A leader of the Seub Nakhasathien Foundation conservation group has vowed to launch a protest if a proposal to approve the Mae Wong dam in Nakhon Sawan goes before cabinet.
Sasin Chalermlarp's comment came as Agriculture and Cooperatives Minister Chatchai Sarikulya is reportedly seeking to use an order under Section 44 of the interim charter to press ahead with the much-criticised dam project.
Mr Sasin said he believed the minister was likely to have inadequate information on the scheme, focusing only on positive angles of the project.
He said he preferred not to say too much at this stage, but if this issue is proposed to the cabinet for consideration, a protest would be launched.
Mr Sasin said the foundation's alliances have presented potential negative impacts of the dam to the government and called for the project to be scrapped.
In 2013, Mr Sasin led a group of people to protest against the dam project in a 388km walk campaign, which successfully brought the project to a halt.
Meanwhile, a network of resource conservation groups also has slammed the minister's plan to ask for a Section 44 go-ahead, saying the dam would not improve water management.
Hannarong Yaowalers, chairman of Thai-Water Partnerships and adviser to the People Networks on the North River Basins, belongs to one of the groups in the network. He said he was disappointed with Gen Chatchai's plan to use the sweeping powers under Section 44 to kickstart the controversial project.
Mr Hannarong said the project could not proceed as a Ministry of Natural Resources and Environment committee looking into the project came to the conclusion that the loss of natural resources was not worth the gain in better water management.
"The ministry should stop trying to push a project that is already over. It could instead help people get access to more water by constructing small water reservoirs in villages," he said.
The network recently opposed Gen Chatchai's idea, saying the project is contrary to the government's policy on protecting and preserving forest zones.
The dam would also be at odds with all the conservation work done by Seub Nakhasathien, the conservationist after whom the foundation is named. He gave his life to protect the western forest complex.