Experts have called for the 3.5km high-speed train construction in Nakhon Ratchasima to be scrapped, with the cost of the entire high-speed rail system to undergo review.
The section is too short and alternatively a rail link should be built all the way to Nong Khai to fit into the larger setting of China's trans-Asia "One Belt One Road" project, said Samart Ratchapolsitte, former Bangkok governor and transportation expert who attended the Thai Development Research Institute forum on Friday.
A Transport Ministry source said earlier that China has agreed to speed up the design of the 3.5km section at Klang Dong station in Pak Chong district, Nakhon Ratchasima, with the route linking the northeastern province to Bangkok.
The Chinese side is also expected to reach a conclusion soon on its construction budget, which will allow for bids to be made on the project's concession this month or next month. Construction can then begin in September, the source said.
At the forum on Friday, Peerapol Thawornsuphacharoen, a deputy permanent secretary for transport, said the State Railway of Thailand's (SRT) feasibility study of the 3.5-km rail construction was complete.
The Transport and Traffic Policy Plan Office went through the study to decide whether it will be submitted to the Transportation Ministry and later forwarded to the cabinet for approval.
It was part of the 252-km high-speed rail project linking Bangkok and Nakhon Ratchasima, with the project having been scaled down after the Thai government decided to invest in the project itself.
"Building this very short length of track still requires huge investment as mobilising equipment on the site comes with fixed costs," said Mr Samart.
"After all, you can't test run the high-speed train over such a short length; it requires a distance of over 100km to do that," Mr Samart said.
Sumate Ongkittikul, TDRI research director on transportation and logistics policy, said the economic value of the high-speed rail project should be measured by such factors as the amount of time it will take to reduce commuting times and how much it can minimise the environmental impact.
"The key factor is distance, and we need to calculate the cost-benefits of transportation in the normal system compared with other modes. The fare structure should also be considered," he said.
"The high-speed train could be a mode for those who can afford it. The private sector could take part in the investment and the amount of government subsidy could be minimised," said Mr Sumate.
Mr Sumate called for transparency in the feasibility study to give the public a clear idea about the investment format, especially as regards to the state-private joint partnership.
Agachai Sumalee, King Mongkut's Institute of Technology Ladkrabang's director of Smart Cities Research Center, said the high-speed train system could be integrated into a multi-mode transport system.
"Other countries have different stages of high-speed rail development. The UK is discussing whether to expand its system while France has not been so successful in expanding their intermediate links."