The Ministry of Transport, through the Department of Highways, is expediting the construction of the Nakhon Pathom-Cha-Am motorway, known as Motorway No. 8 (M8), with the aim of easing traffic congestion and improving connectivity to the southern region.
The project, which spans 109 kilometres, is designed to alleviate pressure on major roads such as Rama II Road and Phetkasem Road, key routes towards Bangkok.
The motorway will link Nakhon Pathom with Tha Yang in Phetchaburi and is expected to be completed by 2031. The four-lane motorway is anticipated to significantly reduce travel time between Hua Hin, Cha Am, Phetchaburi, Nakhon Pathom, and Bangkok. It will also integrate with the Bang Yai-Kanchanaburi motorway (M81) at the Nakhon Chai Si Interchange in Nakhon Pathom.
The Department of Highways has proposed a budget of 44 billion baht for the first phase of the project, which will cover the Nakhon Pathom-Pak Tho section (61 kilometres). The budget includes approximately 29 billion baht for civil engineering works, 3 billion baht for system operations and maintenance, and 12 billion baht for land expropriation. An estimated 38 billion baht will be sourced from loans.
Phase 1 of the motorway is expected to be submitted for Cabinet approval by the end of this year or in 2025. If approved, land acquisition and expropriation will begin in 2026, with construction likely to commence in 2027. The construction period is expected to take between three and four years, with the first phase becoming operational by 2031.
However, the second phase, which covers the Pak Tho-Cha-Am section (48 kilometres), has encountered opposition from local residents, particularly in sugar palm plantation areas, where concerns over land expropriation have persisted for four years. Residents have urged the department to consider alternative routes, including along Phetkasem Road.
In response to the concerns, the Department of Highways has re-examined the route for Phase 2. The finalised route is expected to support stable travel in the region, providing an alternative in the event of road closures on Phetkasem Road, particularly during floods. Once public consultations are completed, the detailed design process for Phase 2 will follow. The department expects this phase to proceed swiftly as it anticipates few obstacles in the remaining areas of land acquisition.
The motorway project is being implemented as a public-private partnership, with the state financing civil engineering works and private firms responsible for system installation and maintenance. The private sector will operate the motorway under a 32-year concession contract.
Once complete, the motorway will feature nine toll booths, located at key points along the route: Nakhon Chai Si, Talat Jinda, Bang Phae, Ratchaburi, Wat Phleng, Pak Tho 1, Pak Tho 2, Khao Yoi, and Tha Yang.
This project is part of Thailand’s efforts to improve road infrastructure, enhance regional connectivity, and reduce travel times, particularly for those travelling between Bangkok and destinations such as Hua Hin and Cha Am.
