10 Sylvan Ln Creek Bank Erosion Protection Project (Notification of Lake or Streambed Alteration, No. EPIMS-MAN-59504-R3

The Project is limited to bank erosion protection involving biotechnical repairs. The Project will stabilize 155 feet of bank along Corte Madera Creek behind a single-family residence. The Project will dewater the work site. A mid-sized excavator will be used from the top of bank to create a temporary access ramp to a gravel bar at the toe of the bank, in the channel. The excavator will work along the length of the in-channel work area to excavate a keyway to install the buried rock, place two-ton and one-ton boulder RSP, and place boulder-anchored logs and log rootwads. Once the bank erosion protection has been installed, the Project will plant live willow (Salix sp.) cuttings within the RSP on the bank, creating a biotechnical bank erosion protection structure. The Project will remove seven riparian trees, including five California bay (Umbellularia californica) trees, one bigleaf maple (Acer macrophyllum) tree, and one non-native ficus (Ficus sp.) tree. The Project will result in a total of 2,283 square feet (140 linear feet) of temporary impacts associated with staging, access, and construction. The Project will result in 1,184 square feet (134 linear feet) of permanent impacts associated with planted RSP. The Project will result in a total of 959 square feet (134 linear feet) of habitat enhancement comprised of riparian plantings, buried live willow tree plantings, and placement of large woody debris.