The boardwalk, costing €400,000, was opened in 2012 and runs the length of Claycastle beach. It has become a big attraction, drawing visitors to the beach every week, throughout the year.
Youghal Town Clerk Helen Mulcahy described the damage as “depressing”.
She said an engineer would assess the damage on Monday morning and “costing and repairs will start without delay”.
She asks that visitors refrain from walking the boardwalk until repairs have been conducted.
Ms Mulcahy added that the damage would be instructive in regard to the Phase II of the boardwalk project that will see it extended a further 1,500m to Redbarn.
The anticipated extension will form part of the National Coastal Walking Routes and is deemed essential to Youghal’s status as a burgeoning family tourism destination.