The Public-Private Partnership (PPP) Committee of Thailand, chaired by the Deputy Prime Minister, has approved the development of the Nakhon Pathom-Cha-am motorway through a PPP model. The total estimated investment of the project is THB79.01 billion (US$2.4 billion).

The 120km motorway will be located in the south of the country and is intended to ease congestion on the existing Highway No. 4. Its development was proposed and will be managed by the Department of Highways.

Under the proposed PPP model, the state would pay for land rights and invest around THB55.8 billion (US$1.69 billion) for civil works, while a private partner would cover construction expenses, consultancy services, operation and maintenance, and rest area management for 30 years from the opening of the motorway.