The Tunnel Stabilization & Sewer Pipeline Replacement Project has undergone a rigorous, years-long environmental review, planning, and design process. The following are the major milestones of the project's environmental review, regulatory approvals, and construction preparation.
- The District’s Board of Directors approved a comprehensive Environmental Impact Report (EIR) in 2010.
- The District conducted a design constructability review between 2010 and 2012 to select the best options for construction of the project.
- The District obtained 194 easements from area property owners needed to carry out the project.
- The District worked cooperatively with the City of Laguna Beach through the representatives to the South Laguna Water and Sewer Advisory Committee to inform and reach consensus decisions on the project.
- From 2008–2014, the District held more than 30 public outreach meetings with various community groups and organizations and a project update was provided at more than 100 South Coast Water District Engineering & Operations Committee and Board of Directors meetings.
- On December 11, 2013, the City of Laguna Beach approved the project within its jurisdiction.
- The District obtained the required permit from the California Coastal Commission in May 2016.
- Work began at the shaft site located at Coast Highway and 4th Avenue on March 6, 2017.