USACE to repair Hyannis Harbor breakwater

The U.S. Army Corps of Engineers, New England District has presented a proposal regarding the repair of the breakwater feature of the Federal Navigation Project (FNP) at Hyannis Harbor, Massachusetts.

The purpose of the proposed project is to restore full functionality of the FNP breakwater to meet its authorized purpose and to extend the repairs made in the 1960s to enhance the durability of the structure using modern construction methods and practices.

The most recent maintenance of the Hyannis Harbor FNP breakwater was performed in the 1960s when approximately 800 feet of the originally constructed, parapet stone breakwater was adaptively reconstructed.

This was accomplished by repurposing some of the original parapet stones and by adding new armor-stone to form a rubble mound configuration.

The last 400 feet of the outer end of the FNP breakwater was not repaired and remains vertically stacked, parapet stones dating back to the original construction in the 1890s.

Since the 1960s maintenance, coastal storms and a vessel collision in 2017 have caused damage to the structure resulting in an unbalanced settlement of parapet stones that remain from the original construction, and the displacement of armor stone along sections of the 1960s repair area.

These damaged areas have resulted in decreased functionality of the authorized structure and in an overall loss of protection of the 15.5-foot-deep FNP anchorage area behind it.

The proposed work is anticipated to begin in the spring of 2021 and would take approximately five months to complete.

Photo: USACE