South Shore Breakwater - North Section

The South Shore Breakwater serves as a near-shore structure that protects the shoreline and coastal assets along Cupertino, South Shore, and Bay View Parks. The existing stone on the north section of the breakwater is undersized for the forces that are applied from storm events and ice. Over the years the existing stones have been moved due to these forces flattening the breakwater and developing gaps. The last investments related to the construction of the breakwater took place in 2006, and the condition of the asset has deteriorated over time. Age, high water, and wave action have resulted in numerous openings in the breakwater, and a large stone that had made up the structure has been moved into the navigation channel that is adjacent. Significant investments have been made to the Oak Leaf Trail, South Shore Yacht Club, South Shore Boat Launch, and related assets that rely on the protection of this breakwater. Improvements to the breakwater should consider the South Shore Beach Relocation Study and any related plans. The height of the breakwater will be raised to provide better protection from waves overtopping the breakwater.

The crest elevation of the breakwater will be increased by ~7 feet (from +8 ft currently to +15 ft). The breakwater does not extend to the shore. It’s being constructed in place, atop the original breakwater. Based on the coastal design engineering evaluation, the additional 7 ft of height to the constructed breakwater is the minimum height needed for long-term wave protection of shoreline assets. A wider breakwater design was also evaluated, though that design also required increasing the height to prevent overtopping waves and was cost-prohibitive.

Picture of armor stone used for the 2023 breakwater spot repair.

Planning and design were completed for the reconstruction of the north section of the breakwater that provides protection to Cupertino Park, the South Shore Yacht Club, South Shore Park, and the Oak Leaf Trail. An appropriation was included in the 2023 Capital Improvements Budget for spot repair of the north section of the breakwater as the minimum needed to protect the shoreline from additional damage. The scope of work included the repair of 7 breaches/holes along the north section of the breakwater. This spot repair work was completed in Fall 2023.

Funding was allocated in 2024 to reconstruct a large portion of the north section of the breakwater fronting the South Shore Yacht Club. The scope of work includes construction to regrade the existing structure to provide a suitable base for rehabilitation/upgrade works, including salvage and reuse of suitable materials excavated from the existing structure; and placement of new filter and armor stone materials, sized to withstand design wave and ice conditions, with the crest elevation and width as required to provide the required level of wave protection to existing and proposed infrastructure located behind the structure. Great Lakes Dock & Materials completed construction activities at the breakwater from August through December 2024. They’ve completed most of the work; however, they were unable to finish before the end of December. The winter weather is posing challenging conditions and a safety hazard, the contractor is pausing work for the winter. Great Lakes Dock & Materials plans to re-mobilize the project site as soon as weather allows in Spring 2025. They’ll complete the remainder of the project at that time.

Crane used for placement of armor stone during 2023 breakwater spot repair work.