantings, 92 native shrub plantings, 1,712 sedges and rushes plantings, 306 forbs and ferns, and 400 grass plugs.. Erosion control treatments include installation of 17,640 square feet of coir blanket and native plant seed mix.