West Sussex County Council (WSCC) will shortly make a temporary Traffic Regulation Order that will close the Riverbank footpath in Shoreham Beach.
This means from January 15, the path from its junction with the A259 to its junction with Riverside will be shut for at least six months.
The closure is needed to maintain safety while the Environment Agency carry out construction work on the Adur Tidal Walls flood defence scheme.
WSCC say that while the order is in effect, access to all properties (including houseboats) will be maintained at all times. An alternative route will be indicated on site.