Section 401 Water Quality Certification Public Notice
Cascade Drive Box Culvert and Retaining Wall Repair Project
The San Francisco Regional Water Quality Control Board is currently reviewing an application for the following project for water quality certification under Section 401 of the Clean Water Act. We encourage public comments on the proposed work, which will be considered in the decision on certification. You may submit comments on this project to the staff member below.
| Project Name: |
Cascade Drive Box Culvert and Retaining Wall Repair Project |
| City/County: |
Mill Valley, Marin County |
| Comment Period: |
11/27/2024 - 12/17/2024 |
| Project Description: |
The project includes repairs to a retaining wall and a concrete box culvert. The box culvert has been undermined over time and the ground may no longer be supporting the bottom (invert) slab of the culvert or the culvert verticals. The retaining wall runs along the western bank of Old Mill Creek downstream of the box culvert for approximately 70 feet. The retaining wall is constructed of concrete pile lagging stacked horizontally and wood soldier piles, with the latter showing extensive decay. The decay of supporting soldier piles could result in failure of the retaining wall. These conditions must be addressed before either fails, leading to potential impacts to Old Mill Creek and/or loss of access by residents along Cascade Drive. |
| Project Files: |
Contact Staff for files |
| Staff Contact: |
Christina Toms (510) 622-2506 Water Quality Control Board 1515 Clay Street, Ste 1400 Oakland, CA 94612 |
