A large number of migrant birds, mostly lesser whistling ducks, will spend the winter at the wetland, which has rich biodiversity and a healthy ecosystem.
Songjit Sripeth, assistant district officer of Phu Kamyao District, said he presence of the colourful birds attracted bird watchers and tourists, which in turn helped boost the local economy.
Songjit said that local authorities planned to boost eco-tourism by promoting Rongtieu reservoir as its newest tourist attraction.
He said visitors could not only watch many migrant and native birds, they could stay overnight for free. Visitors are allowed to bring their own tent and camping equipment to the reservoir.
There is also trail for people to jog or ride bicycles around the reservoir, he said.