The project was begun in 2020, and the first phase of 3.5km was completed on December 29, 2021.
The department is working on the second phase of 2.6km of beach.
"The width of the beach is expected to increase to an average of 50 metres once the project is completed," the Marine Department said.
The department expects the number of Thai and foreign visitors coming to Pattaya to increase as the Covid-19 crisis has eased.
Jomtien Beach is a town on the east coast of the Gulf of Thailand about 165km southeast of Bangkok in Chonburi province. It is about 3km south of Pattaya and is home to high-rise condominiums, beach side hotels, beaches, and restaurants.
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