In March 2018, Winter Storm Riley caused considerable damage to coastal infrastructure along the South Shore, including the seawall along Bay Avenue in Marshfield. After taking advantage of the 30-day emergency permitting exemption window temporarily lifted by MassDEP to stabilize its seawalls until a permanent design could be implemented, the Town of Marshfield engaged Tighe & Bond to design and oversee construction of a permanent seawall repair to protect Green Harbor and homeowners along Bay Avenue.
Upon inspection of the 105LF portion of failed seawall, Tighe & Bond determined the damage was the result of storm surge wave overtopping, heavy wave beach scour, and loss of the soils under and behind the wall due to wave action.
Tighe & Bond designed a sheet pile foundation and anti-scour cut-off wall at the toe of the replacement seawall to enhance future coastal resiliency. Remnants of the existing wall foundation and the new sheet pile wall were encased in a reinforced concrete footing, and a new seawall profile with wave recurve was cast in place over the footing. The steel plates and additional armor stone that were placed during the emergency response were removed, and the revetment was removed and reset along the length of the permanent repair to further protect the toe of the new wall. Work
was completed in 2020.