Denbighshire County Council commissioned contractor and environmental specialists JBA Consulting to draw up plans.
The £18m scheme will involve installing rock armour and raising the height of the 400m long sea wall along the promenade between Splash Point and the slipway adjacent to Rhyl Golf Club.
Construction is expected to take 18 months and start next September, subject to planning permission, other necessary consents being granted and funding agreement.
Cllr Brian Jones, Denbighshire County Council’s lead member for Highways, Planning and Sustainable Travel, said: “Due to the low-lying nature of East Rhyl, wave overtopping remains the most serious coastal flood risk.
“Short-term resilience measures were undertaken by Denbighshire County Council following the 2013 storms and this project will provide substantial and durable protection in the long term.”