Pattaya City's sand-fill project is expected to begin in October and will take around two years, said mayor Itthiphol Kunplome.
To extend the three-km beachfront to the eventual 35-metre width, will take 36,000 cubic metres of sand at a cost of Bt430 million (S$16.5 million).
The first 15 metres of the new beach would involve a sandbag wall to serve as an embankment, while the remaining 20 metres would be of sand.
The new beachfront will stretch for 2.7-km and cover around 60 rai, stretching from North, Central to South Pattaya beaches, Itthiphol said.
Itthiphol, who has been the mayor for six years, initiated this beach-extension project in 2010, requesting help from government agencies and local business owners.
Apart from the Marine Department, Pattaya City has hired the Aquatic Resources Research Institute, under Chulalongkorn University, as a project adviser.
The chief of the area Marine Department office, Rewat Phoriang, said the project had passed the Environment Impact Assessment, and is undergoing a bidding process, with this year's budget already available after approval from the Marine Department.
The sand to be used would be closest to the kind on Pattaya beach, found at beaches in Chon Buri and neighbouring Rayong, Itthiphol said.
The first beach areas to undergo the project would be those most damaged or affected from erosion.
When completed, the beach extension project is expected to revamp the image of Pattaya as a resort town with clean beaches and white sand, making it more attractive and have the potential of attracting 10 million tourists, as projected in the ASEAN Economic Community in 2015, Itthiphol said.
The head of the Pattaya Business and Tourism Association, Sinchai Wattanasartsathorn, said the extended beach would be beneficial to the local tourism industry, especially for Westerners who liked sunbathing.
Vendors who will rent out beach seats and sell food at the beach also praised the project.