San Anselmo Creek Bank Stabilization Project

San Anselmo Creek Bank Stabilization Project

The proposed project includes a live willow pole vegetated 1/4-ton, 3-ft thick rock rip-rap bank extending from below the water line (min 3-ft below the adjacent min channel bed elevation) to approximately 9 ft above the water surface to min elevation 111 ft at max finished face slope 1(H):1(V). The rip-rap bank will be designed and constructed to avoid damaging the existing intact remnant of the former toe of bank that contains native riparian trees and roots. The exposed toe of the bank in this intact section will be heavily planted with live willow poles to improve its stability. The toe of the bank on the gravel bar would be planted with native alder 1-gal container plants (not less than 4). The upper bank from the top of the proposed rip-rap bank to the landscaped private residential area at approximately elevation 118 ft is to be stabilized by laying back the bank to maximum stable slope 1.5(H):1(V) using grading and mechanically stabilized earth (MSE) soil lifts if and where minimum fill may be necessary, and covering the finished native soil slope with biodegradable erosion control fabric, planting with native shrub and tree 1 gal container plants (not less than 1 per 40 sq ft plan area, and establishing a drip irrigation system to irrigate upper bank plantings). The applicant expects to be able to perform all construction from top of bank, not entering the stream channel or de-watering an area within the vicinity of the project. Issuance of a Streambed Alteration Agreement Number 1600-2006-0630-3 is pursuant to Fish and Game Code Section 1602.

Fairfax

Marin